EPA 550/9-77-203
NOISE EMISSION STANDARDS
FOR TRANSPORTATION VEHICLES
PROPOSED MOTORCYCLE
NOISE EMISSION REGULATIONS
BACKGROUND DOCUMENT
November 1977
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF NOISE ABATEMENT AND CONTROL
WASHINGTON, D.C. 20460
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON DC 20460
ADDENDCM
PROPOSED MOTORCYCLE NOISE EMISSION REGULATIONS
BACKGROUND DOCUMENT APPENDIX
November, 1977
EPA 556/9-77-203
The Motorcycle Noise Emission Regulations Background Document
Appendix (published in a separate volume) contains an appendix which
is not included in the Table of Contents (page iv): Appendix J—
Exploration of a Stationary Test Incorporating an Electronic Ignition
Disable System.
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EPA 550/9-77-203
UNITED STATES
ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF NOISE ABATEMENT AND CONTROL
BACKGROUND DOCUMENT
FOR
PROPOSED MOTORCYCLE NOISE EMISSION REGULATIONS
November 1977
This document has been approved for general
availability. It does not constitute a standard, specification,
or regulation.
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FOREWORD
This background document was prepared in support of the
U.S. Environmental Protection Agency's Proposed Noise
Emission Regulations for New Motorcycles and New
Motorcycle Replacement Exhaust Systems. These Regula-
tions have been proposed pursuant to the mandate of Congress
as expressed in The Noise Control Act of 1972 (86 Stat. 1234).
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Table of Contents
Section 1
Section 2
Section 3
Section 4
Section 5
INTRODUCTION
INDUSTRY DESCRIPTION
2.1 Product Definition
2.2 New Vehicle Manufacturers
2.2.1 Market Shares and Sales
2.2.2 Product Lines
2.2.3 Motorcycle Prices
2.2.4 Typical New Motorcycle
Manufacturers
2.3 Aftermarket Industry
2.4 Motorcycle Dealers
2.5 Total U.S. Motorcycle Industry
Employment
2.6 Motorcycle Warranties
SOUND LEVEL TEST PROCEDURES
3.1 Application and Criteria
3.2 Candidate Moving Vehicle Test Procedures
3.3 Candidate Stationary Vehicle Test
Procedures
3.4 Measurement Distance Substitution
SOUND LEVEL DATA BASE
4.1 Content and Format of the Data Base
4.2 Test Site, Rider, and Vehicle Variables
4.3 Data Base Statistical Summaries
4.4 Aftermarket Exhaust Systems
4.5 Sound Levels at the Operator and
Passenger's Ear Position
PUBLIC HEALTH AND WELFARE ANALYSIS
5.1 Current Street Motorcycle Sound
Levels
Page
Number
1-1
2-1
2-1
2-3
2-8
2-13
2-13
2-13
2-34
2-46
2-51
2-52
3-1
3-1
3-2
3-26
3-36
4-1
4-1
4-14
4-18
4-20
4-28
5-1
5-3
5.2 Effect of Noise Regulations on Motorcycle
Sound Levels 5-8
5.3 Description of Traffic Noise Impact 5-10
5.3.1 Method for Calculating Traffic
Noise Impact " 5-14
5.3.2 Reduction in Traffic Noise
Impact 5-26
5.4 Motorcycles as an Individual Noise
Source 5-31
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Table of Contents (Continued)
Section 6
Section 7
5.5 Reduction of Single-Event Noise Impact
5.5.1 Speech Interference
5.5.2 Sleep Disturbance
5.5.3 Other Factors in Reduction of
Single-Event Noise Impact
5.5.4 Summary
5.6 Analysis of Noise Impact of Motorcycles
Used Off-Road
5.6.1
5.7
Distribution of Off-Road
Motorcycle Sound Levels
Detectability Criterion
Off-Road Motorcycle Operations
Estimate of Current Noise Impact
Relative Reduction in Noise
Impact
Operator and Passenger Noise Impact
5.6.2
5.6.3
5.6.4
5.6,
References
SOUND REDUCTION TECHNOLOGY
6.1 Diagnostic Evaluation of Sound Sources
6.2 Sound Reduction Technology
6.3 Impacts of Sound Reduction Technology
6.3.1 Performance Impacts
6.3.2 Operation Impacts
6.3.3 Maintenance Impacts
6.4 Production Variations
6.5 "Best Available Technology"
6.6 Lead Times
6.7 Deterioration of Motorcycle Sound
Levels
6.8 Relationship to Air Emission Control
6.9 Technology to Achieve Sound Levels
Based on Different Measurement
Methodologies
COSTS OF COMPLIANCE
7.1 Unit Cost Increases
7.1.1 Manufacturer Estimates for
Specific Models
7.1.2 Manufacturing Unit Cost:
Generalized Estimate
7.1.3 Research and Development Costs
7.1.4 Tooling and Other Manufacturing
Equipment Costs
Page
Number
5-32
5-35
5-54
5-58
5-59
5-64
5-65
5-69
5-70
5-70
5-74
5-78
5-83
6-1
6-1
6-3
6-11
6-11
6-13
6-13
6-14
6-16
6-18
6-19
6-21
6-21
7-1
7-1
7-1
7-4
7-25
7-30
11
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Table of Contents (Continued)
7.1.5 Testing and Certification Co_ts
7.1.6 Total Unit Cost Increases
7.2 Purchase Price Impacts
7.3 Replacement Exhaust System Price Impacts
7.4 Operation Costs
7.5 Maintenance Costs
7.6 Costs of EPA Air Emission Requirements
Section 8 ECONOMIC IMPACT ANALYSIS
8.1 New Motorcycle Sales Forecast
8.1.1 Historical New Motorcycle Sales
and Trends
8.1.2 Recent Market Developments
8.1.3 Baseline Forecast of New
Motorcycle Sales
8.2 Impacts on New Motorcycle Demand
8.2.1 Price Increase Impacts
8.3 Impacts on Demand for Products and
Service
8.3.1 Historical Aftermarket Sales
and Trends
8.4 Total Annualized Costs
8.4.1 Vehicle Annualized Costs
8.4.2 Aftermarket Exhaust Annualized
Costs
8.5 Expected Impacts on Individual
Manufacturers
8.5.1 Street Motorcycles
8.5.2 Off-Road Motorcycles
8.5.3 Aftermarket Exhaust Systems
8.6 Impact on U.S. Employment
8.7 Regional Impacts
8.8 Impact on GNP and Inflation
8.9 Impact on Foreign Trade
Section 9 OTHER ENVIRONMENTAL EFFECTS
Section 10 REGULATORY ALTERNATIVES
Page
Number
7-35
7-37
7-41
7-56
7-59
7-60
7-61
8-1
8-1
8-1
8-11
8-15
8-23
8-23
8-27
8-27
8-38
8-38
8-42
8-44
8-44
8-47
8-47
8-48
8-49
8-50
8-50
9-1
10-1
iii
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Table of Contents (Continued)
Page
Number
Section 11 ENFORCEMENT 11-1
11.1 General 11-1
11.2 Test Procedures 11-2
11.3 Original Equipment Sound Level 11-2
11.4 Universal Muffler 11-2
11.5 Production Verification 11-3
11.6 Selective Enforcement Auditing 11-5
11.7 Stationary Sound Level Verification 11-7
11.8 SEA: Stationary Sound Level 11-8
11.9 Labeling 11-8
11.10 Right of Entry and Record Keeping 11-9
11.11 Exemptions 11-10
11.12 In-Use Compliance 11-10
11.13 Acoustical Assurance Period (AAP)
Compliance 11-11
11.14 Administrative Orders 11-13
Appendix
A. MOTORCYCLE NOISE EMISSION TEST PROCEDURES A-l
B. TEST SITES AND INSTRUMENTATION B-l
C. PRODUCT IDENTIFICATION AND SOUND LEVELS C-l
D. STATE AND FOREIGN LAWS D-l
t
E. OPERATOR AND PASSENGER EXPOSURE TESTING
PROGRAM E-l
F. MOTORCYCLE DEMAND FORECASTING MODEL F-l
G. RELATION BETWEEN STANDARD TEST METHODOLOGIES
AND REPRESENTATIVE ACCELERATION CONDITIONS G-l
H. RECENTLY GATHERED MOTORCYCLE SOUND LEVEL DATA H-l
I. REFINEMENT OF MOTORCYCLE TESTING PROCEDURE 1-1
IV
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SECTION 1
INTRODUCTION
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Section 1
INTRODUCTION
Statutory Basis for Action
Through the Noise Control Act of 1972 (86 Stat. 1234), Congress
established a national policy "to promote an environment for all Americans
free from noise that jeopardizes their health and welfare." In pursuit of
that policy, Congress stated in Section 2 of the Act that "while primary
responsibility for control of noise rests with State and local governments,
Federal action is essential to deal with major noise sources in commerce,
the control of which requires national uniformity of treatment." As part
of that essential Federal action, subsection 5(b)(l) requires the
Administrator of the Environmental Protection Agency (EPA), after consul-
tation with appropriate Federal agencies, to publish a report or series
of reports identifying products (or classes of products) which in his
judgement are major sources of noise. Further, Section £ of the Act
requires the EPA to publish proposed regulations for each product identi-
fied as a major source of noise and for which, in his judgment, noise
standards are feasible. Such products fall into various categories, of
which transportation equipment (including recreational vehicles and
related equipment) is one.
Identification of Motorcycles as a Major Noise Source
Pursuant to the provisions of subsection 5(b)(1), the Administrator
on May 20, 1975Jpublished a report identifying new motorcycles as a major
source of noise. As required by Section 6, EPA is required to prescribe
standards for the noise emissions of new motorcycles which are requisite
to protect the public health and welfare, taking into account the magnitude
and conditions of use of new motorcycles, the degree of noise reduction
achievable through the application of best available technology, and the
cost of compliance.
In accordance with the authorities granted in Sections 3, 6, and
10 of the Act, EPA may establish performance standards for specific com-
ponents of those products which have been identified as major sources of
noise. Replacement exhaust systems, which are noise sensitive components
of motorcycles, have, in the judgment of the Administrator, been found
to warrant separate regulatory treatment as part of EPA's noise abatement
strategy for new motorcycles.
federal Register; 40FR 23105, May 28, 1975.
1-1
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Labeling
Provisions for requiring the labeling of products identified as
major sources of noise are contained in Sections 6 and 13 of the Noise
Control Act. Labeling of motorcycles will provide notice to buyers that
the product is sold in conformity with applicable regulations, and will
also make the buyer and user aware that the motorcycle possesses noise
attenuation devices which should not be removed or tampered with. Labeling
will also be of assistance to enforcement officials in determining compli-
ance with applicable laws and ordinances.
Preemption
After the effective date of a regulation for noise emissions from
a new product, Section 6 of the Noise Control Act requires that no State
or political subdivision thereof may adopt or enforce any law or regulation
which sets a limit on noise emissions from such new products, or components
of such new products, which is not identical to the standard prescribed
by the Federal regulation. Subsection 6(e)(2), however, provides that
nothing in Section 6 precludes or denies the right of any State or polit-
ical subdivision thereof to establish and enforce controls on environmental
noise through the licensing or the regulation or restriction of the use,
operation, or movement of any such product or con±>ination of products.
To assist in controlling motorcycle noise. State and local
authorities are encouraged to enact and enforce noise regulations for
motorcycles and replacement exhaust systems which complement Federal
regulations, as well as regulations controlling the use and operation of
motorcycles in areas where they are deemed to be necessary.
Study Approach
In June 1974 EPA published a preliminary study report which
examined motorcycle quieting technology and the costs of applying such
technology.2 This study provided the Agency with an initial assessment
of the feasability of motorcycle noise control, from which the Agency's
regulatory options could be further considered. Shortly after the major
noise source identification of motorcycles by the Administrator, EPA
initiated further research studies of quieting technology, cost and
economic impacts, and environmental impacts, to be used in assessing the
various Federal noise regulatory alternatives for this product.
Control of Motorcycle Noise, Volume I, Technology and Cost Information.
EPA publication 550/9-74-001A
1-2
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During the course of these studies, all major motorcycle
manufacturers, many smaller ones, and a number of manufacturers of
replacement exhaust systems were visited by representatives of the Agency
and its contractors. These visits were made for the purposes of collecting
technical data and information, and to allow the industry the opportunity
to become familiar with and participate in EPA's regulatory process.
Information and data collected from various.sources by EPA and
its contractors which were used by the Agency in assessing motorcycle
quieting technology, compliance costs, and health and welfare impacts are
presented in this document.
Public Participation
Throughout the development of this regulation an effort has been
made to allow all groups and organizations who have an interest in, or may
be directly affected by motorcycle noise standards, the opportunity to
participate in the rulemaking process. This public participation effort
has included meetings with concerned state, county, and city officials,
as well as with motorcycle user groups, industry associations, and motor-
cycle dealers. Advance copies of a draft Notice of Proposed Rulemaking
(NPRM) and selected sections of the supporting background document were
distributed to manufacturers and interested government officials several
months prior to publication of the NPRM to allow additional time for
analysis and comment. Appropriate officials in all 50 states were
contacted by telephone, and informational mailings were sent and follow-up
contacts made for the .purpose of obtaining viewpoints and opinions from
these officials. Ongoing attempts to coordinate Federal, state, and local
motorcycle noise control actions are being made by the Agency.
Outline and Summary of the Background Document
Section 1. Introduction
Section 2. Industry Description. General information on motor-
cycles, motorcycle manufacturers, exhaust system manufacturers, and the
structure of the industry is given in this section.
Section 3. Sound Level Test Procedures. This section contains a
discussion of existing noise measurement methodologies for motorcycles,
and a presentation of EPA's proposed procedure for use in regulatory
compliance testing.
Section 4. Sound Level Data Base. Sound levels of motorcycles
and replacement exhaust systems which were obtained using various test
procedures are presented in this section.
Section 5. Public Health and Welfare Analysis. An analysis of
current impacts of motorcycle noise, and impacts expected as a result of
various regulatory options is described in Section 5.
1-3
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Section 6. Sound Reduction Technology. A discussion of motorcycle
sound reduction feasability is contained in subsection 6.1. Subsection 6.2
presents an analysis of the various engineering techniques involved in
controlling noise from motorcycle noise subsources.
Section 7. Costs of Compliance. This section provides estimates
of the costs involved in applying these techniques to quiet motorcycles and
replacement exhaust systems to various not-to-exceed regulatory levels.
Section 8. Economic Impact Analysis. Estirates of the economic
impacts of various regulatory options on the manufacturing industry, on
specific firms, on employment and on other economic measures are contained
in this section.
Section 9. Environmental Effects. In this section the effects of
motorcycle noise regulations on air and water pollution, energy and natural
resource consumption, and land use patterns are considered.
Section 10. Alternatives to Federal Regulation. This section
contains a discussion of the various alternatives fcr controlling motor-
cycle noise other than a Federal new product standard.
Section 11. Enforcement. The various enforcement actions open to
EPA in ensuring compliance with Federal motorcycle noise regulations are
discussed in Section 11.
Appendix A. Motorcycle Sound Level Test Procedures. Texts of the
sound level test procedures discussed in Section 3 are presented in this
appendix.
Appendix B. Test Sites and Instrumentation. Descriptions and
photographs of the instrumentation and the test site locations used in
performing EPA's motorcycle noise testing are found in this appendix.
Appendix C. Product Identification and Sound Levels. In this
appendix are presented sound level data developed by EPA on individual
motorcycles and replacement exhaust systems.
Appendix D. A synopsis of State, local and foreign laws applicable
to motorcycle noise are contained in this appendix.
Appendix E. EPA's Operator and Passenger Exposure Testing Program
is described in this appendix.
Appendix F. Motorcycle Demand Forecasting Model. This appendix
describes the econmetric model used to forcast motorcycle demand.
1-4
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Appendix G. Relation Between Standard Test Methodologies and
and Representative Acceleration Conditions. The assessed relationship
between motorcycle sound levels under rapid acceleration conditions (the
proposed test procedure) and sound levels under representative uncon-
strained traffic acceleration conditions is detailed in this appendix.
Appendix H. Recent Motorcycle Sound Level Data. This appendix
contains data developed in a test program conducted by EPA to gain
additional data relating to the proposed test procedure and to investi-
gate tachometer response characteristics. Operator ear and stationary
test data are also presented.
Appendix I. Refinement of Motorcycle Testing Procedure. The
testing procedure which was published in draft form for coranent was
refined prior to the publication of the proposal on the basis of the
data described in Appendix H, and on manufacturer-supplied information.
The analyses behind these refinements are described in this appendix.
1-5
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SECTION 2
INDUSTRY DESCRIPTION
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Section 2
INDUSTRY DESCRIPTION
2.1 Product^ Definition
For the purposes of the EPA motorcycle noise regulation all
motorcycles which are designed and marketed for on-road operation are
considered to be "street" motorcycles, subject to noise standards for
street motorcycles. This category includes:
Street and highway motorcycles
Ch-road/of f-road combination motorcycles
Enduro motorcycles intended for limited street operation
Minicycles intended for street operation
ffotor-driven cycles
This street motorcyle category encompasses vehicles having the
following characteristics:.
(1) Approximately 50 to 1200c.c. engines, developing from 1 to 100
horsepower
(2) Two-stroke, four-stroke and rotary engines
(3) Che to six cylinders
(4) Liquid, fan and air cooling sytems
(5) TVio and three wheels
(6) Light to heavy weight
(7) Shaft and chain drive
(8) Manual and hydraulic torque converter automatic transmission
2-1
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for the purposes of the EPA noise regulation all motorcycles which
are designed and marketed for off-road and off-road competition use, with
the exception of motorcycles designed and marketed solely for use in
closed-course competition events, are considered to be "off-road" motor-
cycles. This off-road motorcycle category includes:
o Off-road, trail, and cross-country motorcycles
o Ehduro motorcycles not intended for street operation
o Minicycles not intended for street operation
o Trials motorcycles
o All-terrain motorcycles not intended for street operation
This off-road category encompasses vehicles having the following
characteristics:
(1) 50 to SOOc.c. engines
(2) Two-stroke and four-stroke engines (great majority two-stroke)
(3) Single cylinder
(4) Air cooled
(5) Two and three wheels
(6) Light weight
(7) Chain drive
(8) Manual, centrifugal clutch and continuously variable (belt)
automatic transmission
Ebr the purposes of the EPA noise regulation all motorcycles
designed and marketed solely for use in closed-course competition events
are considered competition motorcycles and are not subject to EPA noise
control standards. They are, however, subject to labeling provisions of
the motorcycle noise regulation. This competition category includes:
Competition motocross motorcycles
toad Racing motorcycles
Cval and dirt track motorcycles
2-2
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Two and three wheeled tractors are not considered to be motorcycles
for the purpose of the EPA motorcycle noise regulation. Electric and
battery-powered motorcycles are not subject to the provisions of the regu-
lations.
Mopeds are two-wheeled motor vehicles intended for use on streets
and roads. These vehicles, which are popular in Europe and Asia and which
have been recently introduced into the U.S., have the following features:
(a) Not more than SOc.c. engines
(b) Not more than 2 horsepower
(c) Top speed less than 30 m.p.h.
(d) Pedal-assisted
These vehicles typically have low sound levels (see Section 4), and
experience in other markets indicates that likely U.S. purchasers of mopeds
would not be expected to modify their vehicles to any great extent. For
these reasons, EPA's motorcycle noise regulation does not extend its appli-
cability at this time to mopeds. Relevant information on mopeds is
included in Table 2-1.
2.2 New Vehicle Manufacturers
More than 30 different manufacturers from all over the world sell
full sized 2-wheel motorcycles in the U.S. The manufacturers described
in Cycle Magazine's 1976 Buyer's Guide are listed in Table 2-2.
A partial list of three-wheeled motorcycle manufacturers is provided
in Table 2-3.
Manufacturers of mini-bikes/minicycles are listed in Table 2-3.
These manufacturers were listed in Cycle Magazine's 1976 Buyer's Guide,
along with the full-sized motorcycle manufacturers.
Almost all foreign motorcycle manufacturers have companies in the
U.S. distributing their products. The four major Japanese companies have
wholly owned subsidiaries located in Southern California. Most of the
smaller manufacturers are represented by independent distributing firms
who represent their brand under contractual arrangements.
2-3
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Table 2-1 MOPEDS
Introduced into the U.S. in 1975
1975 sales: 25,000
1976 sales: 75,000 (MBA estimate)
Features:
(A) 1-2 hp
(B) 50c.c. 2-stroke single cylinder engine
(C) Top speed less than 30 m.p.h.
(D) Pedal assisted for acceleration from complete stop
(E) Automatic transmission (centrifugal clutch or direct drive)
(F) Bicycle-type frame, brakes
(G) 60-100 pounds, 120-200 m.p.g., $300-$500
Sound levels:
65-75 dB(A) at 50 feet (full throttle/top speed)
73 dB(A) ISO procedure
Manufacturers:
Approximately 15 currently importing to U.S.—mostly bicycle
manufacturers
Marketing:
85% sold through bicycle dealerships
Annual Mileage:
Europe: 2500-3000 miles annually
U.S.: Insufficient experience
State Regulations:
Twenty-two states separately define mopeds as a separate vehicle;
remainder classify as motorcycle
Federal Regulation:
NHTSA: same as motorcycle except for brakes, lighting and turn
signal requirements
Source: Motorized Bicycle Association
2-4
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T^ble 2-2
MANUFACTURERS OF FULL SIZED 2-WHEEL MOTORCYCLES (Partial List)
BRAND/MANUFACTURER
COUNTRY
Benelli/Moto Benelli
BMW
Bultaco
Can-Am/Bombard ier
Carabela
Cheetah
DKW/Hercules
Ducati
Greeves
Barley-Davidson
Hodaka/Pabatco
Honda
Husqvarna
Indian
Jawa/CZ
KTM/Penton
Kawasaki
la Verda
MV Agusta
Maico
Montesa
Moto Qizzi
Moto Morini
MZ
NVT
Os sa
Bokon
Suzuki
Yamaha
Italy
West Germany
Spain
Canada
Mexico
U.S.
West Germany
Italy
United Kingdom
U.S./Italy
U.S.
Japan
Sweden
U.S./Taiwan
Czechoslovakia
Austria
Japan
Italy
Italy
West Germany
Spain
Italy
Italy
East Germany
United Kingdom
Spain
U.S.
Japan
Japan
Primary Source: Cycle Magazine, "1976 Buyer's Guide"
2-5
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Table 2-3
THREE WHEELED MOTORCYCLE MANUFACTURERS (Partial List)
BRAND
MANUFACTURER
Dunecycle
Explorer
He aid
Honda
Muskin
MTD
Pacesetter
Speedway
Tri-Sport
Allied Mechanical Products
Division of Tower Industries
Santa Fe Springs, California
Explorer International
Cwosso, Michigan
Heald, Inc.
Benton Harbor, Michigan
Honda Motor Company
Japan
HPE/Muskin Corporation
Subsidiary of Amcord, Inc.
Colton, California
MTD Products, Inc.
Cleveland/ Chio
Pacesetter Enterprises, Inc.
Cascade, Iowa
Speedway Products, Inc.
Mansfield, Chio
Promark
Norwald, Chio
BMB
Central State Tool and Die Company
2-6
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Table 2-3
MINIBIKES/MINICYCLES MANUFACTURERS (Partial List)
Arco Honda
Benelli Kawasaki
Carabela Montesa
Cestad Muskin
Pox Suzuki
He aid Yamaha
Source: Cycle Magazine "1976 Buyer's Guide".
Along with motorcycle manufacturers there are a few other U.S.
companies that are involved to some extent in the OEM (original equipment
manufacturer) segment of the market. These are companies which supply
major components such as exhaust systems and engines to the motorcycle
manufacturers. Representative companies in this category are:
Company Component Motorcycle
Nelson Industries Mufflers Barley-Davidson
Skyway Mufflers Hodaka
Briggs & Stratton Engines Beald
Tecumseh Engines Cheetah, He aid
Wisconsin Engines Heald
Most of these companies are not entirely dependent on the motor-
cycle industry. Their products are sold to manufacturers in other
industries such as automobiles, lawn mowers, snowmobiles, and so forth.
The remainder of the new motorcycle industry description is
oriented primarily toward the manufacturers of full sized, 2-wheel motor-
cycles, since this segment is by far the largest element in the industry
in terms of number of units sold.
2-7
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2.2.1 Market Shares and Sales
The new motorcycle manufacturing segment of the industry is
characterized by a snail number of manufacturers which have significant
sales in the U.S., and a large number of manufacturers with very limited
sales in the U.S. Available sales and market share data for each of the
companies are listed in Table 2-4. Ibtal industry sales figures since
1967 are shown in Figure 2-1.
The five leading manufacturers (Honda, Yamaha, Kawasaki, Suzuki and
AMF/Harley-Davidson) have 93 percent of the market, based on numbers of new
motorcycles registered. In is is an approximation because an estimated 30
percent of all motorcycles sold are not registered; however market share
inaccuracies are not likely to be great because all five sell the types
of models that are likely to be unregistered. Of the individual brands,
the largest share of the market is held by Honda, which has 40 percent of
the market, followed by Kawasaki - 17.2 percent, Yamaha - 16.2 percent,
Suzuki - 12.8 percent, Barley-Davidson - 6.9 percent, NTT Motorcycles
(Norton, Triumph) - 1.2 percent, and BMW - 1.0 percent.
All other manufacturers combined share approximately 5 percent of
the market, and none individually has a share of over 1 percent. Approxi-
mately 17 companies have less than 0.1 percent. These figures may be
slightly understated since many of the companies with limited -U.S. sales
specialize in off-road models which are generally not registered. Market
share trends for the five largest companies in the past few years are
shown in Figure 2-2. In 1975, Kawasaki, Suzuki, and Barley-Davidson
increased market shares, while Honda and Yamaha market shares declined.
The distribution of sales ranges has a similar dispersion. Honda's
annual retail sales in the U.S. are estimated to be over $500 million.
Sales for each of the four other leading manufacturers are estimated to be
between $100 million and $500 million. Two manufacturers have annual sales
estimated at between $10 to $50 million. All other companies are estimated
to have less than $10 million in annual retail sales in the U.S.
Market shares for product categories defined by engine displace-
ment size are shown in Table 2-5. Honda is the leader in all categories
except for the minibike/minicycle category. Barley-Davidson is ranked
second in the 750c.c. and above category with 24.6 percent of this market
segment, compared with Honda's 41.4 percent and Kawasaki's 18.8 percent.
2-8
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Table 2-4
MOTORCYCLE MANUFACTURER SALES AND MARKET SHAKE DATA: 1975
R
A
N
K
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Brand Manufacturer
Handa
Kawasaki
Yamaha
Suzuki
Barley-Davidson
Nbrton-Triumph
BMW
Bultaco
Husqvarna
Can-Am/Bombard ier
HDdaka
JAWA/CZ
Moto Guzzi
Benelli
Ducati
Location/Mfg .
Location(s)
Japan
Japan
Japan
Japan
U.S., Italy
U.K.
Germany
Spain
Sweden
Canada
U.S. /Japan
Czechoslovakia
Italy
Italy
Italy
Approx. Annual
-Retail Sales
Range ($M)*
500+
200-300
200-300
100-200
100-200
10-50
10-50
Less than 10
n
n
n
n
N
n
n
Percentage
of New Regis-
tration **
40.2%
17.2
16.2
12.8
6.9
1.1
1.0
0.5
0.5
0.4
0.3
0.3
0.3
0.1
0.1
Cum
Percentage
40.2%
57,4
73.6
86.4
93.3
94.4
95.4
95.9
96.4
96.8
97.1
97.4
97.7
97.8
97.9
* U.S. Motorcycle Sales Only (estimate).
** Based on 1975 data for number of new motorcycles registered (R. L. Folk
Registration Data).
2-9
-------
I/!
i/:
Q
I/I
d
1,250
1,000
750
500
250
SOURCE: MOTfORCYCU
INDUSTRY
COUNCIL
1967 1968
1969 1970 1971 1972
YEAR
1973 1974 1975
FIGURE 2-1. NEW MOTORCYCLE SALES, 1967-1975
2-10
-------
• £
c
LJ
o:
LU
605
50
40
30
20
10
0
71
HONDA
.KAWASAKI
•IIARLEY-UAVIDSON
•ALL OTHER
SOURCE: R.L.POLK REGISTRATION DATA
FIGURE
2-2. MAJOR MANUFACTURER'S MARKET SHARE OF REGISTERED MOTORCYCLES
2-11
-------
Table 2-5
MARKET SHARE BY HRODOCT CLASS*
R S
A I
N Z
K' E
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Minibikes/
Minicycles
Manufacturer
Yamaha
Kawasaki
Honda
Indian
Barley-Davidson
Chaparral
Cushman
Rockford
Rupp
Benelli
Steen
Premier
Pacesetter
Speedway
Other
Bet.
31.2
20.2
14.3
12.7
5.0
4.7
4.2
1.9
1.8
1.1
0.4
0.3
0.1
0.1
2.0
50-99c.c.
Manufacturer
Honda
Yamaha
Suzuki
Kawasaki
Barley-Davidson
Benelli
Bet.
58.9
19.0
8.1
8.0
5.5
0.5
100-1 69c.c.
Manufacturer
Honda
Yamaha
Kawasaki
Suzuki
Barley-Davidson
Bodaka
Can-Am
JAWA
Benelli
Bultaco
Husqvarna.
Pet.
34.3
21.5
20.8
18.2
2.3
2.2
0.6
0.1
0.05
0.05
0.05
*Market share as determined by R. L. Polk New Motorcycle Registration Data.
Non-registered motorcycles are not accounted for in this tabulation.
R S
A I
170-349c.c.
350-749C.C.
N Z
K E
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Manufacturer
Honda
Yamaha
Suzuki
Kawasaki
Barley-Davidson
Can-Am
Bultaco
JAWA
Husqvarna
Benelli
Pet.
31.7
23.5
22.2
14.2
4.9
1.7
1.1
0.3
0.3
0.1
Manufacturer
Honda
Yamaha
Kawasaki
Suzuki
Bultaco
BMW
JAWA
Husqvarna
Norton Triumph
Benelli
Pet.
45.8
20.8
19.3
12.6
0.8
0.4
0.1
0.1
0.1
•™
Manufacturer
Honda
Harley-Dav idson
Kawasaki
BMW
Suzuki
Norton
Moto Guzzi
Yamaha
Ducati
Pet.
41.4
24.6
18.8
4.1
4.1
2.8
2.6
1.1
0.5
*Market share as determined by R. L. Polk Naw Motorcycle Registration Data.
Non-registered motorcycles are not accounted for in this tabulation.
2-12
-------
2.2.2 Product Lines
There are major differences in the product lines offered by the
manufacturers. The four major Japanese manufacturers and Harely-Davidson
offer models in every category (see Table 2-6). Honda again is the leader
with 38 different models in all size and function categories. Barley-
Davidson has 13 models, but 7 are in the large (over 750c.c.)f street
model category. Most of the other manufacturers have model lines that
are limited to some extent. Many of the others specialize in either large
street motorcycles or small and medium sized dual-purpose or off-road motor-
cycles. More manufacturers sell small and medium dual-purpose and off-road
motorcycles than any other category.
Most models in the large street motorcycle category and almost all
tfcnda models have 4-stroke engines. Kawasaki and Yamaha have both 2-stroke
and 4-stroke models. The other manufacturers rely principally on 2-stroke
engines. Two manufacturers have models with rotary engines (Suzuki and
DKW). A list of engine types by manufacturer is provided in Table 2-7.
«
A list of the three most popular models for each of the major
Japanese motorcycle manufacturers is provided in Table 2-8.
2.2.3 Motorcycle Prices
In general, European motorcycles, particularly in the street
motorcycle, category, have higher retail level prices than those of major
Japanese or U.S. brands. Figure 2-3 shows a comparison of prices versus
engine displacement size for various street models listed in Peterson's
1975 Motorcycle Buyer's Guide. In the street category, European manufac-
turers generally offer a limited number of models at premium prices.
Comparisons of prices for off-road motorcycles are more difficult
to make because of the multitude of specialized functions off-road motor-
cycles have. HDwever, the Japanese brands are typically 10 to 20 percent
less in price for equivalent sized off-road models.
2.2.4 Typical New Motorcycle Manufacturers
Manufacturers of full sized motorcycles can be classified in the
following manner:
o Major Japanese Motorcycle Manufacturers
o Major U.S. Motorcycle Manufacturer - AMF/Harley-Davidson
o U.S. Motorcycle Manufacturers with Limited U.S. Sales
o Foreign Manufacturers with Limited U.S. Sales
2-13
-------
Table 2-6
MOTORCYCLE MANUFACTURERS PRODUCT LINE BY PRODUCT CATEGORY
Manufacturer
Under
lOOcc
Benelli/Moto Benelli
BMW
Bultaco
Can-Am/Bombard ier
Carabela
STREET-LEGAL
100- 170-
169cc 349cc
X
X X
350-
749cc
X
X
X
750cc
& Over
X
X
OFF-ROAD
Under 100-
lOOcc 169cc
X
X
X
170-
349CC
X
X
X
350-
749CC
X
X
X
Cheetah
Ducati
Greeves
Harley-Davidson
X X
X
X
,
X
X
Hercules
Hodaka/Pabatco
Honda X
Husqvarna
Indian
Jawa/Cz
KTM
Kawasaki X
LaVerda
MV Agusta
Maico
Montesa
Moto Guzzi
Moto Morini
X X
X X
X X
X
X
X
X
X
X
X
X
X
X
X X
X X
X
.
X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
MZ
NTV
Ossa
Penton
Rokon
Suzuki X
Yamaha X
X X
X X
X
X
X
X
X
X
X
X X
X X
X
X
X
X
X
X
X
X
Primary Source: Cycle Magazine, "1976 Buyer's Guide".
2-14
-------
Table 2-7
ENGINE TYPES BY MANUFACTURER
BRAND/MANUFACTURER
ENGINE TYPE(S)
Benelli/Moto Benelli
BMW
Bultaco
Can-Am/Borabard ier
Carabela
Cheetah
EKW/Hercules
Ducati
Greeves
Barley-Davidson
HDdaka/Pabatco
tonda
Husqvarna
Indian
CZ/Jawa
KTM
Kawasaki
LaVerda
MV Agusta
Maico
MDntesa
Moto Guzzi
MDto Morini
MZ
NVT
Cssa
Banton
Suzuki
Yamaha
4-stroke/2-stroke
4-stroke
2-stroke
2-stroke
2-stroke
4-stroke
2-stroke*
4-stroke
2-stroke
4-stroke/2-stroke
2-stroke
4-stroke/2-stroke
2-stroke
2-stroke
2-stroke
2-stroke
2-stroke/4-stroke
4-stroke
4-stroke
2-stroke
2-stroke
4-stroke
4-stroke
2-stroke
4-stroke
2-stroke
2-stroke
2-stroke
2-stroke/4-stroke*
2-stroke/4-stroke
*Exeluding one model with rotary engine.
2-15
-------
•Cable 2-8
MAJOR JAPANESE MANUFACTURER'S BEST SELLING
NEW MOTORCYCLE MODELS
Honda
1. Honda CB-750 (Street)
2. Honda CB-360 (Street)
3. Honda CB-550 (Street)
Kawasaki
1. Kawasaki KZ-400 (Street)
•
2. Kawasaki 900 Z-l (Street)
3. Kawasaki 350 (Street)
4. Kawasaki KS-125 (Enduro)
Yamaha
1. Yamaha XS-650 (Street)
2. Yamaha DT-125 (Enduro)
3. Yamaha DT-250 (Enduro)
Suzuki
1. Suzuki TS-250 Savage (Enduro)
2. Suzuki GT-550 Indy (Street)
3. Suzuki GT-380 Sebring (Street)
Source: Motorcycle Dealer News
2-16
-------
Of
I
:
O
V -
I—1 O
-J •-«
Ci
I.
'
'
4,000
3,500
3,000
2,500
2,000
1 ,500
1,000
YAMA
Y
HONDA CB :
IA RD250 O**
AMAHA
J60T^
\<*®
YAM;
XS 500
c
_^
\HA
LAVERl
SUZ
&
-------
A major motorcycle manufacturer is defined as having U.S. retail
level sales of motorcycles and parts of $10QM or over annually. Manufac-
turers with "limited11 sales have less than $100M in U.S. sales (measured at
the retail level) annually. Most in this category have less than $10M in
annual sales. The categories are defined in this manner because economic
impacts on typical firms in each category are likely to be significantly
different. Each category is described in more detail in the following
paragraphs.
Major Japanese Motorcycle Manufacturers
Major motorcycle manufacturers defined here are those Japanese
companies with over $100 million in annual U.S. retail sales. The four
companies (Honda, Kawasaki, Yamaha, Suzuki) are all very large industrial
concerns, of which motorcycles are a major or significant component of
total company operations. Data indicating the financial size and strength
of these companies are provided in Table 2-9.
There is some variation in the proportionate level of motorcycle-
related sales in each company. Handa is the world's largest motorcycle
manufacturer, and 40 to 50 percent of total corporate revenues come from
motorcycle sales. Kawasaki and AMF are essentially large conglomerates;
motorcycle-related sales for these two companies are an estimated 10 to 20
percent of total corporate revenues. Suzuki and Yamaha are smaller
companies, and have a much larger proportion (50 percent or more ) of their
total sales caning from the motorcycle business.
Approximately 20 to 40 percent of total Japanese motorcycle
production is exported to the U.S. Kawasaki's U.S. sales are propor-
tionately higher than this average, while Suzuki's are somewhat lower.
Characteristics of a major Japanese motorcycle manufacturer are
shown in Table 2-10. Ch the average, each Japanese firm produces one
million motorcycles annually, of which approximately 27 percent are
exported to the U.S. At the retail level, these motorcycles are worth
approximately $250M. ^reduction capacities of the companies range from
40,000 units per month and up.
2-18
-------
TABLE 2-9
MAJOR MOTORCYCLE MANUFACTURERS FINANCIAL DATA
COMPANY COUNTRY INDUSTRY
KAWASAKI HEAVY1'2 JAPAN SHIPBUILDING
INDUSTRIES INDUSTRIAL MACH
MOTORCYCLES
HONDA MOTOR3 JAPAN MOTORCYCLES
AUTOMOBILES
FARM MACH.
BMW1' GERMANY AUTOMOBILES
(BAYERISCHE MOTERN MOTORCYCLES
WERKE)
SUZUKI1 • ' JAPAN AUTOMOBILES
MOTORS MOTORCYCLES
YAMAHA MOTOR JAPAN MOTORCYCLES
REC. VEHICLES
AMF/HARLEY DAVIDSON U.S. MOTORCYCLES
LEISURE PRODS.
IND. PRODUCTS
SALES
($000)
1,980,137
1,791,098
9614,929
638,716
566,550
1,020,302
ASSETS
($000)
2,710,376
l,l»31,Hl6
619,881
1*69,1*86
312,273
807,703
NET
INCOME
($000)
37 J1*!
1*9,1*33
16,261
7,251*
10,953
22,126
STOCK-
HOLDERS
EQUITY
$000
289,082
336,131*
227,631
9l«,823
87,31*7
287,522
EMPLOYES
39,560
18,81*5
25,805
9,600
8,165
WORLD*
RANKING
197U 1973
95
109
205
29l*
80
101
ll*8
236
298
N.A.
SOURCE
1
1
1
1
2
3
1.
2.
3.
1*.
tt
•Xtt
Fiscal year ending March 31, 1975.
Includes pro-rated figures of subsidiaries that are more
than 50 percent owned.
Fiscal year ending August 30, 1971*.
Parent Company only.
Ranked by sales; excludes U.S. companies.
300 Yen per dollar conversion rate used.
Source:
1. Fortune Magazine, August 1975«
2. Diamond Report, Japan **
3. AMF Annual Report, 1971*.
-------
Table 2-10 CHARACTERISTICS CF TYPICAL MAJOR JAPANESE MOTORCYCLE MANUFACTURER*
U.S. RETAIL SALES RANGE
NO. OF FIRMS IN CATEGORY:
ADMINISTRATIVE LOCATION:
MANUFACTURING LOCATION:
PRODUCT LINE:
MOTORCYCLE PRODUCT LINE:
TOTAL CORPORATION SALES:
ASSETS:
NET INCOME:
NET PROFIT MARGIN:
STOCKHOLDERS EQUITY:
TOTAL MOTORCYCLE RELATED SALES****
DOLLARS
OMITS
MOTORCYCLE RELATED SALES, U.S.:
DOLLARS
UNITS
MARKET SHARE
NO. OF EMPLOYEES:
MAXIMUM PRODUCTION CAPACITY:
$100M+
4**
Japan
Japan***
Motorcycles, Automobiles,
Recreational Vehicles,
Industrial Machinery
Full line of models for
all product classes
$1,250M
$1,230M
$ 150M
2%
$ 201M
N.A.
1 M
$ 261M
0.27M
22%
8,000
40,000/Month and up
Source: Information from individual companies
N.A. - Not Available
*Based on 1974 data
**Honda, Kawasaki, Suzuki, Yamaha
***A11 manufacturing is done in Japan, Kawasaki has a facility in Lincoln,
Nebraska that assembles certain models
****Retail level sales
2-20
-------
Several features of Japanese financial practices and economic
conditions should be noted. In general, Japanese companies are highly
leveraged firms. The debt to equity ratios in the capital structure of a
typical Japanese company is much higher than in U.S. firms. This makes
Japanese companies more vulnerable in the event of downturns in business
activity—large interest expenses can create cash flow problems. However,
Japan has a central bank (Bank of Japan) that has very strong fiscal autho-
rity. The Bank of Japan can direct bank loans to companies with financial
problems, which alleviates the hazards associated with high leverage to a
great extent. However, if the condition is chronic, companies in Japan
declare bankruptcy just as they do in the U.S. In general, profit margins
of Japanese companies are lower than those of U.S. companies, but direct
comparison is somewhat meaningless due to the differences in capitalization,
as noted above. Because of the high degree of leverage, lower profit margins
can nevertheless net the same .return on owners investment as U.S. companies.
With regard to economic conditions, Japan has in the past few years
experienced relatively higher inflation rates than other countries in the
world, and this has diminished the competitive edge of Japanese companies
to some extent. In 1975, the divergence decreased somewhat.
A brief profile of the major motorcycle manufacturers is provided
in the following paragraphs.
Honda
The Honda Motor Company is located in Tokyo, Japan, and sells
automobiles, motorcycles, and miscellaneous non-vehicular products. The
company earned $49.4M in 1974 on sales of $1,791 million. Motorcycles
sales accounted for 46 percent of the total sales, automobiles accounted
for 35 percent of the total, and non-vehicular products sales made up the
remainder.
Honda is the world's largest motorcycle manufacturer and has the
largest share of the U.S. motorcycle market. In 1974, the company manu-
factured over 2 million motorcycles, an estimated 20 to 30 percent of
which were exported to the U.S. Honda has a diverse product line with 38
models offered, ranging from lOOOc.c road machines to 70c.c. mini-bikes.
Almost all Honda models have four-stroke engines, although a few of the
off-road models have two-stroke engines. The Honda Motor Company is
relatively strong financially due not only to its large share of the motor-
cycle market, but also to the strength of its other major product line
(automobiles).
The company has put a strong emphasis on R&D and has a separate
wholly-owned subsidiary, Honda R&D Company, Ltd., which conducts research
and development for both the automobile and motorcycle product lines. In
2-21
-------
recent years the company has put considerable emphasis on noise control
research, and the company is well positioned in this area. Because of its
size, financial strength, planning and research commitment and technical
facilities, Honda is likely to experience the least adverse impact of any
of the other companies in the industry. The only major disadvantage that
Honda has is the number of models it carries in its product line. Each
model, or possibly a smaller number of subset model categories, will
require individual effort and time for noise control research and
development.
Kawasaki
Kawasaki motorcycles are manufactured by Kawasaki's Engine and
Motorcycle Group, which provides 20 percent of the corporation's total
sales. This particular group is located in Akashi, Japan, and manufactures
motorcycles, gas turbine engines, chemical machinery and industrial robots.
The parent corporation, Kawasaki Heavy Industries, Ltd., is one of Japan's
biggest industrial concerns, with total sales approaching two billion
dollars.
Of the four major Japanese manufacturers, Kawasaki produces the
lowest total nunber of motorcycles, but exports the highest percentage of
its total production to the U.S. Kawasaki moved up to second in the U.S.
motorcycle market in 1975, largely due to the popularity of two models
introduced in 1974. These two models, 400c.c. and 900c.c. street cycles,
now account for a significant portion of Kawasaki sales, although the
company does offer a full range of street, combination and off-road bikes.
Twenty-nine different models ware manufactured for the U.S. market in 1975.
Kawasaki has a motorcycle assembly facility in Lincoln, Nebraska,
but most motorcycle assembly, and all engine assembly is done in Japan.
Approximately 200 employes are involved in the motorcycle manufacturing
operations.
The company has a technical research laboratory equipped with
sophisticated monitoring and diagnostic instruments. A noise research
effort has been in progress several years, and Kawasaki's capability in
this area (plant, equipment, personnel) seems well established.
Suzuki
Suzuki Motors is a leading manufacturer of motorcycles and light-
weight automobiles with 2-stroke engines. Company sales increased from
$467 million to $640 million between 1970 and 1974, an increase of 37
percent. Profits during this period declined some 34 percent, however,
from $10.9 million to 7.2 million.
2-22
-------
Suzuki exports approximately 30 models to the U.S., and sales are
fairly well balanced in all categories of motorcycles, although street and
dual purpose models account for the majority of sales. All of Suzuki's
models have 2-stroke engines, with the exception of one model with a rotary
motor and three 4-stroke street models which were introduced recently.
Yamaha
Yamaha Motor Company manufactures and sells motorcyles, motoped
bicycles, snowmobiles, recreational boats, engines and swimming pools. 3h
addition the company develops and operates recreational facilities. In
1955, the company separated from Nippon Gakki (a company that manufacturers
musical instruments), and is now an independent operation.
A large proportion of the company's revenue comes from motorcycle
sales. In 1974, the company manufactured slightly over one million motor-
cycles. Seventy-seven percent were exported, and approximately 20 to 30
percent were exported to the U.S.
Yamaha has extremely modern R&D facilities and equipment, and has
a demonstrated capability for noise control research and design.
Major U.S. Motorcycle Manufacturer - AMF/Harley-Davidson
AMF/Harley-Davison is the only remaining major U.S. motorcycle
manufacturer. The company was started in 1903, and has specialized in
manufacturing large touring motorcycles. 3h 1968, the company was acquired
by AMP, Inc., as part of AMF's extensive diversification effort. In 1975
AMF earned $32 million from sales of slightly over $1 billion. AMF products
are primarily oriented toward the leisure and industrial products market;
approximately 60 percent of sales and 50 percent of earnings come from
leisure products.
A breakdown of revenues by class of product in AMF's 1975 annual
report indicated that motorcycles and other travel vehicles provided $190.91
in revenues, or approximately 19 percent of AMF's sales. Motorcycles and
motorcycle parts sales account for most of this revenue, estimated to be
between $100 million and $200 million annually.
At the present time, the Barley-Davidson product line consists of
seven large touring models, all of which are lOOOc.c. or more, and six
smaller lightweight models of 250c.c. or less. A sidecar option is avail-
able for the larger models. A very large part of U.S. motorcycle sales
revenues comes from the larger models. In 1975, 74 percent of the
Harley-Davidsons registered in the U.S. were lOOOc.c. or larger.
2-23
-------
A total of 51,263 Barley-Davidsons were registered in 1975, and
nearly 38,000 of these were lOOOc.c. or larger. The larger models average
a retail price of $2800 or more; retail level sales for these models alone
were in the neighborhood of $100M. Barley-Davidson's sales on a unit basis
represented a 6.9 percent share of the market in 1975, based on registra-
tion data. Barley-Davidson's market share on a dollar basis is somewhat
higher, since its product line is oriented toward the larger, more expensive
motorcycles. Sales and financial characteristics of AMF/Barley-Davidson
are shown in Table 2-11.
It should be noted that Harley-Davison actually consists of two
relatively independent motorcycle manufacturing companies. The American
division manufactures the large (lOOOc.c. or over) touring models. The
wholly owned subsidiary in Varese, Italy designs and manufactures a line
of smaller models. Its operation is therefore similar to some smaller U.S.
companies which have manufacture motorcycles overseas. Since the opera-
tions are relatively, independent, each will be described separately.
Bar ley-Davidson, U.S.
It is a consensus opinion in the motorcycle industry that Barley-
Davidson has a unique niche in the market place. Buyers of the large
Barley-Davidson models demonstrate considerable loyalty to the brand, and
are relatively insensitive to design advancements and marketing campaigns
of competing models. It is the only U.S. motorcycle manufacturer which has
survived from the early 1900 *s to the present, resulting in the evolution
of a very strong consumer tradition. As evidence, Barley-Davidson has
increased its market share in spite of increased competition from major
Japanese manufacturers in the large street motorcycle category. In fact,
sales of the large models increased in 1974 and 1975, when sales of all
other companies declined considerably. Figure 2-4 shows comparative sales
trends, fart of the reason for Barley-Davidson's increase in sales in this
period is a general consumer shift toward* larger street motorcycles. Sales
of street motorcycles 900c.c. and larger increased 240 percent in 1974 and
65 percent in 1975 . Rrice data in Table 2-12 show this trend occuring
despite substantial increases in retail prices since 1973.
The strong brand loyalty that was indicated by industry sources to
be characteristic of Barley-Davidson buyers would seem to accord Barley-
Davidson certain advantages. It appears that Barley-Davidson sales are
considerably less sensitive to both price increases and declines in real
income than are other brands.
Motorcycle Industry Council, "Manufacturers Shipment Reporting System".
2-24
-------
Table 2-11
CHARACTERISTICS OF MAJOR U.S. MOTORCYCLE MANUFACTURING FIRM
(AMF/HARLEY-DAVIDSON)
CATEGORY:
LOCATION:
CORPORATE PRODUCT LINE:
MOTORCYCLE PRODUCT LINE:
TOTAL CORPORATION SALES:
NET INCOME:
NET PROFIT MARGIN:
ASSETS:
STOCKHOLDER'S EQUITY:
MOTORCYCLE AND TRAVEL
VEHICLE SALES:
MOTORCYCLE RELATES SALES, U.S.
DOLLARS:
UNITS REGISTERED (TOTAL)
1000C.C. AND OVER:
UNDER 1000C.C.:
C.C. NOT SPECIFIED:
MARKET SHARE:
NO. OF EMPLOYES, MOTORCYCLE
RELATED:
U.S. Motorcycle related sales over 100M
annually.
Milwaukee, Wisconsin
Leisure products (including motorcycles)
Industrial products and machinery.
o Milwaukee, Wisconsin and York,
Pennsylvania plants: large touring
motorcycles (l,000c.c. and l,200c.c.).
o Varese, Italy plant: small and inter-
mediate sized street, street/ trail
combination, and competition motorcycles.
$1,004,697,000
$ 32,133,000
3.2%
$' 779,470,000
$ 297,698,000
$ 190,794,000
(3)
$ 100,000,000+
(4)
51,263
37,987 (74%)
12,504 (24%)
774 (2%)
6.9%
3,300
Source: (Except otherwise indicated) AMF Annual Report, 1975.
(1) Based on 1975 data.
(2) Barley-Davidson AMF's largest manufacturing subsidiary.
(3) Motorcycle sales make up a very large percentage of motorcycle and
travel vehicle sales, but exact percentage not available
(4) R. L. Polk, New Motorcycle Registration Data, 1975. Motorcycles lOOOc.c.
and above made up 77% of total registration.
2-25
-------
BARLEY.DAVIDSON
- MODELS, lOOOcc
AND ABOVE
75
FIGURE 2-4. HARLEY-DAVIDSON NEW MOTORCYCLE REGISTRATION DATA
2-26
-------
AMF/BARLEY-DAVTD30N SUGGESTED RETAIL PRICES
1973 1974 1975
C.C. 3/15/72 10/27/73 2/18/74 7/15/74 8/11/74 2/25/75 4/21/75
125
175
250
1000
1200
$ 565
$2,182
$2,482
$ 635
$ 795
$2,338
$2,795
$ 660
$ 825
$2,440
$2,819
$ 749
$ 930
$1,130
$ 770
$ 930
$1,168
$2,735
<*0 •fAA _ _
9J , 411
$2,767
$3,330
Source: AMF/Barley-Davidson's Reply to Motorcycle Exhaust Emission ANPRM
Brand loyalty to Barley-Davidson motorcycles appears to arise from
several factors. Large Barley-Davidsons feature a longitudinal 45 V-Twin
engine with common crank pin; a unique design in today's motorcycle market.
This engine configuration provides Barley-Davidson motorcycles with low centers
of gravity, narrow profile, and powerful low-end torque. It also features
a low frequency asymetrical exhaust note that is unique and which has
customer appeal. In addition, the V-Twin engine provides specialized styling
for these motorcycles. The manufacturer believes that this unique "sound"
and appearance must be retained to preserve demand for Barley-Davidson
motorcycles.
Engines and parts for the large motorcycles are manufactured in
Barley-Davidson's Milwaukee, Wisconsin facilities, and are assembled in a
York, Pennsylvania plant. Approximately 3,300 people are directly employed
in the production of motorcycles, parts, and accessories. Barley-Davidson
indicates that another 25,000 people are indirectly affected to some extent
at supplier plants, distribution and sales locations, and Barley-Davidson
dealerships. Barley-Davidson is more vertically integrated than most other
manufacturers, in that it makes many of the parts and components which other
manufacturers normally buy from suppliers.
Typically, Barley-Davidson's primary manufacturing facilities and
equipment are older than most of its competitor's, in part because the basic
engine design and manufacturing processes have remained relatively stable
2-27
-------
over the years. In its 1974 annual report AMF indicated that Barley-Davidson
was having difficulty in meeting demand. Ebr this reason, AMF has been
spending considerable amounts for plant and equipment needed to raise pro-
duction capacity and modernize manufacturing processes. In its 1975 annual
report, AMF indicated that Barley-Davidson had doubled its engineering
staff, partly to meet new design requirements for exhaust and noise emission
controls.
From a cost standpoint, Barley-Davidson suffers a disadvantage in
view of the fact that Barley-Davidson's production base is 50,000 units
per year, as compared to the typical 270,000 units per year of its major
competitors. Period costs such as R&D and depreciation are thereby allo-
cated over lesser number of units. This disadvantage is tempered by the
fact that Barley-Davidson has a lesser number of models to manage, and that
its product line is composed of strictly large street motorcycles which
can sustain larger cost increases than smaller models on a relative basis.
Barley Davidson - Italy
This division produces the smaller lightweight models. The product
line is composed of small and intermediate sized (250c.c. or less) street
and combination (dual purpose) motorcycles. Approximately 12,500 of these
models were registered in 1975. The Varese operation falls more into the
category of a small U.S. or foreign manufacturer, and so the description of
a typical manufacturer with limited U.S. sales applies to this subsidiary.
Small Barley-Davidsons have recently been introduced to the non-0.S. market.
tfon-U.S. sales now account for a third to one half of Varese's production.
U.S. Motorcycle Manufacturers with Limited U.S. Sales
The U.S. motorcycle companies with limited shares of the U.S.
market include Chaparral, Cheetah, Fox, Be aid, Indian, Pacific Basin Trading
Company (PABATCO, distributor of Bodaka motorcycles) and Rokon. The extent
of manufacturing and assembly in the U.S. varies from company to company.
For example, Itokon buys various components from foreign manufacturers, but
60 to 90 percent of its motorcycles and mototractors (depending on which
model) are manufactured or assembled in the U.S. Pacific Basin Trading
Company (PABATCO) designs and markets Bodaka motorcycles in the U.S., but
the actual manufacturing is done in Nagoya, Japan by the Hodaka Industrial
Company. The Hodaka Company is essentially PABATCO's subcontractor. Indian
motorcycles are designed and marketed in the U.S. but the manufacturing is
done by Indian's wholly owned subsidiary, located in the Nantz Export
Processing Zone, Taiwan. Chaparral minicycles are designed and marketed
in the U.S., but manufactured in Taiwan (similar to the Indian operation).
Fox minicycles are primarily manufactured and assembled in the U.S., but
use components from other countries, such as Sachs motors from Germany.
2-28
-------
Table 2-13
CHARACTERISTICS OF TYPICAL SMALL U.S.
MOTORCYCLE MANUFACTURERS
RETAIL SALES RANGE:
NO OF FIRMS IN CATEGORY:
AIMINISTRATION LOCATION:
MANUFACTURING LOCATION:
PRODUCT LINE:
TOTAL MOTORCYCLE RELATED SALES**
DOLLARS:
WITS:
MARKET SHARE:
ASSETS:
NET PROFIT MARGIN:
NET WORTH:
NO. OF U.S. EMPLOYES,
MOTORCYCLE RELATED:
Less Than $10M
10 - 20 (Est.)
U.S. (Typically Great Lakes area)
Either U.S. or Foreign
Limited number of specialty models
$4.1M
11,000
Less Than 1.0%
$2M
Generally Negative
N/A
20
Source: Information from representative companies.
**Almost all companies in this category have all or very large part of
revenues coming from motorcycle business.
N/A - Not Available
2-29
-------
A typical U.S. company is relatively young and small (less than
$2-3 million in assets), manufactures 11,000 units and has annual sales in
the $4M range. Nat earnings in 1975 were negative or marginally in the
black because demand for new motorcycles was considerably down in 1975.
U.S. employment for the companies ranges from 2 to 34 employees. Employ-
ment of manufacturing subsidiaries or subcontractors is generally less
than 100. The small U.S. company's product line is generally limited to
minicycles, or small motorcycles (typically less than 185c.c.) that are
intended for off-road or dual purpose use. Characteristics of" a typical
U.S. company with limited sales is shown in Table 2-13. A brief descrip-
tion of some of these companies is contained in the following paragraphs.
Chaparral
Chaparral is a small company that manufactures 80c.c. and lOOc.c.
minicycles. The motorcycles are designed in the U.S., but are assembled
in Taiwan. The engines are manufactured in Japan.
Cheetah
Cheetah makes two trail recreation models that use 7hp and 5hp
Tecumseh engines. Production on the two models has been shut down due to
a shortage in parts. The motorcycles and engines are manufactured and
assembled in the U.S.
Fox
Ebx manufacturers 4 minicycle models. Two of the models use
133c.c. Tecumseh engines and the other two use German Sachs engines. With
the exception of the Sachs engines, most of the manufacturing and assembly
is done in the U.S. The company also manufactures motocross bicycles.
Heald
located in Benton Harbor, Michigan, Heald manufactures garden
tractors, roto-tillers and two and three wheel motorcycles in kit form.
Approximately 75 percent of sales are motorcycle-related. The motorcycles
ace recreational trail models which use Tecumseh, Briggs and Stratton,
Wisconsin and J.L.O. engines. Sales are primarily by mail order.
Indian
The Indian Motorcycle Company is a small U.S. firm that is
located in Southern California. Manufacturing is done by a wholly owned
subsidiary located in Taiwan. Seven models are manufactured - a lOOc.c.
street machine/ and 125c.c. and 175c.c. street, dual purpose and trail
models. All are 2-stroke. Approximately 50 percent of Indian's sales
2-30
-------
are in the U.S.; the remainder are exported. Indians are sold through
distributors and manufacturer's representatives. The company indicates
it is in a precarious position because of pending exhaust emission
control regulations which are more difficult to control on 2-stroke motor-
cycles.
Pacific Basin Trading Company (PABATCO)
PABATCO is located in Athena, Oregon and markets Hodaka motorcycles,
primarily small (250c.c. and less), 2-stroke motocross and off-road motor-
cycles. Bodakas are manufactured in Nagoya, Japan by the Hodaka Industrial
Company, which is essentially PABATCO's subcontractor. Over 90 percent of
Hodaka's business is through PABATCO.
Rokon
Rokon is located in Reene, Ifew Hampshire and manufactures
mototractors and motorcycles. The mototractors are 2-wheel drive vehicles
that are used for utility and agricultural work. The majority are exported.
The motorcycles are 2-stroke, 340c.c. off-road motorcycles with Sachs motors
and torque converter transmissions. Motorcycles represent approximately 40
percent of Rokon1 s business. Many of the components of RDkon motorcycles
cone from other countries, but the final assembly and check-out is done in
Itokon1 s New Hampshire facilities. Rokon manufactures approximately 500 to
1000 motorcycles per year.
At the present the following companies are no longer active in the
motorcycle market: Rupp; Rockford; Bandit; and Bird Engineering. Speed-
way has been acquired by Ebx.
Foreign Motorcycle Manufacturers with Limited U.S. Sales
There are approximately 25 foreign manufacturers with limited U.S.
motorcycle sales. A typical company manufactures 20,000 units, of which
4,000 are exported to the U.S. This quantity represents less than one-
half percent of the U.S. market, and is worth approximately $4M in sales
revenues. The product line is typically limited and concentrated in cer-
tain product categories. For example, many of the Italian companies such
as Ducati, La\ferda, Moto Benelli, Moto Guzzi, Moto Morini, and MV Agusta
market large street motorcycles. • BMW and NVT Motorcycles are two other
companies that specialize in large street motorcycles. Most of the other
companies specialize in small and intermediate sized (less than 350c.c.)
off-road and combination motorcycles. Characteristics of a typical foreign
motorcycle manufacturer with limited U.S. sales is shown in Table 2-14.
Capsule descriptions of some of the companies are contained in the following
paragraphs.
2-31
-------
T&ble 2-14
CHARACTERISTICS OF TYPICAL FOREIGN MOTORCYCLE MANUFACTURER
WITH LIMITED U.S. SALES
RETAIL SALES RANGE:
NUMBER OF FIRMS IN CATEGORY:
LOCATION:
PRODUCT LINE:
MOTORCYCLE PRODUCT LINE:
TOTAL CORPORATION SALES:
ASSETS:
NET PROFIT MARGIN:
NET WORTH:
TOTAL MOTORCYCLE REIATED SALES
DOLLARS:
ONUS:
MOTORCYCLE RELATED SALES, U.S.
DOLLARS:
UNITS:
MARKET SHARE:
NO. OF EMPLOYES
(U.S. DISTRIBUTOR):
less Than $1QM
25+
Europe, Taiwan, Mexico, Canada
Motorcycles, Bicycles, Mopeds
Limited number of specialty models
N/A
N/A
N/A
N/A
20,000
$4M (Est.)
4,000
less Than 1%
40
Source: Information from individual U.S. distributors of foreign
manufacturers.
N/A - Nob Available
2-32
-------
Benelli
Moto Benelli is an established Italian firm that is a subsidiary
of DeTbmaso Industries. Benelli markets 250c.c., SOOc.c., 650c.c. and
750c.c. street motorcycles.
BMW
BMW is an extremely large manufacturer located in West Germany.
Total corporation sales in 1974 approached $1 billion. Automobiles and
large touring motorcycles are major product lines. According to
registration data, BMW had a one percent share of the U.S. market in 1975,
and ranked seventh among all manufacturers. BMW sells large touring motor-
cycles with horizontally opposed twin cylinder engines and shaft drive.
like Honda, BMW can make use. of expertise and facilities developed for the
automobile market.
Can-Am
Can-Am motorcycles are manufactured by Bombardier, Ltd., a large
Canadian firm that also manufactures snowmobiles, industrial vehicles,
all terrain tractors, and winter sport accessories and apparel. Can-Am
specializes in high performance enduro and competition motocross motor-
cycles. Bombardier is presently making 10,000 motorcycles per year.
Hercules
Hercules are manufactured by DKW/Hercules, part of the Wankel-
Fichtel-Sachs Manufacturing Group, which is one of Germany's largest
manufacturers of motorcycles. The group is also a major supplier of
engines to other motorcycle manufacturers. DIW makes enduro and off-road
motorcycles primarily. DKW also markets a rotary engine model, although
production of this model is relatively limited.
Husqvarna
Rusqvarna is a large Swedish manufacturing company which produces
engines, chain saws, appliances, sewing machines, as well as motorcycles.
The company specializes in very high quality off-road cross country and
competition models. Approximately 75 percent of Husqvarna's total production
is exported to the U.S.
2-33
-------
KTM
RTM sells strictly off-road motorcycles in the U.S. Sales in the
Western U.S. were initiated in late 1975. The parent company is a medium
sized Austrian company which manufactures motorcycles and bicycles.
LaVerda
laVerda is an Italian motorcycle manufacturer that makes large
street motorcycles. Rrcduct line is primarily in the 750-1000c.c. size
range.
2.3 Aftermarket Industry
The structure of the aftermarket segment of the industry is
entirely different from the new motorcycle market segment. The aftermarket
industry is primarily domestic, as compared with the extreme international
characteristics of the new motorcycle segment of the industry. There are
an estimated 900 companies in the U.S. that are involved to some extent
with manufacturing and distributing motorcycle aftermarket products . The
majority of these firms are relatively small, young companies. Most have
motorcycle-related sales of less than $1 million per year and have been in
business less than five years . There is no single company or group of
companies that dominate the market.
General Aftermarket Company
Firms in the motorcycle aftermarket industry can be classified as
manufacturers only, manufacturers and distributors, and distributors only.
The approximate number of companies in each classification are:
Manufacturers Only 270
Manufacturer/Distributor 279
Distributors Oily 351
Source: Motorcycle Dealer News, "Industry Overview".
These companies are not all strictly motorcycle oriented; a
significant number are diversified and involved in other industries. For
example, some of the motorcycle aftermarket manufacturers are large automo-
tive aftermarket companies which have expanded into the motorcycle market.
Some firms also serve the snowmobile, boating, bicycle and other miscel-
laneous industries. In general, the smaller companies in the industry
have a large or complete dependence on motorcycle product sales, and the
.large companies have a relatively small dependence on motorcycle sales.
"Motorcycle Dealer News, "Industry Overview".
2-34
-------
Characteristics of typical aftermarket manufacturers are shown in
Table 2-15. Data on some general characteristics of the aftermarket
industry is present in Table 2-16.
A brief profile of manufacturers, manufacturer/distributirs and
distributors is provided below, and summarized in Figures 2-5 and 2-6.
Manufacturers Only
Ninety percent of manufacturers-only firms characterize their sales
as national in scope. The majority do much of their business through ware-
house/distributor direct or through manufacturing representatives. Cnly
32 percent of the companies derive more than 70 percent of their business
from the motorcycle industry. The majority (60 percent) have less than 20
1
percent of their sales caning from motorcycle products .
Manufacturers/Distributors
Seventy percent of the manufacturers/distributors derive more than
70 percent of their sales from motorcycle related business. In addition,
70 percent have less than $500,000 in annual motorcycle related sales.
The manufacturer/distributors sell directly to dealers and accessory shops
1
and to a lesser extent to other distributors .
Distributors
tore than 60 percent of the distributors derive more than 80
percent of their sales from motorcycle related sales. However, 66 percent
of the companies have motorcycle product sales of less than $500,000 per
year. Mast of the distributors are regional/local with only 16 percent of
the companies considered to be national distributors.
In essence, the aftermarket segment of the industry is in the
formative stage, with numerous small companies with specialized product
lines or functions competing with each other. In addition, these companies
are facing increased competition from the major motorcycle manufacturers who
recognize the growth aspects in this industry. It is likely that some of
the more marginal operations will fail, or be combined with other companies
in the next few years. The emerging nature of the industry mak^s it more
difficult to assess the likely impact of noise control programs on the
aftermarket industry structure.
1
Motorcycle Dealer News
2-35
-------
Tfeble 2-15
CHARACTERISTICS OF TYPICAL MOTORCYCLE
AFTERMARKET MANUFACTURED/DISTRIBUTOR
PRODUCT LINE:
CATEGORY:
NO. OF FIRMS IN CATEGORY:
SALES:
NO. OF EMPLOYES:
AGE:
CATEGORY:
NO. OF FIRMS IN CATEGORY:
SALES:
NO. OF EMPLOYES:
AGE:
CATEGORY:
NO. OF FIRMS IN CATEGORY:
SALES:
NO. OF EMPLOYES:
AGE:
Source: Motorcycle Dealer News
Replacement Parts, Accessories,
Apparel
Manufacturer Only
270
$250,000
24 (median)
4 years (median)
Manuf acturer/t>i str ibutor
279
$250,000
8 (median)
5 years (median)
Distributor Only
351
$250,000
5 (median)
4 years (median)
2-36
-------
MANUFACTURER
ONLY
MANUFACTURER/
DISTRIBUTOR
40%
30%
20% .
10%
0% .
40
26
11
1
7
6
40% or,
30%
20%
10%
0%
32
11
R
5
3
.3
DISTRIBUTOR
ONLY
30%
?0%
10%
0%
34
32
:;/:/•:•
13
m
9
2
4
Under 250K 500K 1M 2.5M 5.0M 7.5M Over
250K to ' to to to to to 10M
500K 1M 2.5H 5.0M 7.5M 10M
Source: Motorcycle Dealer News
FIGURE 2-5. AFTERMARKET FIRMS - ANNUAL REVENUES FRCM MOTORCYCLE BUSINESS
2-37
-------
4n?
MAfJUFACTURFR 30%
ONLY
20%
10%
0
60%
^n^
MANUFACTURER- 40%
DISTRIBUTOR
30%
20%
10%
0
40
16
WMO
20
2
I— i
5
PI
6
H
6
PI
6
6
Fl
I
b
^
13
20
54
DISTRIBUTOR 30%
ONLY
50%
40%
30%
20%
10%
0
10
R
n
&
o
II
r*i
r2!
A
10
52
••/.-/-
:^i
Under 10 20 30 40 50 co 70 80 90
102 TO TO TO TO TO TO TO TO TO
20 30 40 50 60 70 80 90 100
FIGURE 2-6. AFTERMARKET FIRMS - PERCENTAGE OF REVENUES
FRCM MOTORCYCLE BUSINESS
2-38
-------
Exhaust Systems/Components Manufacturers and Distributors
The segment of the aftermarket that will be most directly affected
by noise regulation are companies which manufacture and distribute
exhaust system products - mufflers, exhaust pipes, expansion chambers,
exhaust headers and so forth. There are over 160 companies in this group
who are selling in a market that is estimated to be slightly over $30
million per year. Most are located in California. Average sales for
manufacturing companies are estimated to be approximately $320,000. The
leader in the industry is believed to sell between $2 and $3 million worth
of exhaust system products per year. Exact distribution of sales in this
subsegment of the industry is unavailable but the general nature is evident.
The companies are relatively small and competing in a crowded market.
Based on a survey of 11 representative firms, a typical company in
the exhaust system segment of the aftermarket manufactures 30,000 exhaust
systems and components per year, has annual sales of $0.7 million, and nets
5 to 7 percent profit each year. Market shares range from 1 to 3 percent of
the total. Total assets are approximately $300,000, but 60 to 75 percent of
these assets are in inventory. Typical characteristics of exhaust system
manufacturers shown in Table 2-17 are derived from manufacturer proprietary
information.
Typically the president/owner of the company is also the designer
of the exhaust systems and components, although one or two people may
assist him in this function. Design emphasis is on styling, performance,
and noise control; the priorities are dependent upon individual company
philosophies. Noise control technical capabilities vary from company
to company, although most use fairly standard noise control techniques,
and the "cut and try" method for design advancements. Research facilities
are generally non-existent or very limited.
Characteristics of consumer buying patterns for replacement parts
and equipment, and projections of future market shares of replacement parts
manufacturers and presented in Table 2-18 through 2-21.
2-39
-------
•able 2-16
AFTERMARKET INDUSTRY CHARACTERISTICS
Total motorcycle aftermarket sales*
$1.8 billion
Number of U.S. afterraarket manufacturers
550 approximately
Exhaust system aftermarket sales
$30,663,000 retail
616,000 purchasers
862,000 units
$49.73 average per unit
Intake system aftermarket sales
$5,880,000 retail
840,000 purchasers
1,344,000 units
$7.00 average per unit
*Ziff-Davis Publishing Co., "Motorcycle Aftermarket Study" - 1974,
2-40
-------
Table 2-17
CHARACTERISTICS OF TYPICAL MOTORCYCLE AFTERMARKET
EXHAUST SYSTEM MANUFACTURER
CATEGORY:
NO. OF COMPANIES IN CATEGORY:
LOCATION:
PRODUCT LINE:
TOTAL COMPANY SALES:
ASSETS:
NET PROFIT MARGIN:
NET WORTH:
TOTAL MOTORCYCLE EXHAUST RELATED SALES
DOLLARS:
UNITS:
MARKET SHARE:
NUMBER OF EMPLOYES, MOTORCYCLE
RELATED:
Aftermarket Exhaust System
Manufacturer
90+
U.S., Predominately California
Mufflers, Expansion Chambers,
Headers
$0.7M*
$300K**
5-7%
N/A
$0.7M
30,000
1-3%
40
Source: Information from sample of representative companies.
*Most companies derive most or all of their business from exhaust system
sales.
**Generally 60 to 75 percent of assets is in inventories.
N/A - Not Available
2-41
-------
•Cable 2-18
TIME OF PURCHASE OF MOTORCYCLE ACCESSORIES
ENGINE PARTS/HIGH PERFORMANCE MARKET
MONTHS AFTER
MOTORCYCLE PURCHASE
AT SAME TIME
1-2 MONTHS
5-7 MONTHS
8-12 MONTHS
SPECIAL
SPROCKETS
21.0%
15.6
24.1
21.0
EXPANSION
CHAMBER
27.2%
9.5
12.2
12.6
EXHAUST
SYSTEM
36.0%
6.6
7.2
11.2
SILENCER SPARK
ARRESTERS
40.3%
11.7
6.4
6.3
NOTE: MOST OF THE NOTED ITEMS ARE PURCHASED WITHIN THE FIRST 2 YEARS AFTER
PURCHASE OF A NEW MOTORCYCLE
Source: 1975 Motorcycle Market Stiriy
Power-Robertson & Company
2-42
-------
l^ble 2-19
OWNERS CP MOTORCYCLE ACCESSORIES
ENGINE PARTS/HIGH PERFORMANCE MARKET
AFTERMARKET
ACCESSORY
SPECIAL SPROCKETS
EXPANS. CHAMBER
EXHAUST SYSTEM
SILENCER-SPARK
ARRESTOR
% *
TOTAL
OWNERS
11.8
4.5
10.9
4.9
%
HONDA
OWNERS
9.6
2.9
12.6
3.9
%
YAMAHA
OWNERS
19.7
11.2
8.3
8.7
%
SUZUKI
OWNERS
21.3
9.8
*
9.7
9.8
%
KAWASAKI
OWNERS
16.9
6.3
6.0
7.1
%
BARLEY
CWNERS
16.8
6.3
25.0
7.1
NOTE: *OWNERSHIP OF INDICATED ITEMS BY PERCENTAGE OF MOTORCYCLISTS1 QUESTIONED.
Source: 1975 Motorcycle Market Study
Power-Robertson & Company
2-43
-------
Table 2-20
MANUFACTURERS OF MOTORCYCLE ACCESSORY ITEMS
•
CURRENT/FUTURE MARKET ANALYSIS
EXHAUST SYSTEMS
MAJOR
BRANDS
HONDA
HOOKER
YAMAHA
SUZUKI
TORQUE
BASSANI
BUNSTALL
KAWASAKI
RUPP
ALL OTHERS
CURRENT SHARE
OF MARKET
PERCENT
21.0
13.0
5.0
4.0
4.0
3.0
2.0
1.5
.5
46.0
FUTURE SHARE
OF MARKET
PERCENT
11.0
30.0
9.0
7.5
1.5
41.0
Source: 1975 Motorcycle Market Study
Power-Robertson & Company
2-44
-------
Table 2-21
MANUFACTURERS OF MOTORCYCLE ACCESSORY ITEMS
CURRENT/FUTURE MARKET ANALYSIS
EXPANSION CHAMBERS
MAJOR
BRANDS
HOOKER
BASSANI
YAMAHA
SUZUKI
J & R
KAWASAKI
HONEA
ALL OTHERS
CURRENT SHARE
OF MARKET
PERCENT
22
20
8
4
3
2
2
39
FUTURE SHARE
OF MARKET
PERCENT
32
26
3.5
—
3.5
2.0
—
33
Source: 1975 Motorcycle Market Study
lower-Robertson & Company
2-45
-------
2.4 Motorcycle Dealers
The major retail outlets in the motorcycle industry are dealers,
motorcycle accessory shops, department store chains, discount stores, mail
order firms and others (e.g., service stations). Dealers sell new and used
motorcycles, and aftermarket products and services, while all the other
outlets deal in the aftermarket only. Aftermarket parts and accessory
retailing is done primarily by the dealers, who are responsible for 75 to
80 percent of total-sales (refer to Table 2-22).
Table 2-22
SALES OF MOTORCYCLES, PARTS AND ACCESSORIES
BY TYPE OF OUTLET
PERCENTAGE OF TOTAL
OUTLET
Franchised Dealerships
Mail Order
Accessory Shops
Department/Discount Stores
Other
RETAIL SALES
75
10
6
6
1
- 80
- 12
- 8
- 8
- 2
Source: Frost and Sullivan
. There are an estimated 7,000 to 8,000 independent franchised dealers
in the U.S. selling motorcycles and aftermarket products and services. Most
carry one brand of motorcycle exclusively, although a significant number
carry more than one brand. Multiple brand representation is generally only
for motorcycle manufacturers with a small specialized product line; the
typical multiple brand dealer represents more than one of these types of
brands to extend the range of models he can sell.
Slightly more than 50 percent of dealer sales are generated from
new motorcycle sales, while accessories, parts and services sales make up
almost 40 percent. The breakdown is as follows (reference Figure 2-7):
2-46
-------
New Motorcycle Sales 53%
Used Motorcycle Sales 10%
Accessories 14%
Parts 8%
Service 15%
100%
Average annual sales for motorcycle dealers is approximately
$360,000. The distribution of dealers by total retail sales volume for
1974 and 1975 is shown in Figure 2-8. Approximately 50 percent of the
dealers are in the $100,000 - $499,000 sales range. Dealers with sales
under $50,000 per year went from 16 percent in 1974 to 8 percent in 1975,
indicating that some of the marginal dealers folded as a result of the
decline in demand for new motorcycles in 1975. Characteristics of a
typical dealer are shown in Table 2-23.
The typical dealer has relatively small profit margin (3% before
taxes), and relies heavily on short term financing for his inventory, which
makes up a large proportion of his assets. When sales volume drops dealers
are often stuck with a large inventory, and interest expense becomes
critical. When this occurs, the dealers are forced to discount their prices,
thereby reducing their profit margin even more. This process is especially
damaging to the smaller dealers who are generally undercapitalized and have a
low sales volume to support their operations.
2-47
-------
Motorcycle Sales
Source: Motorcycle Dealer News
FIGURE 2-7.
MOTORCYCLE DEALERS TYPICAL DISTRIBUTION
OF RETAIL SALES, 1974
2-48
-------
60%
c r\ $/
1975
20%
105!
0
60%
50%
1 n*74 OA
-------
Table 2-23
CHARACTERISTICS OF TYPICAL FRANCHISED MOTORCYCLE DEALERSHIP*
CATEGORY:
NO. OF FIRMS IN CATEGORY:
LOCATION:
PRODUCT LINE:
ASSETS:
NET PROFIT MARGIN (AT):
NET WORTH:
TOTAL MOTORCYCLE HELMED SALES
DOLLARS:
WITS:
NO. OF EMPLOYES:
Franchisee! Dealership
7,000 - 8,000
U.S.
New Motorcycles, Used Motorcycles,
Parts, Accessories, and Services
N/A (Primarily Inventory)
3%
N/A
$360,OOOAear
190 New Motorcycles (median)
Equivalent of 5 Full Time
Source: Motorcycle Dealer News
Motorcycle Industry Council
*Based on 1974 Data
N/A - Not Available
2-50
-------
2.5 Total U.S. Motorcycle Industry Employment
Tbtal U.S. motorcycle industry employment is showi. below:
•Bible 2-24
ESTIMATED U.S. MOTORCYCLE INDUSTRY EMPLOYMENT
INDUSTRY SEQ4ENT NUMBER OF EMPLOYEES SOURCE
New Motorcycle Manufacturers
and Distributors
Aftermarket Manufacturers
and Distributors
Franchised Dealerships
Other Retail Outlets
Miscellaneous
TOTAL
5,600 1
12,000* 2
35,000 2,3
5,000 4
2,000
59,600
Data derived from following sources:
(1) Information from various companies.
(2) Motorcycle Dealer News.
(3) Motorcycle Industry Council.
(4) Energy and Environmental Analysis, Inc., "Economic Assessment
of Motorcycle Exhaust Emission Regulations".
* 1200 in aftermarket exhaust system manufacturing.
2-51
-------
2.6 Motorcycle Warranties
Street motorcycles are often warranted against defects in
materials and assembly for six months and a corresponding distance of
travel. Shorter warranties (three months) and longer ones (one year)
are also known. Off-road motorcycles are often warranted for three or
six months, although semi-competition models often have no warranty.
Rare competition motorcycles are almost never warranted. To EPA's
knowledge formal warranties are extended on very few replacement exhaust
systems, although many manufacturers will repair or replace obviously
faulty products.
2-52
-------
SECTION 3
SOUND LEVEL TEST PROCEDURES
-------
Section 3
SOUND LEVEL TEST PROCEDURES
3.1 Application and Criteria
Existing noise test methodologies which have been either adopted,
approved, or proposed in the United States or in other countries were
examined for possible use in the EPA regulation. Several criteria were
established to review these procedures and to provide a basis for possible
refinement.
Ideally, a sound measurement procedure for new motorcycles should:
(a) Characterize the sound as perceived at the wayside in terms that
relate to the impact of noise on humans.
(b) Characterize the sound during the most annoying mode(s) of opera-
tion commonly encountered in areas of impact.
(c) Measure sound levels on a comparable basis for all motorcycles in
specified categories, as measured in the operating mode(s) identified
above.
(d) To the extent possible, satisfy several practical requirements.
Specifically, a testing procedure should be:
(1) Clear and easily understandable.
(2) Repeatable with a minimum of variation.
(3) Capable of being conducted with a minimum of meteorological
and site-to-site variability.
(4) Insensitive to configuration options (such as gearing,
sprocket ratios) which can result in variations of measured noise
disproportionate to actual variations in vehicle noise.
(5) Free from ambiguous procedural situations requiring determi-
nations which can affect the measured sound level.
(6) Minimally influenced by factors affecting vehicle performance,
such as atmospheric conditions, rider weight, accessories, etc.
3-1
-------
None of the existing in-use or proposed procedures, in their present
form, satisfied the above criteria to the extent desirable in the intended
applications. Accordingly, variations of these procedures designed to
eliminate certain shortcomings of the existing procedures were explored.
A description and critique of each procedure appears on the following pages.
3.2 Candidate Moving-Vehicle-Test-Procedures
SAE J-331a (Moving vehicle acceleration test)
This test method, or variations of it, is the most commonly used
noise measurement procedure for motorcycles sold in the U.S., and is the
method for which the largest data base currently exists. It was therefore
the baseline method to which other candidate procedures were compared.
The procedure consists of approaching a marker at 30 raph or 60% of maximum
rated RPM* (whichever is slower), accelerating at full throttle commen-
cing at a point 25' before the microphone, and closing the throttle at a
point 100' past the microphone, or when maximum rated RPM is reached
(whichever occurs earlier). Second gear is used unless the vehicle travels
less than 50' before reaching maximum rated RPM, in which case third gear
is used. Six measurements on each side are taken, the highest and lowest
discarded, and the reported level is the average of four readings within
2 dB(A) of each other on the loudest side.
The full text of the procedure is presented in Appendix A. •
251
A. Approach at 30 raph or 60% RPM
(the slower).
251 75» B. Accelerate in 2nd gear unless 100%
_ ' RPM reached before zone C, in
which case use 3rd gear.
J C. Close throttle at 100% RPM or at
... , end of zone C (the earlier).
; i Microphone
*As used in this report, "maximum rated RPM" means the engine speed at
which "peak brake power" (as defined in SAE Standard J-245) is achieved.
Percent rpm is in reference to maximum rated RPM as 100%.
3-2
-------
Critique:
(a) The highest sound level achieved during a given test occurs at
different distances from the microphone for different motorcycles. This
means that for some motorcycles the highest sound level is measured, while
for others the measured level could be substantially less than the maximum.
This variable is influenced by horsepower, gear ratio and sprocket ratios.
Data on distance variability are presented in Appendix C, Table C-ll. To
a certain extent, this variability accounts for the differences in normal
operation of high and low powered motorcycles. However, it also results
in significant difference in measured levels among motorcycles having
almost identical characteristics.
(b) Some motorcycles, particularly the larger vehicles, do not reach
maximum rated RPM. In such cases, not only is maximum noise not developed,
but also, the highest sound level generated is at a point where the vehicle
is furthest from the microphone. Data on percent RPM attained are also
contained in Appendix C, Table C-ll.
(c) Due to vehicle and test variables, motorcycles of the same make and
model are not necessarily tested in the same gear. This could result in a
situation where a motorcycle was tested by the manufacturer using one gear,
and verified by a government agency using a different gear. The measured
levels could be substantially different in the two cases.
(d) Different size sprockets are available as options on most motor-
cycles, and are readily interchanged by the user. The 50 foot minimum
distance criterion makes the J-331a test sensitive to sprocket ratio. Thus,
the manufacturer could select a sprocket ratio which gives most favorable
results under this procedure, and supply to the user other sprockets for
various use applications. The practice of changing sprockets is widespread,
particularly in off-road or combination street/off-road motorcycles. The
important point here is that changing sprockets does not necessarily affect
substantially the actual generated noise, but can have major effect on the
measured level in the J-331a test.
(e) The procedure does not provide for the testing of motorcycles with
automatic transmissions.
(f) The procedure does not provide for the situation when, even in 3rd
gear, the vehicle does not travel the stipulated distance.
(g) Atmospheric conditions which affect power output will affect closing
R?M and/or vehicle position in relation to the microphone (in addition to
affecting sound power generated).
(h) Vehicle closing conditions (RPM and/or position) are affected by
rider weight, accessories weight, wind, and wind resistance.
3-3
-------
(i) This test procedure has the advantage of being independent of
tachometer dynamic characteristics for larger motorcycles (approximately
400-500 cc).
CHP Variation of J-331a (Moving vehicle acceleration test)
The California Highway Patrol (CHP) adopted the J-331a method for
type approval, with two variations:
(a) If maximum rated RPM is reached before 30 mph, or if a 50 foot
acceleration distance is not attained, the next higher gear is to be used.
(Other stipulations of J-331a apply.)
(b) Four instead of six measurements are required on each side of the
vehicle and the average of the two highest readings (within 2 dB(A) of each
other) on the loudest side are reported.
States which have adopted the CHP method are California, Colorado,
Floria and Oregon. States and cities which have adopted the J-331a method
are Maryland, Washington, Grand Rapids, Chicago and Detroit (Detroit
requires only two measurements on each side of the vehicle).
The full text of this procedure is presented in Appendix A.
Critique:
(a) Variation "a", above, will primarily affect the smaller motorcycles,
obviates certain test operation difficulties that may result "in over-revving,
and may be more representative of operational conditions for these vehicles.
Variation "b", based on test experience with measurement consistency, should
have no significant effect, and results in a simpler test procedure.
(b) The other shortcomings identified in the J-331a procedure critique
remain in the CHP variation of J-331a.
SAE J-986a (Moving vehicle acceleration test)
The J-986a procedure, although designed for passenger cars and light
trucks, is prescribed in Canada for the testing of motorcycles.
Major differences, referred to J-331a, are:
(a) Approach is at 30 mph in all cases.
(b) Sole criterion for gear selection is that the lowest gear which will
achieve the 50 foot acceleration distance shall be used.
(c) The end-zone is 100 ft. long, instead of 75 ft.
Full text of the procedure is presented in Appendix A.
3-4
-------
Critique:
(a) The speed and gear selection stipulations are not suited to some
motorcycles.
(b) The gear selection stipulation will result in full acceleration in
1st gear on the larger motorcycles, with attendant hazard factors.
SAE J47 (Moving vehicle acceleration test)
The J47 procedure was designed to measure the maximum noise potential
of the vehicle. It differs from the J331a procedure in the following major
respects:
(a) Instead of a variable end-point, a variable acceleration start-point
is employed, such that all vehicles reach rpm for peak power at a point 25'
past the microphone.
(b) The gear employed is the lowest gear that does not result in an
accelerating distance of less than 50' (for many motorcycles, this will be
first gear); however, when the above selected gear "results in a dangerous
or unusual operating condition such as wheel spin, front wheel lifting, or
other unsafe conditions, the next higher gear shall be selected...."
(c) Approach to the acceleration point is made at 60% rpm for peak power
in all cases.
Reporting method is the same as the J331a. The full text is pre-
sented in Appendix A.
Variable
"
25'
50'
Microphone
A. Approach at 60% rpm.
B. Accelerate in lowest gear such that
3C is not less than 50'. If this
results in unsafe condition, use
next higher gear. By trial, point
B is selected such that peak power
rpm is reached at point C.
C. Close throttle at end point C, 25'
past microphone point.
3-5
-------
Critique:
(a) The J47 test provides a more consistent measures of vehicle maximum
noie, since all vehicles reach peak power rpm at the same point in relation
to the microphone.
(b) Since the above condition does not prevail in the J331a test, corre-
lation between the two procedures cannot be expected, although maximum
differences by motorcycle category may be developed.
(c) As with J331a, motorcycles of the same make and model are not neces-
sarily tested in the same gear (due to vehicle and test variables). Gear
selection is further based on a judgment as to whether operation in that
gear is safe or not. However, in the J47 test the particular gear used
is of secondary in£»rtance, since in this test all motorcycles reach peak
power rpm at full throttle, and reach this condition at the same point in
relation to the microphone. The effect of gear selection on measured levels
was investigated during this study, with test results presented in Table 3-1
(F76 procedure description).
(d) Since in the J47 test gear selection is of only secondary signifi-
cance in relation to measured levels, then the matter oif sprocket options
(discussed in citique of J331a) is also not critical.
(e) The safety aspects of the J47 testing procedure are such as to
require a skilled rider familiar with the behavior of the particular
motorcycle, and exercise of care in its operation.
(f) The procedure is less sensitive to factors affecting vehicle per-
formance than is the J331a.
(g) The method has potential for precise correlation with a stationary
vehicle dynamometer test, since power output together with position in
relation to the microphone are defined.
The noise control regulations of Italy incorporate a noise test procedure
which in essense is the J47. Approach conditions are not prescribed, the
only stipulations being that 1st gear shall be used and that the vehicle
shall develop rated power and rpm when the vehicle is at the microphone
target point. Substitute methods of engine loading are permitted, such as
grade or dynamoneter.
3-6
-------
ISO/R-362 (Moving vehicle acceleration test)
The International Standards Organization, (ISO) Recommendation
R-362, "Measurement of Noise Emitted by Vehicles", was approved in May
1962 by the following ISO Member Bodies*.
Australia France Poland
Austria Germany Portugal
Belgium Greece Spain
Brazil Hungary Sweden
Canada India Switzerland
Chile Ireland United Kingdom
Czecholovakia Israel U.S.A.
Denmark Netherlands U.S.S.R.
Finland New Zealand Yugoslavia
The ISO/R-362 moving vehicle test procedure has since been incor-
porated into the regulations of the following countries:
France Portugal
Luxemburg Austria
Netherlands United Kingdom
Norway West Germany
Japan and Belgium have adopted a variation of the ISO/R-362 method.
The Economic Commission for Europe (ECE) has adopted the ISO/R-362 method
and has prescribed noise standards for various categories of motorcycles.
Sweden and Australia have'proposed revisions to the ISO/R-362.
In the test, approach is made at 75% rpm for peak power or 50 km/h,
(whichever is slower) . 2nd Gear is used if the vehicle is fitted with a
two-, three-, or four-speed gear box. If the vehicle has more than four
speeds, 3rd gear is used. The throttle is fully opened at a point 10 m
before the microphone point, and closed 10 m past the microphone point.
Provisions are included for the testing of vehicles with no gear
box, and for vehicles with automatic transmission.
Two readings within 2 dB(A) of each other are required on each side
of the vehicles, and the highest value reported.
Full text of the procedure is presented in Appendix A.
* "Approved" does not necessarily mean adoption into the regulations of
that country.
3-7
-------
A
IQm
B
IDm
7,5m C
^Microphone
A. Approach at 75% rpm or 5O km/h,
whichever is slower.
B. Accelerate in 2nd gear for
vehicles having up to four speeds,
3rd gear for vehicles having five
or more speeds.
C. Close throttle.
Critique:
(a) Hie test is simple, and subjective determination of proper gear
selection has been eliminated.
(b) A technical advantage is that acceleration termination is based on
vehicle position, not RPM, thus eliminating errors in closing RPM reading
or tachometer lag.
(c) The test was designed to be related to "normal town driving condi-
tions".
(d) Peak power will be developed on some vehicles, but not on others;
therefore, maximum sound level will be measured on some motorcycles, not
on others.
(e) sThe problem associated with sprocket options, as discussed in
critque of the J-331a procedure, is viewed as critical, and is not
addressed.
(f) Some off-road motorcycles are geared sufficiently low that they
will not travel the required 20 meters in the stipulated gear without
exceeding maximum rated RPM.
(g) To meet their special requirements, or to eliminate certain
problems encountered with the I90/R-362 procedure, various countries have
adopted or proposed modifications to the basic procedure. These are
discussed below.
3-8
-------
ISO/R362 Variations (Moving vehicle acceleration tests)
"Modified Method", Appendix A2 to ISO/R362-1964:
In this variation, the gear is selected which most closely results
in a vehicle speed of 50 km/h at 75% rpm, and approach is made at 75%
rpm. Itis further stipulated that if the vehicle has more than three
speeds, first gear shall not be used.
"ISO/R362 Proposed Amendment", 1974:
In this variation, approach is at 75% rpm or 50 km/h (whichever is
slower), except that if the speed corresponding to 50% rpm is less than
50 km/h, then entry shall be at the speed corresponding to 50% rpm. 2nd
Gear is to be used, unless 100% rpm is reached before the end of the
acceleration zone, in which case 3rd gear is to be used.
JASO Modification of ISO/R362:
This variation of the ISO/R362 procedure has been incorporated
into the regulations of Japan and Belgium. Modifications to the basic
ISO/R362 are in gear selection and approach speed:
JASO ISO/R362
Gear 2nd gear: 2nd gear:
Selection 2, 3-speed gr. box 2, 3, 4-speed gr. box
3rd gear: 3rd gear:
4-speed gr. box over 4-speed gr. box
4th gear:
over 4-speed gr. box
Approach
25 km/h: under 50 cc 50 km/h
Speed 40 km/h: 50-249 cc (or 75% rpm)
50 km/h: 250 cc & over
(or 75% rpm)
3-9
-------
"Second Draft Proposal", Revision of ISO/R362, May, 1975:
Major revisions, referred to the ISO/R362 procedure are:
(a) Vehicles haveing gear boxes of five or more speeds are to be tested
in both 2nd and 3rd gears, and the reported value is to be arithmetic
average of the two.
(b) The procedure for testing vehicles with automatic transmissions is
revised and expanded.
Critique:
(a) The numerous variations of ISO/R362, dealing mainly with approach
speed and gear selection, reflect the difficulty with this type of test
(where approach conditions, but not termination conditions, are controlled)
in arriving at a procedure that adequately characterizes the noise of a
broad range of motorcycles.
!/
(b) A very comprehensive study of motorcycle noise and test procedures
conducted in Japan compared noise emissions of a group of motorcycles as
measured by three variations of the ISO/R362 procedure (JASO, ISO, and ISO
Proposed Amendment). These variations, differing only in approach speed
and gear selection, yielded measured sound level variations up to 12 dBA,
showing the criticality of these parameters on measured levels. This also
indicates that a change in sprocket ratio will result in a change in mea-
sured sound level. (The Japanese investigators determined that the JASO
modification of the ISQ/R362 procedure yielded the best correspondence with
average noise due to average acceleration, as related to Japanese urban
traffic situations.)
P76 (Moving vehicle acceleration test)
While all of the foregoing test procedures can be considered as
candidates for use in the proposed EPA regulations, all of these proce-
dures were found to have shortcomings for new vehicle type approval.
Shortcomings fall in one or more of the following areas:
(a) Safety; hazard in testing (J47)
(b) Ambiguity; measured level dependent on gear selection involving
a subjective determination (J331a)
(c) Sprocket variables; measured level dependent on sprocket ratio
which is readily changeable; change in measured level disproportionate
to change in vehicle noise (J331a, ISO/R362)
3-10
-------
(d) Position variables; similar vehicles, differing only in gearing,
having noise measured at different distances from the microphone, or at
different rpm and power conditions (J331a, ISO/R362)
(e) Performance variables; atmospheric conditions, rider weight, or
accessories affecting vehicle closing rpm and/or position (J331a, ISO/
R362)
Representatives of the U.S. Suzuki Motor Corporation, and the
California Highway Patrol, submitted premliminary drafts of test proce-
dures designed to eliminate the above objections. These procedures,
together with other candidate procedures, were evaluated and refined in
the course of the study. The resulting procedure has been designated
F76, and consists of the following:
Approach is made at 50% rpm. The throttle is smoothly and fully
opened, commencing at a poin such that 75% rpm at full throttle is
reached at a point 25 feet past the microphone target point, at which
time the throttle is closed. Second gear is used, unless the acceler-
ating distance is less than 25 feet, in which case progressively higher
gears are used until the minimum 25 feet distance is attained. It is
further specified that if use of second gear results in a road speed in
excess of 100 km/h (62 mph), then first gear shall be used.
Full text of the procedure is contained in Appendix A.
Variable
T
25'
50'
f
.Microphone
A. Approach at 50% rpm.
B. Accelerate in 2nd gear from point
B, selected such that 75% rpm is
reached at point C. If BX is less
than 25', use next higher gear.
If speed at C is more than 62 mph,
use 1st gear.
C. Close throttle.
3-11
-------
Critque:
(a) Safety. The procedure does not require rapid opening of the
throttle; mandatory requirement is that wide open throttle at 75% rpm be
attained 25 feet past the microphone. No instances were encountered in
the entire test program where use of first gear was required; in any case,
use of first gear would not be hazardous under the prescribed operation
of the throttle.
The procedure results in many off-road motorcycles being tested
in third, and even fourth gear. Even in these higher gears, many off-
road motorcycles will exhibit front wheel lift-off under rapid throttle
opening. The procedure does not require this. Lift-off, however, is
not hazardous with these vehicles when operated by an experienced rider;
it is, in fact, a normal operational mode, used widely in the traverse
of obstacles in rough terrain.
(b) Ambiguity. Tests conducted in the course of this study show that
procedures which call for attainment of a specified condition of power
and rpm at a specified location in relation to the microphone (such as
J47, F76), are relatively insensitive to gear selection (Table 2-1).
(c) Sprocket variables. The relative insensitivity to gear selection
in the F76 test shows that a change in sprocket ratio will have little
effect on measured sound levels.
(d) Position variables. In the F76 test, the sound level, at the
specified power and rpm conditions, is always measured at the same dis-
tance from the vehicle.
(e) Performance variables. As with the other test procedures the
measured level in the F76 procedure will be affected by factors which
affect sound'power generated (such as relative air density); correction
factors could be applied for this. In contrast with the J331a procedure,
however, the F76 measured level is not affected by rpm/distance relation-
ships associated with variations in power output.
(f) Methodology substitution. Since the F76 test is conducted under
controlled conditions of power, rpm, and measurement distance, it can
be deduced that the means used to load the engine is relatively unimpor-
tant. For example, the same result should be obtained on a grade, or
on a suitable dynamometer, as long as the prescribed end-conditions are
attained. (The Italian procedure, which is similar to the J47, permits
3-12
-------
TABLE 3-1 EFFECT OF GEAR SELECTION ON MEASURED SOUND LEVELS
A dB^)Us1ng Next Higher Gear
Bike No. Category Qiscl.
101
103
109
119
126
123
127
130
131
132
134
135
146
*151
153
155
*160
161
*166
173
181
191
197
S
SX
X
S
S
sx
S
sx
S
S
S
sx
X
S
X
sx
S
sx
sx
sx
sx
sx
sx
356
123
248
398
184
249
738
98
371
543
246
173
246
949
248
98
736
247
72
397
183
242
J331a F76
-0.2
-1.3
-5.5
-1.7
-0.3
-3.2
0.2
-1.6 -0.3
-0.9
-1.7
0.9
-0.9 0
-3.7
-1.1
-2.6 1.0
-1.7
-3.3
-1.3
-4.0
J47
-0.6
-0.8
-0.1
0.3
*Automatic Hi-Range vs. Low-Range
3-13
-------
these substitutions in lieu of the prescribed acceleration test) . in
contrast, procedures such as the J-331a or the ISO/R-362 offer no possi-
bility of such substitutions as equivalents.
(g) Tachometers. Tachometer lag time can have an important effect on
the sound levels measured by F-976. Slow-responding tachometers will
result in engine speeds higher than those specified in the procedure as
occuring 25 feet past the microphone point. These higher engine speeds
will result in erroneously high sound levels being measured.
While it is possible to derive a statistical transfer function
between F-76 and J-331a (as has been done in the next section) it is not
possible to predict, for a particular motorcycle/ the F-76 level based
on the J-331a level using this transfer function. The reasons for this
are fundamental. For the smaller motorcycles, the J-331a level is depen-
dent of where in the end-zone the vehicle reaches 100% RPM. If it reaches
100% RPM near the start of the end-zone, the F-76 level (75% RPM) will
be lower; if it reaches it near the end of the end-zone, the two levels
will be about equal (differences in power being cancelled by differences
in distance). This in turn depends on gearing, and on which gear is used.
In the case of the larger machines, the degree of equivalence is dependent
on the value of the J-331a closing RPM. If the closing RPM is at a near
100%, the two levels will be near equal; if the closing RPM is well below
100%, the F-76 level will be higher. By making use of these factors,
together with vehicle performance data, it would be possible to estimate
F-76 levels for a particular motorcycle, based on the J-331a level.
For the aforementioned reasons, no close correlation should be
expected between the F-76 levels and J-331a levels. It was considered of
interest, nevertheless, to examine the degree of correlation, which is
presented in Figures 3-1 and 3-2. The surprising correlation in the case
of the off-road motorcycles is no doubt attributable to the fact that most
of these are small displacement, low-geared machines, and therefore reach
the acceleration end point near the microphone in both test procedures.
Note: In the initial drafts of this procedure, a 50 ft. minimum
acceleration distance was stipulated and employed. Difficulties occurred
in two areas—several of the smaller bikes could not attain the 50 ft.
distance before reaching 75% RPM even in the highest gear; others (350 cc
class off-road bikes) would not pull properly from 50% RPM in the gear
required to attain the 50 ft. distance. For these reasons the 50 ft.
minimum acceleration distance was changed (starting with bike No. 135) to
25 feet. The 25 ft. minimum distance stipulation presented no problems
in the testing of any of the motorcycles employed in the total program.
3-14
-------
I
_
5
tio
100
90-.
80-
70-
60
60
-1- 2 STROKE
D 4 STROKE
V = 17.37 + 0.793 X
r = 0.73
yx
= 2.9
70
90
100
I 10
J33U SOUND LEVEL, dBA
FIGURE 3-1 CORRELATION BETWEEN F-76 AND J331a TESTS, STREET
AND COMBINATION STREET/OFF-ROAD '75-'76 YR. OF MFG. MOTORCYCLES
3-15
-------
CS
•o
o
i
u.
no
100-
90"
80
70
60
60
+ 2 STROKE
n 4 STROKE
y « 2.93 •«• 0.943 X
r = 0.97
S = 1.72
yx
70
80
90
100
110
J331a SOUND LEVEL, dBA
FIGURE 3-2 CORRELATION BETWEEN F-76 AND J331a TESTS, OFF-ROAD
(ONLY) '75-'76 YR. OF MFG. MOTORCYCLES
3-1 fi
-------
F76a (Moving vehicle acceleration test)
In examining the noise emission data base (Section 4), in terms of
J331a levels (Figure 4-1)*, and in terms of F76 levels (Figure 4-3)*, it
is seen that the J331a method yields a regression line nearly flat (sound
level independent of displacement), whereas the F76 method shows a definite
upward slope of the regression line with displacement.
The reason for this is, of course, that in the J331a test the larger
motorcycles pass through the measurement zone without reaching rated power •
rpm, whereas in the F76 test all vehicles are measured at 75% rpm. The
ISO/R362 test is similar to the J331a tests is intentional, and recognizes
the fact that both in constant speed and in accelerating modes the smaller
machines will usually be operated closer to their maximum potential than
will the larger machines. This is not only because of available horse-
power, but also, in the small machines characteristically the torque curve
is steep, favoring operation at high rpm, whereas in the large street
machines the torque curve is relatively flat, resulting in acceptable per-
formance at lower rpm's.
To take this factor into account, a variation of the F76 method,
designated F76a, was investigated. The F76a procedure differs from the
F76, in that instead of testing all vehicles at 75% rpm, the test rpm is a
function of displacement. The rpm/displacement relationship developed in
the study was:
y - 90 (0 -100 cc) where y - % rpm
95 - .05x (100-700 cc) x - displacement, cc
60 (700+ cc)
This relationship, shown graphically in Figure 2-3, yields a test
rpm of 90% at 100 cc, reducing to 60% at 700 cc. Above 700 cc the closing
rpm remains constant at 60%. Entering rpm is 50% or 20 percentage points
below closing rpm, whichever is lower.
Basis of the F76a rpm/displacement relationship is the data
collected in the course of the test program where a number of motorcycles
were tested at more than one closing rpm. These data appear in Appendix
Cf and in Tables C-ll and C-12 and are summarized in Table 3-1 and Figure
3-4 in this Section.
*Figures pertaining to the noise emission data base are presented in
Section 4.
3-17
-------
r
M
CO
100
80
60
I 40
PM
20
y « 95 - O.OSx
0 200 400 600 800 1000 1200
DISPLACEMENT - cc
FIGURE 3-3. CLOSING KPM FOR F76a MOVING VEHICLE ACCELERATION TEST
-------
TABLE 3-2. COMPARISON OF F-76a AND J-331a SOUND LEVELS
Displacement Mean Sound Level, dB(A) Std. Deviation Number of
Range Vehicles in
cc F-76a J-331a F-76a J-331a Sample
100
175
350
550
900
- 125
- 250
- 400
- 750
- 1200
80
80
82
82
82
.8
.8
.5
.3
.6*
80
80
81
81
80
.9
.9
.1
.9
.6
2
1
1
1
1
.57
.73
.77
.38
.91
2
2
3
0
3
.62
.34
.55
.71
.58
10
8
6
6
4
The vehicles in this sample are unmodified '75 - '76 yr. of mfg.
street and combination street/off-road motorcycles. The F-76a levels have
been derived by interpolation or extrapolation of sound levels measured
at RPM's other than the F-76a RPM. The J-331a levels are directly measured
data.
*This small sample of 4 included two vehicles whose F-76 level was con-
siderably higher than the average of other vehicles in this category.
3-19
-------
CD
3 +5
o
(/i
nj
CO
a
e
4)
_J
•a ~*
o
r*.
i
u.
.
«
*
-**""••
• .
. "~"
•• -
.
• --~ "
•
*
\*~ "^
*^ -
"* •
,
— * ""
^- -* •
•
-p-
«
F-76 sound levels for
motorcycles represented
1n Table C-12
200
500
700
850
1200
03
O
V)
«.... o-
-5
0
•
.
'
200
•
.
•
•
*
F-76a sound levels fro
4
n
linear interpolation and
extrapolation of data in
Table C-12
500 700 850 1200
01splacement"C.c.
FIGURE 3-4. CCMPARISCN OF F76 AND F-76a SOUND LEVELS
3-20
-------
Figure 4-5* shows the difference between F-76 and J-331a levels
plotted against displacement, with the upward sloping regression line
showing that statistically the F-76 level is higher than the J-331a level
for large motorcycles, lower for small motorcycles. Referring again
to Table 3-2, it is seen that while a larger statistical sample of F-76a
test data desirable/ the data indicate that if F-76a data were substituted
for F-76 data, the regression line would not only be independent of displace-
ment, but would also be numerically approximately equal to the J-331a
levels on a statistical basis.
A curve of sound level vs. closing RPM for one motorcycle is shown
in Figure 3-5.
A secondary advantage of the F-76a procedure over F-76 is that lower
testing speeds result on the large motorcycles. In the F-76 test, speeds
of up to 55 mph were encountered in this study. This would reduce to about
45 mph in the F-76a test. Manufacturer test data show tire noise of 66 dB(A)
at 45 mph on a 750cc motorcycle, indicating that tire noise would not be
a significant contributor to total vehicle noise in the F-76a test.
Text of the F-76a procedure is presented in Appendix A.
R-6Q (Moving vehicle acceleration test)
With the same rationale basic to the F-76a test, a staff member of
AMF Barley-Davidson submitted (prior to development of the F-76a test)
a candidate moving vehicle acceleration test procedure designated R-60.
The R-60 test is similar to the F-76a except that the closing RPM employed
is the RPM corresponding to 60 mph in top gear (instead of 75% RPM for
all vehicles). Entering RPM is 75% of the closing RPM.
A full text of the procedure is presented in Appendix A.
Critique:
(a) The procedure does not provide for the testing of vehicles which
do not reach 60 mph; this difficulty could be eliminated by adding the
stipulation that vehicles which reach 100% RPM before 60 mph shall be
tested at 100% RPM.
*Figures pertaining to the noise emission data base are presented in
Section 4.
3-21
-------
90
86"
a
o
84 •-
82-
80
F76 LEVEL
F76a LEVEL
50
4-
The 75% rpm data point was
obtained using the F76 test
procedure. The test procedure
used to obtain the other data
points was the same except
for closing rpm, which was
varied as shown on the plot.
60
70 80
PERCENT RPM
90
100
FIGURE 3-5 EXAMPLE OF SOUND LEVEL AS A FUNCTION
OF PERCENT RPM (HARLEY XLH-1000)
3-22
-------
(b) Similar vehicles, differing only in gearing, could be tested at
substantially different RPM's yielding substantially different measured
levels.
(c) Changing sprockets would result in testing at different RPM's,
with resultant different measured levels.
(d) Some street motorcycles are capable of very, high speeds. A
motorcycle with a top speed of 135 mph would be tested at 44% RPM, a
rather low test RPM.
(e) The F-76a procedure provides an alternative means of dealing with
the different operational situations of the small and large machines,
and avoids the difficulties appearing in the R-60 method.
F-77 (Full speed, full throttle, moving vehicle test)
In lieu of the ISO/R-362 acceleration test, Norway prescribes a
full speed, full throttle pass-by test for mopeds. In the course of the
study, this procedure was examined for motorcycles up to 100 cc; above
that some vehicles reach excessive speeds.
This is a considerably simpler test to run than any of the other
moving vehicle procedures, requires no tachometer or speedometer, and is
representative of common operational conditions for the under-100 cc
vehicles. It yields levels usually close to the J-331a levels, and can
be expected to yield.levels close to the F-76a test.
Full text of the procedure is presented in Appendix A.
Problem Areas: Moving Vehicle Test Procedures
(1) Automatic Transmissions
Automatic transmissions are coming into use increasingly in both
street and off-road motorcycles, large and small. In the course of the
study the following motorcycles with automatic transmissions were tested:
Street
Moto Guzzi V1000 Converter
Honda CB750A
Honda NC-50
Off-Road
Rokon 340 RT
Husqvarna 360 Automatic
3-23
-------
Combination Street/Off-Road
Yamaha Chappy (minibike)
Mopeds
NT7 Model ERB
Kreidler MP3
Vespa Ciao
Motobecane Mobylette
Velosolex 4600
Peugeot 103LVS.U3
Difficulty in varying degrees was encountered in testing the
motorcycles with automatic transmissions. The Moto Guzzi V1000 and the
Honda CB750a incorporate a high and low-range selection; low range pro-
duces significantly higher levels in the J-331a test, high-range use in
the F-76 test results in excessive speed. For the F-77 test, however,
high-range should be specified; otherwise the engine can over-rev.
The Rokon 340RT and the Husqvarna 360 Automatic present testing
problems which were not resolved in the course of this study. The Rokon
340RT incorporates a variable ratio belt drive, the driving member acted
upon by centrifugal forces, the driven member affected by reacting torque.
The drive ratio is determined by both engine rpm and torque demands.
There are no selectable options for the rider, other than throttle position.
The J-331a test procedure, as written, does not provide for the testing of
vehicles with automatic transmissions. However, if the gear stipulation
is ignored, what appears to be a meaningful J-331a test can be run. To run
an F-76 test, however, an entirely different technique is required: the
throttle must be opened very gradually in order not to immediately exceed
75% RPM"; with some practice, vehicle speed can be smoothly increased such
that 75% RPM at full throttle is attained at the required end point, with
good consistency among the six passes. As discussed in Section 3.2,
vehicles which reach 100% RPM near the end of the end-zone in the J-331a
test exhibit near equal J-331a and F-76 levels. The Rokon 340RT fits this
pattern, reinforcing the appropriateness of the above testing techniques.
The Husqvarna 360 Automatic incorporates four centrifugal clutches,
with Sprague roller clutches which permit the lower geared centrifugal
clutches to freewheel when the higher geared clutches engage. The J-331a
test cannot be run, because 100% RPM is reached well before the start of
the end-zone, and no rational criteria exists for regulating the throttle
other than wide open. Within the time constraints of the study, no tech-
nique was developed which would achieve full throttle at 75% RPM at the
3-24
-------
prescribed point in relation to the microphone. Further analysis and testing
will be required to develop a meaningful and repeatable test technique for
this type of vehicle.
Based on the testing of two under-100 cc motorcycles, and six mopeds,
no problems appear in testing the under-100 cc vehicles with automatic
transmissions under the F-77 procedure.
(2) Tachometers
A major problem encountered throughout the test program was in
obtaining engine RPM readings on motorcycles not equipped with tachometers.
Portable tachometers used in the program included the Sanwa Model MT-03,
the Rite Autotronics model 4036, and the Dynall Mode TAG 20. In most
cases, one of these three tachometers could be made to function properly
on the test vehicle, but none of these tachometers would work on all motor-
cycles. In some cases the testing of a motorcycle was abandoned because
of inability to obtain proper functioning of the tachometer.
A vehicle manufacturer should have no difficulty in arriving at a
suitable tachometer or other means of determining RPM for his particular
line of vehicles; the problem exists primarily for the EPA and for after-
market manufacturers, where universal application over many makes and
models would be necessary. Fortunately, however, the steady-state accuracy
of the tachometer (either the vehicle tachometer or a portable tachometer)
can be readily verified simply by matching the engine firing frequency
(as picked up by a wire placed in proximity to a spark plug lead) with
a signal from a calibrated oscillator, the two signals being matched
on an oscilloscope.
A second factor to be considered in the use of tachometers for
moving vehicle acceleration tests is tachometer lag, and the ability of
the rider to close the throttle at the correct RPM. This effect was
evaluated in a previous study—', where results obtained using the vehicle
tachometer were compared with results obtained using an electronic tacho-
meter incorporating a "max. hold" mode (Emission Control Instruments,
Precision Tachometer). In that study, when the rider performed J-47 tests
on ten motorcycles using the vehicle tach for reference, the true RPM
recorded by the electronic tach ranged from 1132 RPM high, to 356 RPM low,
as compared to the intended RPM. When the J-47 tests were repeated with the
closing RPM at the proper value established by the electronic tach, measured
levels ranged from zero to 2 dB(A) lower.
3-25
-------
Test methodologies such as the J-331a and the F-76 (as opposed to the
ISO/R-362 type) are subject to both the problems of tachometer functional
compatibility and lag, unless other methods are established to measure
engine speed. The dynamometer method is free of these problems, since
the tachometer can be incorporated into the dynamometer, and measuring
conditions are steady-state.
3.3 Candidate Stationary Vehicle Test Procedures
F-50 (Stationary vehicle test)
The F-50 procedure is patterned after the ISO proposed draft, "Method
of Control of Noise Emitted by Stationary Motor Vehicles," July 1974. The
test consists of running the engine up to 50% RPM, unloaded, and measuring
noise at a distance of 0.5 m from the exhaust outlet, on a line displaced
45° from the exhaust axis. The complete text of the procedure and also
the ISO draft are presented in Appendix A.
Critique:
The F-50 levels, presented in Section 4, are relatively independent
of displacement (Figure 4-7 and 4-8) and have been correlated with J-331a
and F-76 levels in Figure 3-6 thru 3-9. The correlation is not sufficiently
good as to permit the moving vehicle acceleration noise for a particular
vehicle to be predicted from the stationary level. Major reasons for
this are that the engine is not under load, and thus exhaust noise is
not representative of the acceleration conditions, and because the throttle
is only partially open, intake noise is not fully developed.
The test is nevertheless of potential value. Figures 3-10 and 3-11
show that in general an exhaust system change which produces higher moving
vehicle sound levels also results in higher levels in the stationary test.
The correspondence in this respect is sufficiently good that the method
could be used for on-the-road enforcement against exhaust system tampering.
The figures show that the method would be quite effective against flagrant
violators, providing the OEM (original equipment manufacturer) value was
known and labeled on the machine.
3-26
-------
120
119-
TOO-
o
i/i
g
90-
80-
+ 2 STROKE
D 4 STROKE
y = 28.79 + 0.764x
r = 0.64
. = 3.73
70*
60
70
80
90
TOO
0331 a SOUND LEVEL, dBA
FIGURE 3-6 . CORRELATION BETWEEN F-50 AND J331a
TESTS, 1969 - 1976 MODEL STREET AND COMBINATION
STREET/OFF-ROAD MOTORCYCLES
110
3-27
-------
120
no..
100..
90..
o
in
80..
+ 2 STROKE
O 4 STROKE
y « 24.88 + 0.78x
r * 0.73
yx
4.85
70
70
-4-
80
4-
-H-
90
4-
60
100
no
0331a SOUND LEVEL, dBA
FIGURE >7 CORRELATION BETWEEN F-50 AND J331A TESTS,
1969 - 1976 MODEL OFF-ROAD (ONLY) MOTORCYCLES
3-28
-------
120
no-.
+ 2 STROKE
n * STROKE
<
=z
100-.
UJ
UJ
e
M
-
.-,
i
80-.
4- a
60
70 80 90
F-76 SOUND LEVEL, dBA
100
no
FIGURE 3-R CORRELATION BETWEEN F-50 AND F-76 TESTS,
1969 - 1976 MODEL STREET AND COMBINATION STREET/OFF-ROAD
MOTORCYCLES
3-29
-------
tn
o
tn
i
120
110 -•
too..
90'•
80"
70
60
FIGURE 3-9
+ 2 STROKE
D 4 STROKE
a
y = 19.82 + 0.855x
r = 0.77
S = 4.63
yx
70
80
90
100
110
F-76 SOUND LEVEL, dBA
CORRELATION BETWEEN F-50 AND F-76 TESTS, 1967 - 1976
MODEL OFF-ROAD (ONLY) MOTORCYCLES
3-30
-------
•a
*
ui
30-
25-
20-
15-
10-
5
0
-5
D
I
D
DC
DDE
D
*^M ^M» «••. *~^
I
a
a i
a
a
+ 2 STROKE
D
Q 4 STROKE D
a
DD D
ODD
D
D D
a
D a D
a
a a
DD D D D
D D D
DDB3D D
D fflD D D
D DO D
DD D +
3 DDD D „
} D DEB D a
3D D D
5ao
Taa
JIDD
1
1 , — , — ^ — i — i j
•5
0 5 10 15 20
CHANGE IN J33U SOUND LEVEL, dBA
FIGURE 3-10 CORRELEATION BETWEEN CHANGE IN F-50 SOUND LEVEL
COMPARED TO CHANGE IN J33U SOUND LEVEL, AFTERMARKET AND MODIFIED
CONFIGURATIONS REFERRED TO ORIGINAL MANUFACTURE
3-31
-------
CD
•o
ft
•
LU
UJ
a
Z3
V?
o
LT>
U.
z
1-1
LU
C3
«C
O
30-
25-
20-
15-
10-
5
0
-5
a
t
at
ai
a
a
a
5
+ 2 STROKE a
Q 4 STROKE n
a
a a
a
a aa
aa a
a
a a
a
aaa
a
a a
a a a a
aaa a
a fflaa aa a
a +aa a
a aa
aaa a +
& aaa
a-faa aa
aaa a
gaa
a aa
a
ia i i i i "
6 5 10 15 20 25 3
CHANGE IN F-76 SOUND LEVEL, dBA
FIGURE 3'11 CORRELATION BETVJEEN CHANGE IN F-50 SOUND LEVEL
COMPARED TO CHANGE IN F-76 SOUND LEVEL, AFTERMARKET AND
MODIFIED CONFIGURATIONS REFERRED TO ORIGINAL MANUFACTURE
3-32
-------
A further alternative to the F-50 test, for use by the exhaust
system manufacturer, could be the dyne-simulation of the moving vehicle
test, as discussed later in this section.
Motorcycle Industry'Council (MIC) Proposed Field Test Procedure
for Sound Levels of Competition Motorcycles, Rev. 1-30-76
This procedure, the full text of which appears in Appendix A, is
similar to the F-50 procedure, differing mainly in features which make it
more convenient for application in competitive events. Test RPM is 50%
red-line, alternatively 60% maximum rated RPM, or alternatively calcu-
lated from a formula as a function of stroke dimension.
Critique:
(a) The features of this procedure (which enhance its usefulness in
the intended application) introduce a lack of precision not desirable in
EPA applications.
(b) The procedure provides for the testing of motorcycles not having
a "neutral" transmission position; this is accomplished by raising the
rear wheel or removing the chain.
F-76 Dyno-Simulation (simulated moving vehicle acceleration test)
A cursory investigation of the feasibility of simulating moving
vehicle acceleration tests on a dynamometer was conducted, using one
motorcycle (Honda CE 750) and a Pabatco Dyno (made by Weda Instruments).
This dynamometer is one of the lowest priced portable units commercially
available, not specifically designed for noise testing, and not incor-
porating any quieting provisions (Figure 3-12). The motorcycle was
successively fitted with seventeen different exhaust systems, which
resulted in F-76 levels ranging from 82 to 98 dBA. For the dyno-
siiaulated F-76 test, the dynamometer was set up at the test site at the
F76 test track end point, with the microphone positioned as it would be
for the actual F-76 test moving vehicle test. Sound level as measured at
75% RPM at full throttle was established, a procedure taking about 15
seconds. Figure 3-13 presents the correlation of results from this test
and the actual F-76 moving vehicle test. Readings were taken only on the
left side of the motorcycle, even though some of the exhaust systems were
on the right side only; this because the dynamometer configuration
precluded taking readings on the right side.
3-33
-------
I
nk« iVaifjtfri
FIGURE 3-12 PABATCO DYNAMOMETER
-------
no
CQ
•0
LU
Ul
o
CO
tx
I
Q
LLl
90..
80..
70..
60
60
y = 1 .072x - 5.474
r = 0.94
yx
H 1 1 1 h-
70 80 90
F-76 SOUND LEVEL, dBA
TOO
FIGURE 3-13 CORRELATION BETWEEN DYNO-SIMULATED F-76 TEST, AND ACTUAL
F-76 MOVING VEHICLE TEST
3-35
-------
Potential advantages of the dynamometer test method include:
- lower testing cost
- removal of schedule constraints due to weather
- greatly reduced area requirements
- no transportation of vehicles to and from test site
- greater accuracy by testing at a steady state condition rather
than at a changing condition
- no problems with tachometer functioning, accuracy, or lag
- removal of testing variables such as throttle closure, distance
determination
- removal of wind, weather, micro-meteorological variables
- minimization of site variables
As discussed in Section 3.2, dyno-simulation of the J-331a or
ISO/R-362 test procedures is not feasible.
3.4 Measurement Distance Substitution
All of the noise emission data presented in this report were mea-
sured at a 50-foot distance (except the F-50 data, which were measured at
0.5 m), as delineated in the respective procedures. An investigation was
made, however, to determine feasibility of taking measurements at 25 feet,
and correcting the measured values to a 50-foot equivalent. Results of
this investigation are shown in Table 3-3 and Figures 3-14 and 3-15; it
is evident that no such conversion is possible in the case of an accele-
ration test (as opposed to a constant speed test).
The reason for the lack of correspondence between the 50-foot and
25-foot measurements was not investigated; it may be that the vehicle noise
exhibits a changing polar pattern as the vehicle accelerates, such that a
lobe changes in magnitude as it passes from one microphone to the other,
or it may relate to a changing interference relationship (discussed in
section 4.2} resulting from spectral changes as the vehicle moves past
the microphones with changing RPM.
3-36
-------
TABLE 3-3 RELATIONSHIP BETWEEN 2b FT. AND 50 FT. SOUND LEVEL MEASUREMENTS
BIKE
NO.
101
162
103
104
105
109
no
in
112
113
114
115
117
118
119
120
140
141
142
143
1 145
146
145
151
151
152
1 155
155
156
157
158
159
160
160
160
161
161
162
DISPL.
CC '
356
72
123
999
736
248
124
171
99
248
99
99
99
174
400
746
828
49
744
246
981
246
246
949
949
336
98
98
72
49
898
750
736
736
736
247
247
124
ncl 903
ENGINE
FYPE
4 S
4 S
2 S
4 S
4 S
4 S
4 S
2 S
4 S
4 S
2 S
2 S
2 c
2 S
2 S
4 S
4 S
2 ^
4 S
2 S
4 S
2 5
2 S
4 S
4 S
2 S
2 5
2 S
2 S
2 S
4 S
4 S
4 S
4 S
4 S
2 S
2 S
2 S
4 S
DIFFERENCE BETWEEN 25 FT AND 50 FT
SOUND LEVEL READINGS, dBA
J331a
5.6
3.1
5.0
5.8
7.6
5.0
1.6
2.1
2.8
3.5
4.6
3.1
4.0
3.5
4.5
6.3
6.5
5.1
3.6
7.3
6.7
5.5
4.6
4.3
3.5
5.8
5.4
4.4
5.2
6.9
4.8
5.9
F76
6.2
4.3
5.4
1.9
4.1
4.1
4.8
3.8
5.0
6.0
5.4
7.2
6.9
5.3
5.9
5.3
7.3
4.1
4.6
8.1
6.1
4.7
6.8 1 5.8
7.1 1 6.6
1
F77
5.0
1
5.3
6.5
Rfif)
55 MPH
.6.6 ,
4.7
6.6
7.0
6,6
6.0
5.2
3-37
-------
10-r
UJ
00
UJ
UJ
o
in
UJ
ui
o
o
in
CM
9
8
7
6
S 5"
4--
2
1
0 +
a
D
a
a
a
a
J2L
cP
a
D
a
a
a
2 STROKE -H
4 STROKE r:
+
+
+
-f-
+
+
4-
+
100
200 300
400
500 600
700
800
900
1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 3-13 DIFFERENCE BETWEEN 50 FT AND 25 FT MEASURED SOUND LEVELS DURING ACCELERATION
(J331a AND F-76) TESTS
-------
UJ
ui
o
o
to
9"
8"
7--
a a
O
in
5--
I
co
UI
a
o
in
m
cvj
4-.
3--
O • »
2 STROKE +
4 STROKE D
—I—
100
-
4
0
200 300
800 900 1000 1100 1200 1300
400 500 600 700
DISPLACEMENT, cc
FIGURE 3-14 DIFFERENCE BETWEEN 50 FT AND 25 FT MEASURED SOUND LEVELS DURING CONSTANT
SPEED (35 MPH AND 55 MPH) TESTS
-------
SECTION 4
SOUND LEVEL DATA BASE
-------
Section 4
SOUND LEVEL DATA BASE
4.1 Content and Format of the Data Base
The basic motorcycle sound level data base used for this regulation
is presented in Appendix C. Sound data for the following are included:
(a) 159 new 1976 model year motorcycles (year of manufacture 1975 and
1976);
(b) 60 year of manufacture 1974 motorcycles in stock configuration;
(c) 257 in-service motorcycles in stock configuration, year of manu-
facture 1969-1973 (includes the data developed in the MIC motorcycle testing
program);
(d) 43 in-service modified motorcycles, year of manufacture 1969-1976;
(e) 107 motorcycles with new aftermarket exhaust systems.
Motorcycles*in group "a" above provide the best sound level baseline
for assessing cost and economic impact of adoption of standards more stringent
than 83 dBA (for street motorcycles) which is the standard currently in effect
in some states (e.g., California). Street motorcycles manufactured prior
to 1975 have been subject to less stringent standards and are therefore not
representative of current technology applications and cost.
Off-road motorcycles in groups "a", "b", and "c" can be included
in the baseline data for off-road category, since regulation of noise
emissions from those vehicles has been very limited.
Motorcycles in group "a" through "d" provide a baseline for
assessing environmental improvement that can result from regulation of
the new vehicle, the aftermarket product, and user modifications.
Motorcycle aftermarket data, group "e", show the degree to which
currently offered-for-sale aftermarket exhaust systems affect new vehicle
noise emissions.
The total sample of vehicles, groups "a" through "e" above, were
enployed in the development and/or evaluation of test methodologies
(Section 3) in the course of acquiring the data base.
4-1
-------
The following makes and models are represented:
Benelli 750 SEI
BMW R90/6
Bf1W R90S
BMW R60/6
Bultaco 250 Alpina
Bultaco Frontera
Bultaco 350 Sperpa T
Bultaco Matador MK9
Bultaco 250 Pursang
Can Am 125 TNT
Can Am 250 TNT
Can Am 250 MX!
Carabela 125 Marquesa MX
Carabela 250 Centauro
Ducati DM750S
Garelli Moped
Harley FXE-1200
Harley FLH-1200
Harley SSI25
Harley SSI75
Harley SS250
Harley SX125
Harley SX175
Harley SX250
Harley XLH1000
Hodaka Road Toad
Hodaka 250
Honda CB 400F
Honda CB SOOT
Honda CB 750A
Honda CB125S
Honda CB1255
Honda CB200T
Honda CB350F
Honda CB360T
Honda CB450
Honda CB550
Honda CB550F
Honda CB500T
Honda CB750
Honda CB750F
Honda CJ360T
Honda CL360
Honda CL450
Honda CR125M
Honda CT70
Honda GL1000
Honda MR50
Honda MR175
Honda MR125
Honda TL250
Honda XL70
Honda XL70K2
Honda XL100
Honda XL125
Honda XL175
Honda XL250
Honda XL350
Honda XR-7b
Honda Z50A
Honda All Terrain
Honda CT90
Honda NC50
Husqvarna 360 Automatic
Husqvarna 360URX
Indian MT175
Kawasaki 900Z1
Kawasaki KD80
Kawasaki KE125
Kawasaki KE175
Kawasaki KH 100
Kawasaki KH 250
Kawasaki KK 400
Kawasaki KM 100A
Kawasaki KT250
Kawasaki KV75
Kawasaki KV100
Kawasaki KZ400
Kawasaki KZ400D
Kawasaki KZ400S
Kawasaki KZ750
Kawasaki KZ900
Kawasaki KZ900LTD
Kreidler MP3
Laverda 750SF
Laverda lOOOThree
Montesa. 250 Enduro
Montesa Cota 123
MontesA Cota 247
Montesa. Cota 348
Motobecane Mobylette Moped
Moto Guzzi 1000 Convert
Moto Morini 3 1/2
Moto Guzzi 850-T
Norton 860 Commando
NVT ERB Moped
Ossa Desert Phantom 250
Ossa 250 Pioneer
Ossa 350 Plonker
Peugeot 103 LVS V3
Rokon RT-340 11
Suzuki GT185
Suzuki GT380
Suzuki GT500T
Suzuki GT550
Suzuki GT750
Suzuki RE-5 Rotary
Suzuki RM125
Suzuki RV90
Suzuki TM75
Suzuki TS100
Suzuki TS185
Suzuki TS400A
Suzuki TS400S
Velosolex 4600 Moped
Vespa Ciao Moped
Yamaha Chappy
Yamaha DT100C
Yamaha DTI75
Yamaha DT175C
Yamaha DT250
Yamaha DT250C
Yamaha DT400C
Yamaha DT650C
Yamaha f 1X125
Yamaha RD125B
Yamaha RD200B
Yamaha RD200C
Yamaha RD250
Yamaha RD350
Yamaha RD400C
Yamaha RS100B
Yamaha TX750
Yamaha TY80
Yamaha XS360C
Yamaha XS650B
Yamaha *S650C
Yamaha XT500C
Yamaha XT500
Yamaha YZ125C
-------
The vehicle population tested encompasses street, off-road, and
combination use motorcycles; 50 to 1200 cc displacement; 2-stroke, 4-stroke
and rotary engines; 1, 2, 3f 4f and 6 cylinders; manual gear shift, automatic
clutch, hydraulic torque converter, and centrifugal torque converter trans-
missions; a few mopeds are also included.
Test methodologies employed in acquiring the data base include the
J-331a, F-76, and R-60 acceleration tests; the F-77 full-speed/full-throttle
test for under-100 cc bikes; the F-50 stationary vehicle test; and a dyno-
simulation of the F-76 test. These test procedures are described in
Section 3 and detailed in Appendix A. Sound levels at 35 mph and 55 mph,
constant speed pass-by, have also been obtained on a representative group
of vehicles.
The sound level data base of new '75-"76 year of manufacture
motorcycles is presented primarily in terms of J-331a, F-76, and F-50 noise
measurements. The data base is presented graphically in Figures 4-1 thru
4-10, and in tabular detail in Appendix C. Format of the graphical pre-
sentations is as follows:
(a) J-331a levels vs displacement — Figures 4-1 and 4-2
(b) F-76 levels vs displacement — Figures 4-3 and 4-4
(c) Transfer function F-76:J-331a, by displacement category and overall —
Figures 4-5 and 4-6
(d) F-50 levels vs displacement — Figures 4-7 and 4-8
(e) 35 mph steady speed levels vs displacement — Figure 4-9
(f) 55 mph steady speed levels vs displacement — Figure 4-10
Tabular detail of noise emissions presented in Appendix C includes
not only that for new '75-'76 year of manufacture motorcycles, but also
similar data for '69-'74 in-service motorcycles, motorcycles with modified
exhaust systems, and data on aftermarfcet products. The tabular presenta-
tions include:
(a) Sound levels (J-331a, F-76, R-60, F-77, F-50, 35 mph, 55 mph) by
displacement and use categories; new motorcycles, year of manufacture
•75 and '76: Table C-4.
(b) Same data as Table C-4; by manufacturer: Table C-5.
(c) Sound levels (J-331a, F-76, F-77, F-50, 35 mph, 55 mph) by displace-
ment and use categories; in-service motorcycles, year of manufacture '69-'74,
in stock configuration: Table C-6.
4-3
-------
ICU
110
CO
"^ 100
Ul
LU
Q
1 90-
CO
«o
CO
"3
80 :
70-
60-
*
x«78.0 x.81.5 ST m 83.1 7-80.6 ~ - 81 4
o - 4.44 o « 2.95 o « 4.49 - a • 2.99 0 . 3.9*6
n • 15 n • 10 n • 23 n - 45 n - 28
•7
.«
/
^^
M
l"l i llJ •"
•HW I UJ
•' /
+
.
+
8v # !
7
h
+± D H
f « B B A
\ 2 STROKE +
4 STROKE D
D y- 80.55 + 0.00079x
D D
a D n B
I on n i
4-aba E d rlDn
T T ffl _— i^ II — •
of a K . tf e
D
•^ LJ
4-
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 4-1 J331a SOUND LEVELS. STREET AND r.nMRTNATtnN CTDCCT / ncc nn/m ,-,c ,,.
MOTORCYCLES
- '76 YR. OF MFG.
-------
120*
a
o
o
CO
01
y * 82.23 + 0.026x
-4-
500
—f—
600
2 STROKE 4-
A STROKE n
4-
4-
•4
700
800
900 1000 MOO 1200 1300
DISPLACEMENT, cc
FIGURE 4-2 J331a SOUND LEVELS, OFF-ROAD (ONLY) '75-'76 YR. OF MFG. MOTORCYCLES
-------
to
7
2 STROKE +
4 STROKE O
y » 15.1 + 0.01 x
700
1200 1300
FIGURE 4-3
DISPLACEMENT, cc
F-76 SOUND LEVELS, STREET AND COMBINATION STREET/OFF-ROAD
'75 - «76 YR OF MFG MOTORCYCLES
-------
o
co
to
r^
i
120-
no-
ioo-
90-
80-
70-
60^
x - 76
a • 1.
n - 5
•1"
*
^
.^^
t^^
*
.4
32
~ 1
m
x " 88.7 ^
a - 10.4 (
1*3 i
"t
-
b*
^^l +
4.
•
a
• i i
«* 86.8
7 - 5.34
1 - 16
r
y - 79.54 + 0
^
h
i i i ii
0262x
2 STROKE -f
4 STROKE D
) 100 200 360 40'0 500 606 700 800 900 1000 1190 1200 1300
FIGURE 4-4
DISPLACEMENT, cc
F-76 SOUND LEVELS, OFF-ROAD (ONLY) '75 - '76 YR. OF MFG. MOTORCYCLES
-------
V)
10
1
z
UJ
CO
J8
-1.82 x - -1.82 x - -1.27
1.94 a • 1.89 a • 1.80
11 n • 11 n « 22
y • -2.48 + 0.0066x
2 STROKE +
4 STROKE D
1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 4-5 COMPARISON OF F-76 AND J33la SOUND LEVELS, STREET AND COMBINATION
STREET/OFF-ROAD '75 - '76 YR OF MFC MOTORCYCLES
-------
10
UJ
Ul
o
st
o
as
fO
"3
r»
z.
HH
s:
_i
UJ
>
Ul
o
i
o
10
tx.
I
5 •
-5 -
-10
TT *
A • ^ |
'o - 1.
•n • 4
• i
»
•
»
•H-
•— —
O
•
0 1C
.5 x
0 a
n
T
fl
+
.
)0
- -2.0 x
« 1.73 o
•3 n
1
r
1
•f +
H T^
.
• +
a
h—
200 300
. -2.0
« 1.83
- 16
i
h y
400 5(
.
= - 2.21 + 0.0012x
'
JO 600 700
2 STROKE •+
4 STROKE D
800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 4-6 COMPARISON OF F-7G AND J33U SOUND LEVELS, '75 - '76 YR OF MFG
OFF-ROAD (ONLY) MOTORCYCLES
-------
I
M
O
120 T r
x
a
86.3 7
5.25 o
12
88.5
3.44
10
• 89.5 x « 89.8
••5.54 o - 3.27
•23 n • 45
90.2
4.4
25
NO "
70 ••
60
y * 89.9 + 0.0028x
2 STROKE +
4 STROKE D
100
200
300
400
500
600
700
800
900
1000 MOO 1200 1300
DISPLACEMENT, cc
FIGURE 4-7
F-50 SOUND LEVELS, STREET AND COMBINATION STREET/OFF-ROAD
'75 - '76 YR OF MFG MOTORCYCLES
-------
IKV
110-
100-
<
x»
J 90 -
UJ
UJ
o
2:
0
80
o
in
Lu
70
60
x - 87.25 7 - 94.7. "x • 93.8
o " 4.57 + a • 9.5 cr - 7.84
n • 4 n » 3 n « 16
[- x-" /-
i
•»-
• ^^^t**^
fi+
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>r ' s
+
+ .
,—
i
4-
+ ++
^r"
i
a 4-
4-
.
X
r
^>-*"
^^
t
y • 88.6 + 0.01
72x
2 STROKE +
4 STROKE D
•
j _i 1 1 1— —
0 100 200 300 400 500 600 700 800 900 1000 1100 1200
DISPLACEMENT, cc
FIGURE 4-8. F-50 SOUND LEVELS, OFF-ROAD (ONLY) '75 - '76 YR. OF MFG. MOTORCYCLES
-------
I
M
N)
120-
110-
« 100-
•o
^J
10
LU
1
00
t
in 80-
co
70-
60-
•
•
•
— •
1
1
•f
•• i
+
i
1
H 1
, ,
y »71.6
" a
— i 1 1
i
i
i
i
- O.OOlZx
i
2 STROKE +
4 STROKE n
0 ° D
Dl .-, D
1 D
1
1 1 ! 1 1 1 1 i 1
600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 4-9 35 mph SOUND LEVELS, STREET AND COMBINATION
STREET/OFF-ROAD '75-'76 YR. OF MFG. MOTORCYCLES
-------
CO
•o
Ul
a
•ss.
o
CO
ex
Lf>
U)
120-
»
"x - 79.8
a - 3.77
n « 4
*"« 77.4
o « 1.67
n « 5
* • 75.0
a - 2.29
n - 9
no-
100-
90-.
80--
70--
.60
0
X
o
n
74.7
2.21
10
T
100
4-
4-
y - 78.65 - 0.0044x
D
4-
4-
4-
2 STROKE 4-
4 STROKE n
B
4-
4-
200 300 400 500 600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 4-10 55 mph SOUND LEVELS, STREET AND COMBINATION STREET / OFF-ROAD '75 - '76 YR.
OF MFG. MOTORCYCLES
-------
(d) Sound levels (J-331a, F-76, F-77, F-50), by displacement and use
categories; in-service motorcycles, year of manufacture '69-'76, modified
exhaust system: Table C-7.
(e) Change in sound levels (J-331a, F-76, F-50), referred to original
equipment manufacture (OEM), associated with installation of aftermarket
exhaust systems and user modifications: Table C-10.
Detailed information on test procedures, test sites, vehicle iden-
tification, and aftermarket product identification, is provided in
Appendices A, B and C.
4.2 Test Site, Rider, and Vehicle Variables
Test Sites
Noise data obtained in the course of this study were obtained at
eleven different test sites:
LETTER
CODE LOCATION > _
AArgosy Ave., Huntington Beach, California
B Orange County Fair Grounds, California
C Daytona Beach, Florida
D Los Alamitos Naval Air Station, California
E Pomona, California
F Houston, Texas
G St. Petersburg, Florida
H Albany, Georgia
I Chapel Hill, North Carolina
J Suffolk, Virginia
K Ft. Belvoir, Virginia
Test sites B, D, E, H, and J comply fully with SAE J-331a Recommended
Practice in all respects; the other sites depart in varying degrees (but
were the best sites available in the respective local areas), particularly
in reference to the requirement for concrete or asphalt ground surfacing
between the vehicle path and the microphone. Descriptions and photographs
of the test sites are contained in Appendix B.
In moving vehicle tests, sound reaches the microphone by two paths;
the direct path, and a reflected path, as illustrated below:
Direct and reflected
sound paths.
^—-^ j^
SOURCE
4-14
-------
&
+10
I
»
i °
r
i
' -5
1-10
SOURCE GO FEET FROM MICROPHONE
SOURCE 50 KET FROM MICROPHONE
/KUtin KsroNH or
f l-WEISNTINEKUtrOiU
Calculated interference of
third-octave band noise for
a source height of one foot,
microphone height of four
feet, and a surface reflection
of 0.9. (From Reference 3)
100 1000
FREQUENCY • HERTZ
10000
This suggests that noise measurements taken over hard pavement
could be either higher or lower than measurements taken over turf or weeds,
depending on the spectral content of the source noise. The tabular and
graphical data presented in this report include noise measurements taken
at all of the test sites. To assess the impact of the non-conforming
test sites on the statistical summaries (as shown on the graphical pre-
sentations) , the statistics of Figure 3-1, J-331a vs. displacement were
re-computed with data from the non-conforming sites exluded. Results of
this comparison are as follows:
Displacement
50-99 cc
100-169 cc
170-349 cc
350-749 cc
750 cc and over
Data from test
sites A thru K
* = 78.0*
-------
The foregoing indicates that while site discrepancies could be very
important in determining compliance of a particular vehicle with a noise
standard, the effect of site discrepancies as encountered in test sites
A, C, F, G, I, and K do not materially affect the statistical summaries
of the motorcycle noise data base. Additional data on site variables are
presented in Appendix C, Table C-15.
Rider Variables
At test site C (Daytona Beach) each motorcycle was operated by the
owner of the vehicle; rider weight specifications of the J-331a procedure
were not observed. The Daytona tests (run concurrently with the Daytona
Beach 200 Nationals) were conducted primarily to obtain a sample showing
the range of vehicle types, and the types of user modifications, repre-
sentative of vehicles currently on the road.
At all of the other sites, the rider was within the 165-175 Ib.
specification. A different rider, properly trained and instructed, was
used at each site, but all bikes at a given site were tested by the same
rider, except for site B, where three riders were employed.
Vehicle Variables
Production variability data provided by the vehicle manufacturers
show that a three-sigma variation of 1.5 dB(A) is common. Samples taken
over a six-month period by one manufacturer have shown a total variation
range of up to 4 dB(A). The reason for the latter, which may be a seasonal
variation, has not been explained. This suggests that a 2 dB(A) allowance
between design and not-to-exceed levels is an absolute minimum, without
considering the need for a further allowance in the enforcement situation.
Combined Variables Effect
•
Factors known or suspected to affect measured sound levels include:
(a) Weather variables affecting sound propagation:
— sunny vs overcast sky
- wind velocity/gradient/direction
- temperature and temperature gradients
- barometric pressure
- humidity
4-16
-------
(b) Weather variables affecting engine sound power generation:
- barometric pressure
- temperature
- water vapor pressure
- dry barometric pressure
- dry air density
(c) Manufacturing/assembly/adjustment tolerances affecting engine sound
power generation:
- dimensional variations
- spark timing
- fuel/air mixture
- compression variations
(d) Operations variables:
- engine temperature
- entering RPM or speed (J-331a)
- rapidity of throttle opening (J-331a)
- entering start point (J-331a)
- choice of gear selection (J-331a)
- closing RPM (J-331a and F-76)
- closing point (F-76)
(e) Site variables (site assumed to be in compliance with SAE J331a
Recommended Practice):
- surface texture (affecting tire noise)
- porosity (affecting absorption coefficient)
(f) instrumentation variables:
- acoustical calibrator accuracy
- sound level meter ANSI Type (1 or 2)
- sound level meter crest factor
- speedometer accuracy (J-331a)
- tachometer steady-state accuracy (J-331a)
- tachometer dynamic lag (J-331a and F-76)
Much work has already been done in assessing the effect of many of
these variable?1'2/: however, many undefined areas still exist. Although
the evaluation of the effects of these variables was outside the scope of
the EPA study, quantitative data on the effect of tachometer accuracy/ RPM
control, and gear selection were obtained in the course of test procedure
development.
4-17
-------
In addition, in the process of acquiring the noise data base,
substantial information was collected on the effects of combined
variables. Sound level data comparisons between/among vehicles were
made in four groupings:
(a) Different vehicles of the same model tested at different sites;
(b) Different vehicles of the same model tested at the same site;
(c) The same vehicle tested at different sites; and
(d) The same vehicle tested at the same site.
The sound level variations (summarized in paragraph 4.3, detailed
in Appendix C, Table C-14) are smaller than might be expected, considering
the extensive range of variability factors. Vehicles of the same model
but known to be configured differently (e.g., to meet different standards
in different States) have not been included in the comparisons.
4.3 Data Base Statistical Summaries
Sound levels, year of manufacture '75-'76 motorcycles:
J-331a F-76
Displacement
50-99 cc
100-169 cc
170-349 cc
350-749 cc
750 cc and Over
Street*
x = 78.0
«-= 4.64
n = 15
x = 81.5
o- = 2.95
n = 10
x = 83.1
-------
Transfer function, F-76 to J-331a sound levels (least squares linear
regression line):
y = -2.48 + 0.0066x for street* motorcycles
y = -2.21 + 0.0012x for off-road motorcycles
y = F-76 level - J-331a level
x = displacement, cc
The F-76 method yields statistical levels 4.1 dB higher than the
J-331a method at a displacement of 1000 cc, reducing to 1.9 dB(A) lower
at 100 cc for the street machines, with a similar trend in the off-road
vehicles.
Constant speed 55 mph sound levels as a function of displacement
(least squares linear regression line), yr. of mfg. '75-'76 motorcycles:
y = 78.65 - 0.0044X
y = sound level, dB(A) at 50 ft.
x = displacement, cc
It is of interest to note that this is a downward sloping line
with displacement, with motorcycles in the 900-1200 cc range being sta-
tistically 3.9 dB quieter than motorcycles in the 100-250 cc range, in
the 55 mph operating mode.
Variability in sound level data (from Table C-14); combined effect
of site, rider and vehicle variables:
J-331a F-76 F-50
x = 0.91 x= 1.17 x= 1.21
r = 1.29 cr = 1.58 <^= 1.83
n = 87 n = 69 n = 85
•Includes combination street/off-road motorcycles
4-19
-------
Comparison of motorcycles with modified exhaust systems vs. stock
configurations; data from test site C (Daytona Beach) only:
J-331a Sound Levels, dB(A)
Motorcycles in Motorcycles with obviously
stock configuration modified exhaust systems
x = 84.4 x = 93.6
0- = 7.2 6^ = 5.2
n = 49 n = 27
The tests at Daytona Beach were timed to coincide with the Daytona
Beach 200 National motorcycle events, to permit sampling from a wide
range of motorcycle types on a random basis. Vehicles were obtained by
open invitation to riders visiting the race and show events; all vehicles
offered were tested, and are reflected in the above statistics.
4.4 Aftermarket Exhaust Systems
The EPA study included making contacts with leading motorcycle
organizations such as the Motorcycle Industry Council, the Motorcycle
Trades Association, the National Motorcycle Dealers Association and many
local organizations, to invite a large segment of the aftermarket manu-
facturers and distributors of replacement exhaust systems to participate
in the EPA study. Major meetings and product display shows at Las Vegas
and Daytona Beach were attended to explain the objectives of the study,
answer questions, obtain basic information about the aftermarket industry,
and to solicit active participation by aftermarket manufacturers in a
comprehensive test and evaluation program of aftermarket exhaust systems.
These meetings were attended by manufacturer representatives from all
parts of the United States, thereby giving broad exposure to the program.
Subsequently, formal contacts were made with selected aftermarket
manufacturers in the California area, at which time the individual factories
were toured, detailed discussions were held with officials in each company,
and each company was asked to cooperate in providing replacement exhaust
systems to be tested on a family of selected motorcycles.
4-20
-------
Companies listed below were contacted either by phone, at a display
booth in the aftermarket shows, or visited at their manufacturing facilities:
Action-4*
Alphabets West*
Bassani*
Bates Industries
Butte Industries
Custom Chrome
Cyclone
Dean Maro's Pipelyne
Discojet
Doug. Thorley Headers
Hooker Headers*
Jardine Headers*
J&R Expansion Chambers*
Kook's Custom Headers
MCM Manufacturing*
R.C. Engineering*
S&S Manufacturing*
Santee Industries*
Skyway*
Torque Engineering*
Triple-A Accessories*
Winning Performance Products
Aftermarket Exhaust System Testing Program
An important part of the EPA motorcycle noise study involved sound
testing of aftermarket exhaust systems. With the full cooperation and
participation of aftermarket exhaust system manufacturers, a comprehensive
noise test program was conducted on approximately 107 aftermarket exhaust
systems and/or variations. These units were tested on 16 different motor-
cycles representing the five major motorcycle manufacturers. The testing
involved conducting the SAE J-331a and F-76 acceleration tests, and the
.F-50 stationary test on each of the motorcycles equipped with stock (OEM)
exhaust systems, followed by testing with the applicable aftermarket
exhaust systems. In addition to testing with the applicable aftermarket
and stock exhaust systems, variations were tested such as removing inserts,
baffles, fiberglass, and in some cases removing the mufflers altogether, all
of which represent forms of modified motorcycles found in circulation.
The participating aftermarket exhaust system manufacturers included
Santee, Alphabets, Jardine, Hooker, Bassani, S&S, MCM, Yoshimura, Torque
Engineering, winning Performance Products, J&R, Dick's Cycle West, RJS,
Kerker, Tr abaca
•Toured facility
4-21
-------
I ibattjuggjil
UUUG
(*u"mf^"T "•*•"?"'• -
i
- !_
• CO*
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1™^mji V?
i,J,^ii^?tt/--ifKH. »
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. s* / ' Z/J ,
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,*j^»* ;^a
FIGURE 4-11 AFTERMARKET EXHAUST SYSTEMS TO BE TESTED
-------
•
f
— ^
^ (iH/nf 11
^v" v ^iVfeH--^ '^-^
m Lc',. f;SD^ -H^^v'ft3i J;
"^ ! r^
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N-«S*a. *iC— ^M^M.1?^ ^i
\
tfa .f. t,.
-«. •».•
~«_ • •
» //
H
\
FIGURE 4-12 AFTERMARKET EXHAUST SYSTEM BEING INSTALLED FOR TEST
-------
and R. C. Engineering. Figure 4-11 shows some of the exhaust systems
laid out at the test site prior to installation and test. Figure 4-12
shows actual installations in progress.
Information on test procedures employed, the test site, and vehicle
and aftermarket product identification is provided in the Appendices.
Af termarket Product Study Results
Detailed sound level data on aftermarket and modified exhaust
systems are contained in Appendix C, and organized as follows:
(a) Listing of motorcycles used in the aftermarket product study;
Table C-8.
(b) Listing of aftermarket exhaust systems/components tested, correlated
with test vehicle employed; Table C-9.
(c) Sound level data for each configuration designed for the motor-
cycle on which tested (aftermarket manufacturer disguised); Table C-10.
A summarization of the test results follows.
Aftermarket Exhausfc systems as Configured by the Manufacturer
Sound Level Number of Configurations
Same as OEM 6
Quieter than OEM 9
1 dB higher than OEM 7
2 dB higher than OEM 6
3 dB higher than OEM 4
4-16 dB higher than OEM 50
Total configurations tested 82
Summary: 32 within 3 dB(A) of the OEM
50 4-16 dB(A) higher than the OEM
The above tabulation excludes configurations designated by the
manufacturers as "competition11 or "racer." Sound levels of configu-
rations so designated were as follows:
dB(A) re OEM
+14
+15
+ 9
+10
4-24
-------
Data on mufflers with competition or racer cores are included to
illustrate the increase in sound level that could be expected if a muffler
that has been specifically designed for competition usage is put on a
street bike or a combination street/off-road bike. Owners of street and
combination street/off-road motorcycles are known to modify their machines
with a competition-type exhaust system to obtain increased performance.
User Modifications
(a) Effect of removing the interchangeable baffles or inserts from
aftermarket mufflers:
dB(A) re OEM
+15
+21
+22
+29
+21
+15
+21
(b) Effect of removing the glass blanket from the removable insert
(insert replaced):
dB(A) re OEM
+ 4
(c) Effect of removing the OEM muffler:
dB(A) re Stock Config.
+22
+19
+16
+20
+19
+21
The sound levels resulting from removal of the muffler are
indicative of what could be expected if stock (OEM) or good quality after-
market exhaust systems are drastically modified. Removing inserts from
aftermarket mufflers (which is a very simple operation on some makes) has
an effect similar to removal of the entire muffler, without changing the
outward appearance of the motorcycle.
4-25
-------
Performance vs. Noise
To illustrate the effect on performance and the effect on
sound levels of aftermarket exhaust systems available for some of the more
popular motorcycles, a comparison is shown in Table 4-1 of exhaust systems
for the Honda CB750. Both performance and sound level data were acquired
on a variety of systems, including the original equipment. The maximum
horsepower and peak torque performance data on this particular motorcycle
were obtained on a dynamometer, whereas the sound measurements were obtained
using the J-331a vehicle acceleration type test procedure. It is apparent
from the data that the aftermarket exhaust systems designed to increase per-
formance over the original equipment also significantly increase the sound
level. Conversely, the quieter aftermarket exhaust systems that approach
the sound levels produced by the OEM system, have a somewhat adverse effect
on vehicle horsepower although the peak torque is somewhat enhanced. It
has been pointed out by some manufacturers that the effect of peak torque
occurring at a lower RPM than the OEM unit gives the feel of greater
"pulling" power, therefore leading to the conclusion that a particular ex-
haust system has improved the motorcycle performance.
Another important point illustrated in Table 4-1 is the availability
of different inserts or cores with the same baseline muffler. Several
manufacturers offer exhaust systems with a variety of removable cores or
adjustable vanes that can be added or decreased in number to obtain the
desired end-result in performance and sound level. This type of product
is offered for motorcyclists who have combination street/off-road bikes
which are used for competitive events or off-road activities in which
increased performance is important. The adjustable-vane type mufflers
have been designed to accommodate a range of motorcycles. Manufacturers
state that they purposely provide mufflers with two inserts: one for use
in an off-road situation, which will increase performance significantly,
but as a by-product will also increase the noise level, and a second insert
which is to be used by the motorcyclist when he is to ride that motorcycle
on the street. With a simple change, the motorcyclist can remove the
noisier hign performance insert and replace it with the street-legal type
insert which will comply with existing sound limits.
4-26
-------
TABLE 4-1
COMPARISON OF AFTERMARKET EXHAUST SYSTEMS FOR HONDA CB750
SOUND LEVEL AND PERFORMANCE
EXHAUST SYSTEM
HONDA 750 (OEM)
BASSANI (RACING) 4:1
BASSANI SMALL 4:1
RJS QUIET CORE
RJS STOCK CORE
DICK'S CYCLE WEST
TRABACA 2:1
J&R WITH STREET CORE
J&R WITH COMPETITION CORE
HOOKER 4:1
TORQUE ENGINEERING
JARDINE
R.C. ENGINEERING
ALPHABETS
WINNING
SOUND LEVEL (dBA)
(J331A)
81 dBA
91
81
82
87
82
89
84
91
89
83
82
87
83.5
88
MAX. H.P.
57.67 @ 8500 RPM
55.28 @ 8000
56.89 @ 8500
47.52 0 7500
56.0 (? 8000
60.3 @ 8500
57.92 0 8500
56.75 P 8000
53.6 0 8000
55.6 @ 8500
56.6 @ 8500
59.38 9 8500
Peak Torque
|
36.25 @ 8000 RPM;
36.12 9 7000
37.00 G 6500
35.25 Q 6500
37.06 9 6500
39.25 @ 6500
38.62 @ 6500
37.93 9 6500
37.00 @ 6500
35.75 9 7500
38.43 0 6500
37.68 @ 7500
SOURCE: Street Bike - July 1976,
"Honda 750 Header Shoot-Out." Jeff Peck
4-27
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4.5 Sound Levels at the Operator and Passenger's Ear Position
In order to assess potential benefits in hearing risk to
motorcycle operators from reducing motorcycle noise emissions, EPA con-
ducted a study of motorcycle sound levels at the operator and passenger
ear positions. The details of the study program are described in
Appendix E. Measurements were made on three large motorcycle models
(Honda 750, BMW, Barley-Davidson) in various operating modes. Measure-
ments were made with the motorcycle stationary, on a dynometer and under
moving conditions. In addition, measurements were irade with bare head,
head covered with a cap to reduce wind effects, and inside a helmet.
An attempt was made to distinguish wind turbulence and motorcycle (only)
contributions.
The information presented in the Appendix shows that wind-
induced noise (turbulence caused by wind flowing by the ear)is an
extremely complex phenomenon. It depends not only on wind speed but
vehicle and operator geometry and head attitude. In addition, it appears
that operator-induced turbulence increases passenger exposure. The
influence of helmets on operator exposure is another extremely complex
phenomenon, again depending on geometery and attitude. Both enhancement
and attenuation of sound levels compared to bare head levels were noted
in different frequency bands and for different head attitudes. It appears
that helmet-induced turbulence may increase operator sound exposure for
some helmet geometries.
At this time, motorcycle (alone) sound level (absent wind and
helmet effects) appears to be- the best measure for assessing motorcycle
operator noise impact. Both dynamometer and moving runs indicated that
the operator sound levels under F-76a acceleration conditions were about
100 dB(A) for the motorcycles tested (J-331a valves (50 feet)—Honda:
81 dB(A), BMW: 81 dB(A), Har ley-David son: 84 dB(A)). Wind noise was
below 90 dB(A) for all speeds up to 45 mph except for the trailing ear
when a motorcyclist without a helmet inclined his head 45 degrees away
from the line of travel. It can be concluded that under rapid acceleration
'conditions, for the motorcycles tested, motorcycle (alone) contributions
would outweigh wind noise for a helmeted operator.
The extent to which operator ear sound levels would decline as
fifty-foot sound levels declined in response to wayside regulations cannot
be confidently predicted. However, since attention must be given to in-
take and mechanical noise (both nearer the operator's ear than the exhaust
noise source), some reduction is to be expected.
4-28
-------
REFERENCES
1. Hillguist, R. K. and Bettis, R. A., Measurement of Automotive Pass-by
Noise, paper presented at the SAE Automotive Engineering Congress,
Detroit, Michigan, January 10-14, 1972.
2. Hemdal, John F., et al., A Study of Repeatability at Motor Vehicle
Noise Measurement Sites, Environmental Research Institute of Michigan,
1974.
4-29
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SECTION 5
PUBLIC HEALTH AND WELFARE ANALYSIS
-------
Section 5
PUBLIC HEALTH AND WELFARE ANALYSIS
The benefits to the public health and welfare which are expected
to occur as a result of establishing noise emission limits on motorcycles
are presented in this section. No significant adverse environmental
impacts are foreseen.
Because of inherent differences in individual responses to noise,
the wide range of traffic situations and environments, and the complexity
of the associated noise fields, it is not possible to examine all traffic
situations precisely. Hence, in this predictive analysis, certain stated
assumptions have been made to approximate typical or average situations.
The approach taken to determine the benefits associated with the noise regu-
lation is, therefore, statistical in that an effort is made to determine
the relative numbers of people that may be affected for each regulatory
option. It was necessary to make various assumptions in this analysis;
therefore, some uncertainties with respect to individual cases and absolute
numbers will remain.
People are exposed to motorcycle noise in a variety of situations.
Some examples are:
(1) Inside a home or office.
(2) Around the home (outside).
(3) In recreational areas.
(4) As a motorcycle operator or passenger.
(5) As a pedestrian or in transit in other vehicles.
Reducing noise emitted by motorcycles may produce the following
benefits:
(1) Reduction in average traffic noise and associated cumulative long
term impact upon the exposed population.
(2) Reduction in activity interruption from individual (single-event)
acceleration noise, and associated impact on the exposed population.
(3) Reduction in sound levels at operator or passenger positions which
may result in reduced hearing risk.
5-1
-------
The phrase "health and welfare" in this analysis and in the
context of the Noise Control Act is a broad term which includes personal
comfort and well-being, and absence of mental anguish, disturbances and
annoyance as well as the absence of clinical symptoms such as hearing
decrement or demonstrable physiological injury.
Dose respose relationships for noise induced hearing loss have
been fairly well documented. The non-auditory effects of exposure to
noise are less well understood. A number of stress reactions have been
observed to occur which result from a generalized syndrome caused by
the "flight or fight" reaction. Other physiological effects, such as
cardiovascular disease, increased susceptability to viral infection,
birth defects, and even cancer are suspected to have some relation to
the synergistic effects of noise exposure.
Annoyance due to noise is generally a manifestation of stress.
This stress reaction occurs when exposure to noise is experienced as an
unwanted intrusion on various activities, such as during sleep, speech
communication, or various types of relaxation. Such annoyance often
occurs after exposure to noise of very short duration.
Predictions of motorcycle noise emissions under various regu-
latory levels (referred to as study levels) are presented in Section
5.2 in terms of the sound levels which are associated with motorcycle
operating nodes. These sound levels are weighted according to traffic
populations or mixes before averaging to determine overall traffic sound
levels in urban areas. Predicted reductions in average urban traffic
sound levels from current conditions are presented in Section 5.3 for
various regulatory options for new motorcycles, both with and without
noise emission regulations for other types of vehicles. Projections of
the population impacted as well as the relative reductions in impact from
current conditions are determined from these reductions in average traffic
sound levels.
The use of average traffic sound levels to describe motorcycle
noise impact is of value in only a limited sense, since such an analysis
does not adequately describe the individual disturbances produced by
sJnqle motorcycle passbys in various situations. Annoyance frequently
d; -nds on the activity and location of the individual exposed to such
n: - -?. Thus, an average sound level does not account for the disruptive
an annoying peak noise intrusions produced by a single motorcycle accel-
er<;tion. Therefore, in residential urban, suburban, and rural areas, in
those cases where motorcycle accelerations are not likely to be masked by
other"traffic noise, effects of current representative motorcycle accel-
eration sound levels and future regulated sound levels are evaluated as
single events in Sections 5.4 and 5.5. Speech and sleep interferences
are presented as indicators of activity interference and the associated
adverse impact of motorcycle noise.
5-2
-------
In Section 5.6, the benefits to be derived from lowering motor-
cycle sound levels in off-road environments are estimated in terms of
reductions in the area currently impacted by motorcycle noise. Reductions
in potential hearing damage (risk to motorcycle operators and passengers)
are discussed in Section 5.7.
The analyses below present both absolute numbers of people
impacted and impact events and relative reductions in impact from current
conditions. While absolute values of present or future impact may not be
known precisely, the relative reductions in impact—of primary interest
here—are known with much greater accuracy. For example, while it may
not be possible to completely characterize the extensiveness and severity
of the noise impact of current motorcycle operations, relative reductions
can be accurately calculated and used for comparing various regulatory
alternatives. In addition, the relative changes found to occur in the
measures used in this analysis may help indicate what equivalent changes
would occur in impact measures which are not used in this analysis but
whose absolute values may reflect more accurately the effects of motor-
cycle noise on people.
5.1 Current Street Motorcycle Sound Levels
A statistical representation of stock motorcycle sound levels,
based on the data in Appendix C, is presented in Figure 5-1. These
data are acceleration sound levels as measured by the SAE J-331a test
procedure. This procedure is representative of very rapid acceleration
from 30 m.p.h. (full-throttle, high engine speed). Acceleration sound
levels as measured by J-331a can be adjusted to account for more commonly
encountered acceleration modes (near full-throttle, moderately high
engine speed). As discussed in Section 3, sound levels as measured by
the proposed regulation test procedure are assumed to be statistically
equivalent to J-331a levels. Cruise sound levels are based on steady-
state operation at various constant speeds. The data in Figure 1 were
developed from noise measurements of 200 unmodified motorcycles which
were selected to be representative, by year of manufacture and type,
of the national population of motorcycles in-service licensed for street
use in 1975. Additional noise measurements, discussed in Appendix C,
of 160 newly manufactured (1975-1976) street and dual-purpose motorcycles
yielded sound levels which did not differ significantly from the dis-
tribution shown in Figure 5-1. Hence, Figure 5-1 is considered to be
applicable to motorcycles currently on the road as well as to present
day newly manufactured motorcycles.
According to a national survey (Ref. 6), at least 12 percent of
street motorcycles, 12 percent of dual-purpose motorcycles (treated in
this analysis as street motorcycles), and 26 percent of off-road motor-
cycles have modified exhaust systems. (In Los Angeles and San Francisco,
these percentages were higher, approximately 15, 13, and 47 percent
5-3
-------
Figure 5-1. Percent of Unmodified Street Motorcycles which Exceed Any Given Sound Level
60
10 20 30 40 50 60 70 80 90
99
PERCENT EXCEEDING SOUND LEVEL
Source: Appendix C
5-4
-------
figure 5-2. Sound Levels of Exhaust-Modified Motorcycles
110-
-------
for street, dual-purpose, and off-road, respectively.) In general,
modification of a motorcycle exhaust system significantly increases the
motorcycle's sound level. Although other types of modifications such
as intake, modification may also affect the sound level of a motorcycle,
exhaust system modifications are typically the most noticeable form of
motorcycle noise tampering.
In this analysis, statistics are developed using several dif-
ferent assumptions on the incidence of modified motorcycles. The current
incidence, unchanged by Federal regulation (12%), and two lower incidences
(7% and 3%) are modelled for street motorcycles to reflect the expected
reduction of exhaust modifications. No modifications (0%) is analyzed
for comparison purposes and to focus on the unmodified motorcycle popula-
tion. Eliminating motorcycle modifications entirely, however, is not
considered to be feasible with even the most vigorous commitment to noise
enforcement by Federal, state and local governments. Reduction of modi-
fied motorcycles to about half the current incidence (7% of the population)
is considered the biggest reduction achievable through a Federal regula-
tion alone. Reduction to about one-quarter of the current incidence (3%)
is considered to be the biggest reduction achievable from a combination
of Federal regulation and vigorous state and local enforcement programs.
Similar reductions (24%, 16%, 8%, 0%) are also modelled for off-road
motorcycles.
The sound levels of 21 known exhaust-modified (non-competition)
motorcycles are plotted in Figure 5-2. The best fit of a normal distribu-
tion to the data is indicated by the straight line. In comparison with
the J-331a test results for unmodified motorcycles shown in Figure 5-1,
it can be seen that the mean sound level for exhaust-modified motorcycles
is 12.6 dB(A) greater than that for unmodif:-:d motorcycles. The distri-
bution of sound levels also shows a greater ispersion, with a standard
deviation of 5.3 dB(A) as compared to 3.7 dB(A) for the unmodified
motorcycles. These results are confirmed by previous measurements of
both unmodified and exhaust-modified motorcycles. Additionally, test
data indicate that the 25-35 mph steady speed sound levels of exhaust-
modified motorcycles are 15.6 dB(A) higher than those of unmodified
motorcycles (mean values of 88.9 dB(A) versus 73.3 dB(A)). It is opa-
rent that modified motorcycles are typically much louder than unrr, ified
motorcycles under both steady speed and acceleration conditions.
Since increasing a sound level by 12 decibels increases the dis-
tance at which the sound can be heard by a factor of 4, and the area by
a factor of as much as 16 (assuming spherical spreading propagation
losses), it is apparent that motorcycles with" modified exhaust systems
contribute to the overall noise impact from motorcycles in much larger
proportion than their actual numbers would indicate.
5-6
-------
Based on data presented in Figure 5-1, it is assumed in this
analysis that 55-mph and 35-mph cruise sound levels for motorcycles are,
respectively, 5 and 10 dB(A) lower than current J-331a sound levels, and
have the same standard deviations.
The median sound levels and standard deviations which have been
assumed for current and near-future populations of in-use motorcycles
are presented in Table 5-1. Representative acceleration sound levels,
as used in the following analysis, are assumed to be 3 dB(A) less than
the measured J-331a test level (see Appendix G).
For a population of instantaneous sound levels observed at equally
spaced time intervals that has a normal (Gaussian) distribution, the
energy-average of the sound levels over time is given by
* 2
L = L + 0.115 (1)
eq 50
V
where L^Q is the median noise level and is the standard deviation. In
the traffic analysis below, it is assumed that the distribution of road-
side sound levels for each type of vehicle is approximated by a normal
(Gaussian) distribution and that there is a steady stream of closely
spaced vehicle passbys. This assumption permits calculation of the energy-
average of the sound levels from median sound levels in a manner similar
to the computation of L in Equation 1. That is:
eq
2
L = L + 0.115 (2)
a 50
where L is the energy-average of the sound levels, LSQ is the median
level, and is the standard deviation of the sound levels. As Equation
2 demonstrates, the energy-averaged sound level depends on both the median
level and the variability of these levels. The energy-averaged sound
levels which will be used in the following analysis are also indicated in
Table 5-1.
*L is the equivalent A-weighted sound level in decibels. This is
diicussed in more detail below.
1 Johnson, D. R. A note on the relationship between noise exposure and
noise probability distribution, NPL AERO Report Ai40 (May, 1969).
5-7
-------
Table 5-1: Median Sound Levels of Motorcycles In Use (dB(A))
(Currently and in the Near Future, if Unregulated)
Unmodified
Motorcycles
Designed for
Street Use
Exhaust-
Modified
Motorcycles
35 itph
Cruise
71.5
84.0
Full-Throttle
Acceleration
(J331a)
81.5
94.0
Representative
Acceleration
(J331a - 3 db)
78.5
91.0
Standard
Deviation
3.7
5.3
Energy-Averaged
Representat ive
Acceleration
80.0
94.2
5-8
-------
5.2 Effect of Noise Regulations on Motorcycle Sound Levels
Various regulatory options considered for street motorcycles are
presented in Table 5-2. Since an infinite variety of regulatory options
are possible it is necessary to focus on a manageable few for analysis
purposes. These options have been analyzed both for health and welfare
benefits and for cost and economic impact (see below). The options have
been chosen close enough together to permit accurate interpolation. The
Agency is not bound to select any of the specific options analyzed here
nor should any significance be given to the particular options chosen for
analysis.
To analyze the effect of a motorcycle noise emission regulation,
sane assumptions must be made as to the changes which would occur in
the sound levels presented in Figures 5-1 and 5-2, due to a particular
regulatory standard. It is expected that in order to comply with a
Federal noise regulation manufacturers will produce motorcycles with
average sound levels about 2.0 dB(A) lower than the regulatory limit
to account for production and testing variabilities (see Chapter 6).
This production level may be assumed to be the mean of what is actually
a distribution of sound levels for the redesigned motorcycles.
Assuming that manufacturers will not quiet motorcycles which
already meet noise standards, and incorporating a production level of
2 dB(A) below the regulatory limit, the' distribution of future production
motorcycle sound levels are estimated in Figure 5-3 according to various
regulatory options.
As the distribution of new motorcycle acceleration sound levels
is changed with the implementation of noise emission regulations, the
population-average acceleration sound level will be reduced over time as
more and more old, unregulated motorcycles are replaced by new regulated
ones. For example, suppose a regulation were promulgated which provided
that no new motorcycle for street-use could exceed 80 dB(A), according
to the J-331a test procedure. The motorcycles above this sound level,
which comprise the "loudest" 66 percent of the unmodified street-use
motorcycles shown in Figure 5-3, would eventually disappear as quieter
motorcycles replaced older models. Eventually a new distribution would
be formed in which no unmodified street-use motorcycle would exceed the
80 dB(A) standard as measured by the J-331a test.
Acceleration sound levels do not correlate well with cruise sound
levels at 55 and 35 mph. A motorcycle which may be quieter than average
according to an acceleration test may be louder than average under cruise
conditions. This is due to the fact that mechanical noise, chain noise,
etc., can contribute significantly to a cruise sound level, since the
exhaust noise is generally lower than during acceleration.
5-9
-------
Table 5-2: Regulatory Options Analyzed for Street Motorcycles
Option Effective Date*
1979 1981 1984 1988
1
2
3
4 83 80 78 75
Not-to-exceed Sound Levels (dB(A)) as measured by F-76a procedure.
Production levels are assumed to be 2 dB(A) lower than these regu-
latory levels/ as discussed in the text.
*Accelerated lead times, with effective dates *of 1979, 1980, 1982,
and 1985, and more extended lead times, with effective dates of
1979, 1982, 1986, 1991 have also been analyzed for the 4 regulatory
options listed above.
83
83
83
83
-
80
80
80
-
-
78
78
5-10
-------
Figure 5-3. Statistical Distributions of Acceleration Sound Levels of Street Motorcycles
100-
95-
•v
80-
83dB(A)'
75-
80dB(A)
78 d8(A)
70-
•STUDY LEVELS
75dB(A)
10 20 30 40 50 60 70 80
PERCENT EXCEEDING SOUND LEVEL
90
99
NOTE: ASSUMES VARIOUS REGULATORY STUDY LEVEL LIMITS
PRODUCTION LEVEX IS 2 dB(A) BELOW REGULATORY LIMIT
5-11
-------
Since quieting a motorcycle to meet a sound level standard based
on an acceleration test may not result in a proportional decrease in cruise
sound levels, for the purposes of this analysis cruise sound levels will
be assumed to remain unchanged by noise emission regulations, with the
exception that cruise sound levels cannot exceed the acceleration sound
level. This assumption, which understates the benefits of any sound
reduction due to regulation, does not materially affect the analysis since
acceleration is the principal operational mode of interest.
5.3 Description of Traffic Noise Impact
In order to identify the circumstances in which street motorcycles
cause significant noise impact, it is necessary to relate motorcycle sound
level distributions to the sound level distributions for other traffic
vehicles.
Based on the data contained in Appendix C and orence 29,
Figures 5-4 and 5-5 illustrate the present statistics '. stributions of
sound levels of the various traffic vehicles, in both jeleration and
cruise situations, respectively. These figures illusi '^e that noise from
unmodified motorcycles does not stand out in traffic c! :dnated by trucks
with current sound levels (but does stand out in autom -bile-dominated
traffic), whereas exhaust-modified motorcycles are noisier than all other
vehicles under all operating conditions.
By 1982 heavy and medium trucks will be required to meet a
regulatory limit of 80 dB(A), as measured by the J336b test procedure.
Figures 5-6 and 5-7 show the truck sound level distributions for this
time period, based on the same sort of assumptions used in constructing
Figure 5-4 for regulated motorcycles. The J336b distribution is flat
at a level of 3 dB(A)* below the regulatory limit, and unchanged for
the population of trucks below this level. The cruise distributions
are unchanged except they cannot exceed the acceleration sound levels.
When the sound level distributions for the present population of
motorcycles are included in Figures 5-6 and 5-7, it can be seen that not
only will modified motorcycles continue to be the noisiest vehicles under
all conditions, but that a significant fraction of unmodified motorcycles
will be louder than trucks under the conditions of interest. Selected
study sound levels of various vehicles are shown in Figures 5-6 and 5-7
and it can be seen that a study regulatory level of 80 dB(A) or lower is
required to "submerge" motorcycle noise into overall traffic noise.
*Allows for production level 2 dB(A) below regulatory level, and typical
acceleration level 1 dB(A) below maximum acceleration test level.
5-12
-------
Figure 5-4. Distributions of Current Vehicular Sound Levels Under Acceleration Conditions
100
10 20 30 40 50 60 70 80 90
PERCENT EXCEEDING GIVEN SOUND LEVELS
Source: See Text
5-13
-------
Figure'5-5. Distributions of Current Vehicular Sound Levels al 27-3'J mph Steady Speeds
100
C5
10 20 30 40 50 60 70 80 90
99
PERCENT EXCEEDING GIVEN SOUND LEVELS
(Source: See Text)
5-14
-------
Figure 5-6. Estimated Future Sound Level Distributions for Transportation Vehicles Under
Acceleration Conditions
80dB A) TRUCK REGULATION
10 20 30 40 50 60 70 80 90
PERCENT EXCEEDING GIVEN SOUND LEVEL
NOTE: ASSUMES VARIOUS REGULATORY STUDY LEVELS
Source: See Text
5-15
-------
Figure 5-7. Estimated Future Sound Level Distributions for Traffic Vehicles Under 35 mph
Cruise Conditions
TOO
<
03
UJ
Ul
u.
o
in
u.
O
UJ
u
1
V)
5
Ul
u
Ul
cc
Ul
UL
Ul
CC
Ul
Ul
V)
95
90
10 20 30 40 50 60 70 80 90
PERCENT EXCEEDING GIVEN SOUND LEVEL
NOTE: ASSUMES VARIOUS REGULATORY STUDY LEVELS
Source: See Text
5-16
99
-------
5.3.1 Method for Calculating Traffic Noise Impact
Data for current and projected future street motorcycle sound
levels are summarized in Table 5-3. The operation-averaged sound levels
were obtained by weighing the acceleration and cruise sound levels ac-
cording to the time spent in each operational mode (assumed to be, when
constrained by traffic, 20% and 80% respectively). Using the same
assumption, the operation-averaged sound levels were obtained for other
traffic vehicles, and are shown in Table 5-4.
These operation-averaged sound levels are combined in the next
step to form the energy-average traffic sound level. This level is
computed by weighting the operation-averaged level produced by each type
of vehicle according to its relative frequency in a typical traffic mix
(indicated in Table 5-4).
Projections of reductions in average traffic sound levels due to
noise emission regulations are presented for urban street traffic where
the average vehicle speed is assumed to be 30 mph. Additional benefits
may accrue on highways where the average vehicle speed is assumed to be
55 mph. Note, however, that the benefits derived from the regulatory
schedules for new motorcycles considered here will be less for highway
traffic than for urban street traffic for several reasons:
o The number of people exposed to highway traffic noise is less
than the number of people exposed to urban street traffic noise (Ref. 29).
o The reductions in traffic noise emissions resulting from new
motorcycle regualtion will be less in freeway traffic than in urban
street traffic.
o Only a small proportion of motorcycle miles occur on freeways and
highways (Refs. 6 and 9).
As predicted in Figure 5-8, the number of people exposed to high-
way traffic noise is much smaller than the number of people exposed to
urban street traffic noise. According to References 6 and 9, only a very
small fraction of motorcycle miles occur on highways. For these reasons,
only urban street traffic situations are included in this analysis.
To perform the final step in determining the impact of motorcycles
in traffic, a noise measure must be utilized which condenses the informa-
tion contained in a given noise environment into a simple indicator of the
quantity and quality of noise, and which is a good descriptor of the over-
all long-term effects of noise on the public health and welfare. EPA has
chosen the equivalent A-weighted sound level in decibels, L , as its
general measure for environmental noise (Ref. 13). L is defined as:
5-17
-------
Table 5-3: Sound Levels for Street Motorcycles (dB(A))
Acceleration 35-mph Cruise
I
Statistical Standard
Median Value Deviation
Exhaust-modified
Motorcycles 91 5.3
Unmodified
Motorcycles
Current 78.5 3.7
83 dB(A) Study Level* — —
80 dB(A) Study Level — —
78 dB(A) Study Level — —
75 dB(A) Study Level — —
Energy-Average Statistical
Level Median Value
94.23 84
80.07 71.5
77.06 —
74.84 —
72.92 —
70
Standard Energy-Average
Deviation Level
5.3 87.23
3.7 73.07
73.07
72.82
72.44
70
Operation-Averaged
Equivalent Level
89.79
75.63
74.21
73.31
72.54
70
*Regulatory Level - Production Level is assumed to be 2 dB(A) lower.
-------
Table 5-4: Operation-Averaged Sound Levels for Non-Motorcycle Vehicles (dB(A)
Type of Vehicle
Urban Street
dB(A)'
Percent of
Traffic Volume
(Refs. 11, 27)
Heavy Trucks (Ref. 29)
(a) Unregulated
(b) 80 dB(A) Regulatory Level
(c) 75 dB(A) Regulatory Level
Medium Trucks (Ref. 29)
(including buses)
(a) Unregulated
(b) 80 dB(A) Regulatory Level
(c) 75 dB(A) Regulatory Level
Automobiles (Ref. 29)
(a) Unregulated
(b) Assumed Regulation
Motorcycles:
50
85.0
74.6
70.8
77.0
74.6
70.8
65.0
61.0
3.7
2.0
2.0
3.7
2.0
2.0
3.7
2.0
86.6
75.1
71.3
78.6
75.1
71.3
66.6
61.5
1.3
5.9
See Table 5-4
91.1
1.7
5-19
-------
Figure 5-8. Lsiimaled Number of People in Rt.-sidi.-ini.il Areas Currently Subjected to
Traffic Noise Above L^,, liti
-------
10 log
eq
10
t - t
2 1
2
P (t)
.dt
(3)
where t2 - t, is the interval of time over which the levels are evaluated,
P(t) is the time-varying magnitude of the sound pressure, and Pn is a
reference pressure standardized at 20 micropascals. When expressed in
terms of A-weighted sound level L., the equivalent A-weighted sound level,
L , is defined as:
eq
t
L = 10 log
eq 10
t - t
2 1
/.
10
.dt
(4)
In describing the impact of noise on people, a measure termed the
day-night average sound level (L, ) is used. This is a 24-hour measure
with a weighting applied to nighttime sound levels to account for the
increased sensitivity of people to intruding noise associated with the
decrease in background noise levels at night. Specifically, L, is de-
fined as the equivalent noise level during a 24-hour period, wi?h a 10 dB
weighing applied to the equivalent level during the nighttime hours of
10 p.m. to 7 a.m. This may be expressed by the following equation:
dn
10 log II 15
10 24 f
L /10
d
10 +
(L +10)/10 "7
n
10
j
(5)
where Ld is the "daytime" equivalent* level obtained between 7 a.m. and
10 p.m., and Ln is the "nighttime" equivalent level obtained between
10 p.m. and 7 a.m.
In order to assess the impact of traffic noise, a relation
between the changes in traffic noise and the responses of the people ex-
posed to the noise is needed. Responses may vary depending upon previous
exposure, age, socio-economic status, political cohesiveness, and other
social variables. In general, however, for residential locations, the
average response of groups of people is related to cumulative noise
exposure as expressed in a measure such as L, (Ref. 12). For example,
5-21
-------
the different effects of noise such as hearing damage, speech, other
activity interference, and annoyance were related to L or L, in
the EPA Levels Document (Ref. 12). For the purposes of^this analysis,
criteria based on L, as presented in the EPA Levels Document are used.
Furthermore, it is assumed that if the outdoor level meets L^n ^ 55 dB,
(identified in the EPA Levels Document as the level requisite to protect
the public health and welfare with an adequate margin of safety), no
adverse impact in terms of general annoyance and community response exists.
The community reaction and annoyance data contained in Appendix
D of the EPA Levels Document (Ref. II) show that the expected reaction
to an identifiable source of intruding noise changes from "none" to
"vigorous" when the day-night noise level increases from 5 dB below
the level existing without the presence of the intruding noise to 19.5
dB above the level before intrusion (Ref. II). Thus, 20 dB (L^ =55 to
75 dB) is a reasonable value to associate with a change from 0 to 100
percent impact. Such a change in level would increase the percentage of
the population which is highly annoyed to 40 percent of the total exposed
population (Ref. 12). Furthermore, the data in the Levels Document sug-
gest that within these upper and lower bounds the relationship between
impact and level varies linearly, that is, a 5 dB excess (L = 60 dB)
constitutes a 25 percent iirpact, and a 10 dB excess (L * = 63 dB) consti-
tutes a 50 percent impact.
For convenience of calculation, percentages of impact may be
expressed as fractional impact (FI). The fractional impact method explic-
itly accounts for both the extent and severity of impact. An FI of 1.0
represents an impact of 100 percent, in accordance with the following
formula:
f 0.(
(°
.05 (L-55) for L > 55
FI = ^ (6)
for L < 55
where L is the observed or measured L^n for the environmental noise. Note
that FI can exceed unity for exposures greater than L^ = 75.
The ijipact of traffic noise may be described in terms of both
extensiveness (i.e., the number of people impacted) and intensiveness
(i.e., severity of impact). The fractional impact method explicitly
accounts for both the extent and severity of impact.
The magnitude of the impact associated with a given level of traffic
noise (LJn) may be assessed by multiplying the number of people exposed to
that level of traffic noise by the fractional impact associated with this
level as follows:
•
ENI = (FI ) P (7)
i i
5-22
-------
where ENI , the equivalent noise impact, is the magnitude of the impact
on the population exposed to traffic noise L* , and is numerically equal
to the number of people who would all have a fractional impact equal to
unity (100 percent inpacted). Fli is the fractional impact associated
with an equivalent traffic noise level of I^n and P± is the population
exposed to this level of traffic noise. To illustrate this concept, if
there are 1000 people living in an area where the noise level exceeds the
criterion level by 5 dB (and thus are considered to be 25 percent impacted,
FI = 0.25), the environmental noise impact for this group is the same as
for 250 people who are 100 percent impacted (1000 x 25% = 250 x 100%).
When assessing the total impact associated with traffic noise, the
observed levels of noise decrease as the distance between the source and
receiver increase. The magnitude of the total impact may be computed by
determining the partial impact at each level and summing the over each of
the levels. The total impact is given in terms of the equivalent number
of people impacted by the following formula:
ENI =Z P . FI (8)
i i i
where FIi is the fractional impact associated with I^n and P^ is the popu-
lation associated with L^n. In this study, the mid-level of each 5 dB
sector of levels above Ldn = 55 dB is used for Ldn in computing ENI.
The change in impact associated with regulations for noise
emissions of traffic vehicles may be assessed by comparing the magnitude
of the impacts both with and without regulations. One useful measure is
the percent reduction in impact, which is calculated from the following
expression:
ENI (before) - ENI (after)
Percent Reduction in Impact = 100 (9)
ENI (before)
The population figures (P.) in Eq (7) for urban street traffic are
based on a survey in which the total population exposed to outdoor noises
of Ld above 55 dB was estimated from measurements taken at 100 sites
throughout the United States (Ref. 14). The sites were selected far enough
from freeway traffic and airports that these sources of noise were not
significant contributors to the measured outdoor noise levels. Urban
street traffic was a dominant source of noise for each of the survey sites.
The results from this study are presented in Table 5-5.
Using the data contained in Table 5-5, an ENI for existing traffic
conditions (with trucks not regulated) of 34.6 million is calculated as
shown in Table 5-6.
5-23
-------
The ENI values associated with reductions in average urban street
traffic noise levels are predicted by shifting (reducing) the values of
Lj in Table 5-5 by a specified reduction in traffic noise and performing
conputations similar to those shown in Table 5-6. In following this pro-
cedure for estimating ENI, it is assumed that: (1) reductions in urban
street traffic sound levels produce equal reductions in the L^ for the
outdoor noise, and (2) the population in urban areas will remain constant.
The latter assumption is made for convenience only. It does not affect
the relative effectiveness of the study regulation schedules. If popu-
lation increases in urban areas are more or less evenly distributed, only
the absolute number of people impacted will be different from the
estimates; the relative reductions will remain unchanged. The actual
numbers can be approximated by multiplying the ENI estimated for a given
year by the fractional population increase expected to occur in that year.
5,3.2 Reduction in Traffic Noise Impact
The reduction in average urban traffic noise expected as a result
of motorcycle noise emission regulations is summarized in Table 5-7. Note
that if noise emission regulations are applied to other vehicles such as
trucks, there will already be an initial reduction in traffic noise,the
extent of which is dependent on the stringency of the regulation, the date
of its implementation, and the turnover rate for the vehicle population
involved. Therefore, two different baseline cases are examined: an 80
dB regulatory limit for new trucks only; and regulatory limits for all
vehicles, including a 75 dB regulatory limit for new trucks.
These computations were performed using both normal and accelerated
regulatory lead times (shown in Table 5-2). The difference in ENI for the
two cases was insignificant, however, since the lead time differences are
relatively small and the motorcycle population replacement rate is rela-
tively high.
Since motorcycles comprise only 1.7% of the typical urban traffic
stream, reductions in motorcycle sound levels will not result in large
reductions in overall traffic sound levels (indicated in Table 5-7). It
is apparent from Figure 5-9 that even with a 10 dB reduction in motorcycle
sound levels, the impact of current traffic noise (assuming trucks are
regulated) is reduced by less than 5 additional percentage points. Reducing
the percentage of exhaust modified motorcycles results in a greater improve-
ment, over 15 additional percentage points. Due to anticipated reductions
in sound levels of other vehicles, the impact of future traffic noise is
projected to be reduced by almost 60%.
The effect of motorcycle noise emission standards in this future
quieted environment are shown in Figure 5-10. Unregulated motorcycles will
be louder than any other traffic vehicle in this environment. Assuming
that modified motorcycles are reduced to 3%, a 78 dB(A) regulatory level
5-24
-------
Dislr
Table 5-5
ibulion of Urban Population ci or Greater Than a
Specified L ,
Ldn
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Cumulative
Number of People
(Millions)
134.0?
133.94
133.76
133.46,
132.99
132.34
131.46
130.37
129.04
127.53
125.87
124.09
122.19
120.15
117.98
115.64.
113.01
110.12
106.80
102.98
98.544
93.427
87.665
81.237
74.222
Ldn
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
Cumulative
Number of People
(Millions)
66.733
58.997
,51.234
43. 668
36.542
30.061
24.320
19.352
15.200
11.791
9.046
6.853
5.155
3.826
2.776
L963
1.347
0.889
0.559
.332
.787
.093
.039
,.012
.002
.0
Source: Ref. 14
5-25
-------
Table. 5-6
Calculation of Equivalent Number of People Jmpe.ctcd
By Urban Sfreel Traffic Noise
t1.
c!n
55
60
66
70
75
80
Populaiion Exposed
• * •
to L , or Higher P
dn c
(millions)
93.4
59.0
24.3
6.9
1.3
0.1
Population Exposed
to Levels Between
. i . . H- 1
L , and L ,
on dn
* i 1 *
p.-p'*V
1 C C
34.4
34.7
17.5
5.5
\.2
0.1
Fractional
Impact to
A'lid- Level
FI.
i
0.125
0.375
0.625
0.875
1.125
1 .375
Equivalent Number
of people impacted
FI. P.
i i
4.3
13.0
10.9
4.9
1.4
0.1
Total ENI= 34.6 M
Source: Ref. 29
5-26
-------
Table 5-7: Reduction of Urban Traffic Sound Level (dB(A) at 50 ft.)
Current Baseline Level, All Vehicles Unregulated; 72.26 dB(A)
With Trucks Regulated to 80 dB(A)
Motorcycle Fraction Modified Motorcycles
Regulatory
Study 12% 7% 3% 0%
Levels—dB (A)
Current
83
80
78
75
With Regulation
2.74
2.82
2.85
2.88
2.94
of All Other
3.15
3.23
3.27
3.31
3.57
Vehicles,
3.47
3.56
3.61
3.65
3.73
Including
3.74
3.84
3.90
3.94
4.02
True!
Motorcycle Fraction Modified Motorcycles
Regulatory
Study 12% 7% 3% 0%
Level—dB (A)
Current
83
80
78
75
5.53
5.67
5.74
5.79
5.91
6.78
6.99
7.10
7.17
7.37
7.03
7.25
7.36
7.44
7.64
7.67
7.94
8.07
8.17
8.41
5-27
-------
Figure f>-9. Relative Impact of Urhiin Traffic
(Current EMI; 34.5809)
CUR RENT IMPACT: 100%
NO IMPACT:
111
O
cc.
Ul
a.
h-"
O
<
CL.
1
2
ai
nc
cc
o
LL
o
2
o
1-
o
<
DC
u.
80%
G0%
40%
20%
0%
LEVEL OF
(IXHAUST
P^ODIFSCATIOWS
7%
30/
/O
0%
83 80 78
MOTORCYCLE REGULATORY STUDY LEVEL dB(A)
75
•ASSUMES SO dD(A) TRUCK REGULATORY LEVEL
(RESPONSIBLE FOR THE REDUCTION FROM 100%
IMPACT—CURRENT IMPACT—TO 76% IMPACT AT
83 dB(A) REGULATORY STUDY LEVEL)
5-28
-------
Figure 5-10. Relative Imp net of Urban Traffic Woke in Future Quieted
Environment* (Current ENI: 34.5809)
IMPACT IN
FUTURE QUIETED
ENVIRONMENT:**
(ENI: 14.2260)
100%
LU
O
cr.
UJ
a.
§
DC
cc
O
II.
O
O
<
cc
u.
80%
60%
40%
20%
NO IMPACT
0%
12% LEVEL OF
EXHAUST
MODIFICATIONS
7%
3%
0%
83
80
78
75
MOTORCYCLE REGULATORY STUDY LEVEL dB(A)
* ASSUMES ALL VEHICLES REGULATED (TRUCKS AT 75dB(A) REGULATORY LEVELS)
**NO FURTHER REDUCTION IN MOTORCYCLE NOISE EXCEPT REPLACEMENT
5-29
-------
for motorcycles will reduce the impact of future traffic by approximately
one-third. Table 5-8 shows the actual number of people exposed to various
levels of traffic noise. Although the percentage changes shown in Figure
5-9 are in some instances small, the actual numbers of people exposed may
be substantial. For example, with trucks regulated at the 80 dB(A) level,
76.05 million people will be exposed to traffic sound levels of L, 55
or greater. Reducing motorcycle noise from current levels to a regulatory
level of 78 dB(A) would reduce the number of people exposed to these
levels by almost one million. If modified motorcycles are limited to 3%
of the motorcycle population, traffic sound levels of L^n 55 or greater
would impact approximately five million fewer people (76.05 people cur-
rently exposed reduced to 70.70 people). The effect of a motorcycle
noise regulation in a future traffic environment (with all other vehicles
quieted) is, as seen in the second part of Table 5-8, even more dramatic.
5.4 Motorcycles as an Individual Noise Source
To this point, the analysis of motorcycle noise impact has focused
on the contribution of motorcycles to day-night average traffic sound
levels. The impact contributions which are calculated in this way are
somewhat generalized and do not necessarily represent specific impact
situations. For example, they do not reflect the fact that a great deal
of hourly acoustical energy contributed by motorcycles in a given area may
be generated in only a short period of noise during a few accelerations.
Yet these short, intrusive events may be the most annoying noise-related
situations faced over the entire day by a large number of residents
conversing or relaxing in and around their homes. In some situations
motorcycle noise will be a constituent of traffic noise, and the con-
clusions reached by using L^n will be essentially correct. In other
instances, however, the motorcycle will be operating in the presence of
only one or two other vehicles, and can be considered as a single source.
On some occasions motorcycle noise will be partially masked out
by other noise in the environment, and the conclusions reached using
Lgn will be essentially correct. At other times or situations one can
expect that other noise sources will not mask the noise of a passing
motorcycle, and thus the motorcycle will cause a finite impact. The
actual impact from motorcycles is certainly due to a combination of
various levels of motorcycle noise and other environmental noise.
It is difficult to derive a direct measure of the annoyance
attributable to the intrusiveness of motorcycle noise. Although numerous
surveys indicate that motorcycle noise is a major source of annoyance,
there are few scientific studies which have directly related motorcycle
sound levels to degrees of annoyance.
5-30
-------
Table 5-8: Cumulation Urban Population (millions) vs. Traffic Sound Level (dB(A) at 50 feet)*
With Trucks Regulated to 80 dB(A)
Motorcycle
Regulatory
Level
Current
83
80
78
75
Fraction
Modified
12%
3%
12%
3%
12%
3%
12%
3%
12%
3%
With All Vehicles Regulated,
Motorcycle
Regualtory
Level
Current
83
80
78
75
Fraction
Modified
12%
3%
12%
3%
12%
3%
12%
3%
12%
3%
55
76.05
70.70
75.48
70.03
75.27
69.66
75.06
69.36
74.64
68.76
Day-Night
60
38.39
33.50
37.82
' 32.91
37.61
32.59
37.40
32.33
36.97
31.81
Average Sound Level
65 70
12.68
10.50
12.40
10.25
12.30
10.12
12.20
10.01
12.00
9.79
3.05
2.39
2.97
2.32
2.93
2.28
2.90
2.09
.2.84
2.18
"*'
.39
.34
.37
.25
.36
.24
.36
.24
.35
.23
80
.01
.00
.00
.00
.00
.00
.00
.00
.00
.00
ENI
23.14
20.52
22.83
20.19
22.71
20.02
22.60
19.84
22.37
19.60
Including Trucks at 75 dB(A)
55
54.88
43.45
53.56
42.10
53.25
41.10
52.78
40.53
52.01
39.11
Day-Night
60
22.34
15.10
20.99
14.45
20.64
13.97
20.33
13.84
19.85
13.02
Average Sound Level
65 70
5.95
3.79
5.71
3.60
5.60
3.45
5.48
3.36
5.33
3.15
1.10
.55
1.04
.51
1.00
.48
.97
.50
.94
.41
75
.06
.01
.06
.01
.05
.01
.05
.01
.04
.01
80
.00
.00
.00
.00
.00
.00
.00
.00
.00
.00
ENI
14.22
10.29
13.65
9.91
13.31
9.62
13.31
9.48
13.04
9.04
*Por current baseline case, with no regulations, see Table 5-5.
5-31
-------
When queried in attitudinal surveys, respondents generally rate
motorcycle noise as a major, if not the major, source of annoyance from
noise. For example, the response to noise survey questionnaires mailed
to a random sample of individuals showed that the respondents rated motor-
cycles as the major noise "problem" while automobiles and trucks were
ranked second and third as noise problems with rankings of 67 percent and
62 percent respectively, relative to motorcycle noise at 100 percent
(Ref. 1). In another survey, respondents were asked to rate 25 noise
sources on a scale from "not bothering at all" to "extremely bothering".
Motorcycles were rated as "not bothering at all" by the smallest percen-
tage of people (32.2 percent) and were rated as "extremely bothering" by
the highest percentage of people (12.6 percent). A total of 44.8 percent
rated motorcycle noise as either "moderately", "highly", or "extremely"
bothering in their neighborhoods (Ref. 2).
In the same study, people rated traffic noise situations in terms
of both intensity and frequency of annoyance. People annoyed by motor-
cycle noise rated the intensity midway between "definitely annoying" and
^•strongly annoying". The only vehicle type receiving a higher annoyance
intensity rating was buses. In terms of frequency, motorcycles were
reported as the source of annoyance 23 percent of the time, second only
to automobiles with a 36 percent frequency of annoyance. People are
annoyed, it seems, by motorcycle noise greatly out of proportion to actual
numbers of motorcycles as compared to other types of traffic vehicles.
The most applicable investigation undertaken is one in-which
a sample of 57 persons rated vehicular noise at an open-air test track
as the vehicles were driven by at a distance of 7.5 meters at the closest
point (Ref. 20). Listeners were exposed to both constant speed cruises
and accelerations. Figure 5-11 shows the results of the subjective noise
rating of motorcycles as a function of A-weighted noise level as heard
by the listener. There was little difference in the ratings of 2-stroke
and 4-stroke motorcycles. Ratings ranged from "quiet" at 68.5 dB(A) to
"excessively noisy" at 96.5 dB(A). These results seem to compare fairly
well with those shown in Figure 5-11 for single noise events in which
ratings vary from "quiet" at 73 dB(A) to "noisy (strongly)" at 92 dB(A)
(Ref. 33).
5.5 Reduction of Single-Event Noise Impact
In this section, annoyance caused by motorcycle acceleration
noise is analyzed as a single event phenomenon (not part of a continuous
traffic stream) in rural, suburban, and residential urban areas. Impacts
in high density urban areas have been calculated but are not the focus of
this analysis, since motorcycle noise does not frequently occur as a
single-event impact in these situations. The previous traffic impact
analysis specifically accounts for health and welfare benefits in these
high-density urban areas. Potential impacts in high-density urban areas
(assuming no traffic masking) are included on page 5-51.
5-32
-------
Figure 5-11. Subjective Noiyj Rotincj of Motorcycle Sound Levels
— 9G.5dB(A)
70 80 90
SOUND LEVEL (dS(Aj)
SOURCE: REFERENCE 20
— 82.5 dD(A)
77.8riB(A)
— 68.5 cU
100
5-33
-------
Figure 5-12. Individual Judgements of Acceptability of Singlu Noisi: Events
NOISY
(STRONGLY) 6
e
P
< ACCEPTADLE
> (QUIET)
cs
<
I-
IU
VERS QUIET
(NOT HKARD
AT ALL)
100
A-WEIGHTED SOUND LEVEL IN dB(A)
SOURCE: REFERENCE 3
5-34
-------
Annoyance is a difficult reaction to measure. It may pass rapidly
and the actual cause may remain unnoticed, or it may add to other stimuli,
causing stress and leading to physiological problems (Ref. 13, 32). As
measured from people's responses to questionnaires on this subject (dis-
cussed in Section 5.4), however, there is no doubt that considerable
annoyance currently exists due to motorcycle noise.
It is clear that a loud vehicle acceleration may interrupt certain
activities such as conversation or sleeping. These interruptions may
again lead to annoyance, but can in themselves also represent a degrada-
tion of health and welfare. For instance, in a recent study of annoyance
caused by different levels of simulated aircraft noise for people seated
indoors watching television, annoyance was seen to be partially a result
of speech interference (Ref. 30). Not only is a television program or
another person speaking more difficult to hear during the time in which a
noisy vehicle is passing by, but it has been observed that the distraction
from a conversation in which a person is engaged may also cause annoyance.
A speaker may behaviorally attempt to cope with the noise intrusion either
by increasing his or her vocal effort, or in severe cases, by ceasing to
speak altogether until the intrusion subsides. Such behavioral reactions
may be quite indicative of general annoyance and disturbance with the
intrusive noise event. Similarly, the reaction to a noise intrusion
during sleep may in many cases be a change in sleep stage (from "deeper"
to "lighter" stage). If the intrusive noise is of sufficient duration or
intensity, awakening may result. In either case, repeated disturbance of
people's activities may be expected to adversely affect their well-being
(Bef. 13).
For these reasons it seems appropriate that the analysis examine_
the effects of noise on both speech communication and sleep in some detail,
in order to determine the direct effect motorcycle noise may have on these
activities, as well as to aid in an estimation of the total annoyance
attributable to motorcycle noise. These single-event noise intrusions
become particularly important in light of anticipated regulations and
efforts to reduce noise from other motpr vehicles and other urban noise
sources. Without a reduction in motorcycle noise, the motorcycle may very
well stand out as one of the most intrusive noise sources in the community.
5.5.1 Speech Interference
The interference of speech (i.e., -conversation) due to other noise
intrusion can occur when people are both indoors and outdoors. For pur-
poses of this analysis, it will be assumed that virtually all conversation
takes place during the daytime hours; thus, only "daytime" (7 a.m. to
10 p.m.) motorcycle operations will be considered to contribute to speech
disruption, whereas only "nighttime" operations will be considered to con-
tribute to the disruption of sleep. Data are not avaliable on the number
5-35
-------
of motorcycle miles occurring at night. In this analysis it is assumed
that tho vast majority of motorcycle mileage, 95% of the total, occurs
during non-sleeping hours. This assumption is a "best guess" and may
over-estimate the magnitude of speech interference and underestimate the
absolute magnitude of sleep disturbances. The relative benefits in each
case, however, is unaffected by this assumption.
Conversation can be disrupted by externally propagated motorcycle
noise both inside and outside the home. These two situations will be
examined separately. In the discussions that follow, "inside the home"
and "outside the home" should be taken to mean respectively "inside any
building" and "outside any building".
It is estimated that motorcycles travel a total of 19.7 million
miles daily on street and highway systems (Ref. 8). Since there are only
some 3 million miles of roads and highways in the United States, public
exposure to motorcycles is seen to be quite commonplace. However, there
is little information to indicate how motorcycle mileage is distributed
between the various land-use areas (high density urban, rural, etc.).
It is assumed in the following analysis that motorcycle miles
are apportioned among the various land-use areas in the same manner that
the population is distributed. Based on the population data in Ref. 28,
this distribution is shown in Table 5-9. This assumption does not account
for people living in suburban and rural areas who commute to urban areas.
A major portion of street motorcycle operations, however, consist of
recreational riding (Ref. 8). It seems reasonable that this kind of
operation would generally occur in suburban and rural areas, and would
therefore balance commutation to urban areas.
Since motorcycle acceleration sound levels are considerably
higher than cruise sound levels, it is important to determine the rela-
tive frequency of acceleration situations. The average number of stops
per mile for various types of road systems has been determined (Ref. 9),
and appear in Table 5-9 for each generalized type of road system. It is
assumed that such values are reasonably representative of the frequency
of motorcycle accelerations from complete stops. Although not presented
in Table 5-9, the percentages of time spent in various modes of operation
conform quite well with data obtained for passenger cars and trucks in
other studies (Ref. 9).
5-36
-------
Table 5-9. Motorcycle Mileage and Road Statistics
Fraction of
Total
Road Type Motorcycle Miles
Rural
Suburban
Urban
Residential
26%
49%
18%
Stops/Mile*
0.1
1.5
1.77
Acceleration Miles/Day
20,000
564,000
243,000
*Ref. 9
Based on 7.2 billion street motorcycle miles per year (Ref. 8)
Note: High density urban mileage and highway mileage are not included
in this single-event analysis.
5-37
-------
For the purposes of this analysis, a representative motorcycle
acceleration from a complete stop to 35 miles per hour, unconstrained
by traffic, is assumed to occur at an average rate of 0.3 g (5.3 seconds,
135 ft.), somewhat more rapid than for a typical automobile acceleration
(Ref. 9). For each acceleration from a stop, one passing acceleration of
the same sound level but one-half the distance is added. By multiplying
the number of motorcycle miles in each land use area by the number of
stops per mile and associated distances, "acceleration" miles are deter-
mined. These are also tabulated in Table 5-6.
To determine impact on speech and the reduction in speech
interference which would be achieved at different levels of motorcycle
quieting, the following method was utilized:
Step 1. Representative energy-averaged acceleration sound levels at 50
feet are computed for both modified and stock motorcycles. These
data were presented in Table 5-1.
Step 2. The distances from a typical motorcycle acceleration at which these
levels are decreased in steps of 5 dB are calculated (Figure 5-13).
These distances are taken to begin from the center of the roadway.
Step 3. The number of people living in 5 dB bands from the 50-foot accel-
eration level is calculated by multiplying the population density of
the land uses in which the motorcycles operate by the width of the
5 dB bands (calculated in Step 2) and then by the number of motor-
cycle acceleration miles within the given land uses. Depending on
land use, the first 50 to 90 feet (as indicated in Table 5-11) on
each side of the center line are assumed to be part of the roadway
and adjoining sidewalk, and thus assumed to contain no people.
Step 4. Speech impact is calculated for each of the 5 dB(A) bands. The
impact, expressed as a fraction, is derived from a curve relating
speech interference to equivalent sound level (Figure 5-17).
Step 5. The relative total impact is computed in each band by multiplying
the number of people living in each band (from Step 3) by the
associated fractional impact (from Step 4.).
This methodology is discussed in more detail, as follows:
Step 1 - Discussed above.
5-38
-------
Figure 5—13. Illustrative Example of Calculation of Distances Between Stops of 5 dB(A)
Attenuation from the 50 Foot Average Motorcyle Sound Level
ATTENUATION CURVE FOR
A GIVEN LAND USE
100
200
400
800
DISTANCE FROM SOURCE (FEET)
5-39
-------
Step 2 - For the purpose of analyzing motorcycle acceleration
noise in this section, each of the land use areas is assumed to have a
simplified mix of high-rise, low-rise, and open-spaced areas which cor-
respond to different propagation laws (Table 5-10). The computation of
the distance between each 5 dB(A) attenuation band-from the motorcycle
involves determining the sound attenuation characteristics typical of each
area. In low-rise areas, the sound propogates radially, and attenuation
is correspondingly greater. In urban high-rise areas the building density
may be so great that the noise rom a point source, such as a motorcycle,
located in the middle of an intersection, decays in the lateral direction
as if the vehicle were a line source: the acoustical waves have no chance
to dissipate in the direction parallel to the motorcycle's line of travel.
In addition to these two forms of laterally directed geometric spreading,
building, ground, and air absorption also contribute to attenuation. A
review of recent literature on urban sound propagation produced the atten-
uation values for traffic line sources shown in Figure 5-14. Applying the
same attenuation values to point source spreading losses yields the curves
of Figure 5-15. As a simplification, all low-rise areas are assumed to
have point source attenuation characteristics, and all high-rise areas are
assumed to have line source characteristics.
The attenuation of noise in rural areas also involves many factors
(Figure 5-16). The low density of buildings in rural areas allows us to
neglect building reflection and absorption, so the distance computations
are straightforward.
Step 3 - Once the 5 dB(A) band distances are known, the band width
area within each land use category may be calculated by multiplying the 5
dB(A) distances by the number of day time acceleration miles occuring in
each category (95% of the values shown in Table 5-9). The number of people
living within each band can then be found by multiplying the bandwidth area
by the average population density of the locale (the appropriate population
densities'are indicated in Table 5-11).
It is estimated that people spend an average of 13 daytime hours
inside each day (Ref. 31). That is, they spend approximately 87 percent
of the day inside. Taking this fraction of the number of people in each
band, the indoor speech impact may be determined. The outdoor speech
impact is similarly determined by taking 3 percent of the numbers calcu-
lated in step 3 (Ref. 31).. This corresponds to 0.4 hours, estimated to
be the time during which people are outdoors each day. It should be noted
that the time outdoors does not include pedestrians or people engaged in
other forms of transportation during the day. Rather it is intended to
include those time periods in which people are relaxing outdoors—either
outside a home, business or cultural institution.
5-40
-------
U1
03
•Q
Ut
Ul
O
O
u.
UJ
cc.
O
D
UJ
<
00
TJ
10
O
O
u.
6
in
oc
o
20
30 f-
40
.50 1 2345
DISTANCE F"OM SOURCE (HUNDRED FEET)
Figure 5-14. Attenuation of
Traffic Line
Sources, by
Urban Land
D
z
UJ
<
30
40
I I I
GEOMETRIC
SPREADING
(6dB(A)/dd'l
TOTAL
ATTENUATION
AIR ABSORBTION-
(2dB(A)/1000'l
GROUND ABSORBTION-
(1dB(A)/ddM
I
I
I 1
.5 1 2345 .5 1 2345
DISTANCE FROM SOURCE (HUNDRED FEET) DISTANCE FROM SOURCE (HUNDRED FEET)
*dd= DOUBLING OF DISTANCE
Figure 5-15. Predicted
Attenuation of
Point Sources,
by Urban Land
Use
Figure 5-16. Attenuation of
Point Source Noise
Levels Over Open
Terrain35
-------
Table 5-10
Assumed Mix of Building Types and Land Uses Impacted
Percent of Different Types of Building Development
Corresponding to Different Propagation Laws*
Land Use
High Density Urban
Low Density Urban
Suburban
Rural
*See Figures 5-16 through
High-Rise
100
50
0
0
5-18
Low-Rise
0
50
100
0
Open Space
0
0
0
100
5-42
-------
Table 5-11: Population Densities for Selected Areas of Motorcycle
Operation & Average Setback from Street
Urban
Land Use Area Low Density Suburban Rural
Average 8,473 2,286 20
Population
Per Square
Mile (Ref. 28)
Average 50 ft. 65 ft. 90 ft.
Setback
5-43
-------
Step 4 - The criteria for speech interference (percent sentence
intelligibility) by motorcycle acceleration noise is given in Figures
5-17 and 5-18 where the proportion of disturbance is plotted
as a function of the equivalent level (L ) of the intruding noise.
eq
Using the energy-averaged typical acceleration levels given in
Table 5-1 fry Lmax/ the L for the duration of a motorcycle acceleration
was calculi-.'• ; using the following equation (Ref. 17):
L = L - 10 log 2.3 (L - L )/10
eq max max b
where U,jax is the maximum level of a triangular time history and L^ is the
background level. Different outdoor ambient sound levels are assumed for
each land use area: 60 dB(A) for urban areas, 55 dB(A) for suburban areas,
and 45 dB(A) for rural areas (Ref. 12, 24). To determine the resulting
L level inside the home the following transmission losses were applied
to^the propagated noise levels/ depending on land use:
1. An attenuation of 20 dB was used for urban areas to represent
an average of the case in which (because of the type of building
construction) the windows of half of the homes are open and half
are closed (Ref. 29).
2. An attenuation of 15 dB is used for suburban and rural areas
to represent an average of the case in which the windows of all
homes are open.
Step 5 - The ENI for speech interference is obtained by multiplying
the number of people in each band for each land use by the fractional impact
criteria (percent speech intelligibility) given in Step 4.
Population distribution as a function of L , as calculated in
Step 3, is shown in Table 5-12 for each of the study regulatory levels.
The relative reduction in outdoor speech interference due to various
sound level limits occuring daily, outdoors and indoors, respectively, for
motorcycles appears in Figure 5-19. Tables 5-12, 5-13 and 5-14 show the
speech interference (ENI) as calculated in Step 5. The relative reduction
in indoor speech interferences is approximately the same as that shown in
Figure 5-19 for outdoor speech interference.
5-44
-------
Figure 5—17. Fractional Impact of Outdoor Speech Interference
too
o
c
01
Q.
|
<
O
til
o
z
Ul
GC
UJ
U.
CC
IU
X
U
IU
£
V)
LEVEL OF CONTINUOUS OUTDOOR NOISE CAUSING INTERFERENCE (Leq), dB(A)
NOTE: NORMAL VOICE AT 2 METERS WITH 60 dB(A) IN THE
ABSENCE OF INTERFERING NOISE
Source: Reference 12
5-45
-------
Figure 5—18. Fractional Impact of Indoor Speech Interference
IG'J
f-
2
IU
b
o
o
<
cc
u.
LU
o
z
IU
cc
IU
u.
QC
Ul
I
o
ai
ui
a.
V)
45
50
55
60
65
70
75
LEVEL OF COJSnriMUOUS NOISE CAUSING INTERFERENCE. dB(A)
5-46
-------
Figuio D-19. Rulntivo Reduction in Outdoor Speech Interferences due to
Motorcycle Noise
CURRENT IMPACT: 100%
NO IMPACT:
O
a.
2
z
ID
a:
cc
•3
o
.u..
O
DC
LL
83
80 78
MOTORCYCLE REGULATORY STUDY LEVEL dB(A)
•FRACTION OF MOTORCYCLES WITH MODiFIED EXHAUST SYSTEMS
5-47
-------
Tai 5-12. Inpact-Events* Distribution as a Function of L
eq
X
00
12% Modified
Regulatory
Level
Current
o c
85
f\ *\
83
ft /\
80
"t ft
78
M ••
75
3% Modified
Regulatory
Level
Current
85
83
80
78
75
85-80
1,083,000
n
n
n
n
n
271,000
it
n
n
n
n
80-^75
2,134,000
n
n
n
n
n
534,000
n
n
n
n
n
75-70
3,075,000
n
n
n
n
n
769,000
n
n
n
it
ii
70-65
16,200,000
14,570,000
13,030,000
10,570,000
9,950,000
8,890,000
13,950,000
12,160,000
10,460,000
7,740,000
7,060,000
5,900,000
65-60
31,890,000
30,430,000
29,030,000
25,950,000
24,320,000
19,790,000
24,360,000
22,750,000
21,200,000
17,810,000
16,020,000
12,570,000
60-55
50,690,000
49,030,000
47,590,000
44,360,000
42,810,000
40,410,000
35,320,000
33,500,000
31,820,000
28,350,000
26,640,000
23,990,000
-------
Table 5-13:
Outdoor Speech Interference (ENI) Occurring Daily Due to
Motorcycle Acceleration Noise (in Thousands)
Low Density
Urban
Suburban
Rural
Total
12% Modified
Regulatory
Level*
Current
85
83
80
78
75
7% Modified
Regulatory
Level
Current
85
83
80
78
75
3% Modified
Regulatory
Level
Current
85
83
80
78
75
0% Modified
1242
1059
963
834
807
732
474
459
408
394
381
350
Negligible
1716
1518
1317
1228
1188
1082
996
804
699
567
537
459
343
325
272
256
243
209
Negligible
1339
1129
971
823
780
668
798
597
492
351
321
240
236
218'
163
147
134
98
Negligible
n
n
n
n
1034
815
655
498
455
338
Regulatory
Level
Current
85
83
80
78
75
651
444
333
189
159
75
156
138
80
65
49
13
Negligible
n
n
n
n
n
807
582
413
254
208
88
* dB(A)^J331a
5-49
-------
Table 5-14: Indoor Speech Interference (ENI) Occurring Daily Due to
Motorcycle Acceleration Noise (in Thousands)
Low Density
Urban Suburban Total
12% Modified
Regulatory
Level
Current 201 254 455
85 183 229 412
83 168 214 382
80 147 192 339
78 138 189 327
75 126 174 300
7% Modified
Regulatory
Level
Current 156 189 345
85 138 165 303
83 120 147 267
80 99 129 228
78 90 120 210
75 78 105 183
3% Modified
Regulatory
Level
Current 120 138 258
85 102 111 213
83 84 94 178
80 63 76 139
78 51 67 118
75 39 49 88
0% Modified
Regulatory
Level
Current 93 98 191
85 75 71 146
83 57 51 108
80 33 33 66
78 24 25 49
75 12 7 19
5-50
-------
As discussed above, motorcycle impacts in low-density urban,
suburban and rural areas has been the focus of the speech interference
analysis. In most of these areas motorcycle accelerations stand out as
single events above a traffic stream. Excluding high-density urban areas,
where many instances of motorcycle noise standing out above traffic un-
doubtedly occur, was felt to be a reasonable balance for those low-density
urban, suburban and rural cases where motorcycle acceleration noise is
masked by traffic. However, potential impacts in high-density urban areas,
as a separate case, were also assessed. Assuming no traffic masking and
a representative background noise level, some 6.4 million potential impact-
events could be occuring daily in the U.S. in high-density urban areas due
to motorcycles alone. At the 75 dB(A) regulatory level these potential
impacts would fall to 4.4 million, a 29.6 percent decline. The relative
decline is considerably less than for low-density urban areas and about
the same as for the suburban case.
This speech interference analysis represents the change in impact
after the motorcycle population has been fully replaced at any given
regulatory level (i.e., all motorcycles in the population meet standards).
The fully implemented statistics are felt to be the most illustrative for
comparison of regulatory alternatives. The benefits, of course, would
occur gradually as older motorcycles are replaced by quieter models, with
approximately 90% of the ultimate benefits achieved four to five years
after the effective date of the final step standard.
These data are also based on the finding that, as a class average,
properly used and maintained motorcycles do not degrade significantly
over their expected life. Although certain models may degrade somewhat,
statistics indicate that other models actually become quieter with use
(see Chapter 6). This analysis also assumes that rapidly deteriorating
mufflers will be eliminated from the market (to the extent they are not
eliminated, they are included in the "percent modified" figures).
Figures 5-20 and 5-21 show the reduction in outdoor speech
interferences over time, projected for the years 1975 to 1990. Figure
5-20 illustrates the effect of reducing only the percentage of modified
motorcycles. It should be noted that if the percentage of modified motor-
cycles remains unchanged, outdoor speech interferences due to motorcycle
noise will increase over time, due to projected increases in the total
motorcycle population. Figure 5-21 details the reduction in such impacts
for various motorcycle regulatory levels. For illustrative purposes,
these figures assume that the number of modified motorcycles will be
reduced to 7 percent of the street motorcycle population. It should
also be noted that the relative benefits over time shown in Figures 20
and 21 for outdoor speech interference will be approximately the same for
other noise-induced activity interference effects, i.e., indoor speech
interference and sleep disruption.
5-51
-------
Figure 5-20.
Reduction in Street Motorcycle Impact (Outdoor Speech Interference)
Over Time — Effect of Reduced Modifications
200%
iu
tc.
cc
U
u. 100%
O
<
CC
0%
1975
12%* (CURRENT)
7%
3%
NO CHANGE IN NEW MOTOR-
CYCLE SOUND LEVELS -
EFFECT OF REDUCED
MODIFICATIONS ONLY.
1979 1980 1981
1984 1985
1990
•FRACTION OF MOTORCYCLES WITH MODIFIED EXHAUST SYSTEMS.
5-52
-------
Figure 5-21. Reduction in Street Motorcycle Impact (Outdoor Speech Interference;)
Over Time — Three Reguliitory Options
200%
100%
7% LEVEL OF
EXHAUST MOD!
FICATIONS
83/00
83/SO/78
1975
1979 19SO 1S81
1984 1985
1990
5-53
-------
5.5.2 Sleep Disturbance
Sleep periods of humans are typically classified into five stages,
In stages I and II sleep is light and the sleeper can be easily awakened.
Stages III and IV are states of deep sleep in which a person is not as
easily awakened by a given noise, but such a stimulus may cause a shift
to a lighter stage of sleep. An additional stage of sleep is the rapid
eye movement stage (REM), which corresponds to the dream state. When
exposed to an intrusive noise, a sleeper may (1) show response by a brief
change in brainwave pattern, without shifting sleep stages; (2) shift to
a lighter sleep stage; or (3) awaken. The greatest known impact occurs
due to awakening, but there are also indications that disruption of the
sleep cycle may cause other behavioral changes (irritability, etc.) even
though the sleeper may not awaken (Ref. 13) .
Recent studies (Ref. 19, 38) have summarized and analyzed sleep
disturbance data. These studies show a relationship between frequency
of response (awakening or disturbance) and the sound level of a noise
stimulus, and determined as well that the duration of the noise stimulus
was a critical parameter in predicting response. The studies also showed
that the frequency of sleep disruption is predicted by noise exposure
better than is arousal or behavioral awakening. Sleep disturbance is
defined as any physiological change which occurs as a result of a stimu-
lus. The person undergoing such disturbance may be completely unaware
of being affected; however, such disturbance may disrupt the total sleep
quality and thus lead to, in certain situations, behavioral or physio-
logical consequences (Ref. 13).
The fractional impact of the disruption of sleep is given in
Figure 5-22 where the frequency of no sleep disturbance (as measured by
changes in sleep state, including behavioral awakening) is plotted as
a function of 'the Sound Exposure Level (SEL) of the intruding noise.
Similarly, the frequency of behavioral awakening as a function of SEL
is shown in Figure 5-23. These relationships, adapted from Figures 5-1
and 5-2 of Reference 19, consist of data derived from a review of the
recent experimental sleep and noise exposure relationship data.
Figures 5-22 and 5-23 indicate the approximate degree of impact
(percent disruption or awakening) as a function of sound exposure level.
The noise data contained within these references were measured in terms
of "effective perceived noise level" with a reference duration of 0.5
second (EPNLn ,- ). EPNL-, ,- is converted to Sound Exposure
_ - - __. _ _ U • J 5Qw« _ U • D . S6O* . _ . _ ,
_ - - __. _ _ • J w« _ • . * . _ . _ ,
Level (SEL) by using the following approximate relationships:
5-54
-------
Figure 5-22.
Fractional Impact of Sleep Disruption as a Function of Sound Exposure
Level 19 (Regression of Sleep Disruption on SEL)
100-
90-
~ 80H
o
I
oc
CO
5
Q.
ui
<";
gg
70-
60-
g& 50-
ui
40-
30-
20-
10-
SLEEP DISRUPTION
Fl = .0135 {SEL-37)
30
40
I
50
60
70
80
90
100
110 120
SOUND EXPOSURE LEVEL (SEL). dB(A)
Source: Reference 19
(Regressions of Sleep Disruption on SEL Revised)
5-55
-------
5—23. Frequency of Arousal or Awakening from Sleep in Collogn or Middle-Aged
Men and Women as a Function of Sound Exposuic Level (Regressions of Percent
Awakened on SEL. Revised)
100
SLEEP AWAKENING
Fl= 0.0119 (SEL-50)
110
SOUND EXPOSURE LEVEL (SEL).dB(A)
130
Source: Reference 19
(Regressions of Percent Awakened on SEL, revised)
5-56
-------
SEL = EPNL - 16 dB
0.5 sec
The SEL is defined as:
,t 2
SEL = log f P(t) dt
10 J ~~2~
' P
0 o
where:
t is the duration of the noise
P(t) is the A-weighted sound pressure as a function of time
and,
P is the reference pressure
o
For triangular time histories such as vehicular accelerations,
an approximation is
SEL = L + 10 log t/2
max 10
where
L is the maximum A-weighted sound level
max
and
t is the duration in seconds measured between the "10 dB(A)
down" points where the sound level is equal to L - 10.
max
For the purpose of this analysis, t is equal to the duration of a
representative motorcycle acceleration, assumed to be 8 seconds.
Using the representative energy-averaged acceleration levels
given in Table 5-1 for I^x/ the SEL's were found for each motor cycle
type. Before the fractional .^pact was computed, the same reductions in
sound levels due to transmission through walls which were used in Section
5.5.1 were taken into account.
5-57
-------
As discussed on page 5-36, this analysis uses 5% as the fraction
of street motorcycle mileage which occurs during nighttime hours. As
discussed above, this may over- or underestimate the actual impact on
sleep, but the relative impacts and reductions are unaffected by this
assumption. Although some fraction of the population sleeps during the
daytime, it is also assumed for purposes of this analysis that sleep only
occurs during the nighttime hours.
Propagation loss is computed for each land use category in the
same manner as discussed in Section 5.5.1. Again, the distances from the
roadway at which the acceleration sound levels fall off in 5 dB(A) steps are
computed, and the equivalent number of "impacted people" per mile living
within each band is derived using the fractional impact relationship shown
in Figures 5-22 and 5-23. These numbers are multiplied by the number of
nighttime motorcycle acceleration miles to give the total potential sleep
disruption and sleep awakening (ENI) due to motorcycle acceleration noise.
Population distribution according to SEL is shown in Table 5-15.
The sleep disruption ENI is given in Table 5-16 for the various study
levels, and translated into percent reduction from the current baseline
in Figure 5-23. The sleep awakening ENI is indicated in Table 5-17.
The associated percent reduction in sleep awakening is approximately the
same as that for sleep disturbance, indicated in Figure 5-24.
5.5.3 Other Factors in Reduction of Single-Event Noise Impact
Most commonly used social indicators of the effects of noise and
subsequent human response assess the impact of noise primarily in terms of
simple A-weighted sound levels or exposure (Refs. 12, 13). The above
analysis has used this measure exclusively. The presence of identifiable
pure tones, however, and other properties of the sound signal independent
of amplitude or frequency distribution are also known to annoy or otherwise
impact humans in a manner not adequately predicted by a time-integrated
A-weighted measure. For example, pure tone components in aircraft noise
are known to be more annoying than broadband noise at the same sound level.
There exist several characteristics of motorcycle noise signals
which may result in greater subjective annoyance than would be predicted
by simple sound level measures. The irregular impulsiveness of two-stroke
engines, for example, and the high frequency tones associated with engine-
related mechanical sounds are two characteristics of motorcycle noise that
are not properly reflected in currently used sound descriptors. Except
for'Italian noise standards (see Section 3), EPA knows of no accepted
motorcycle noise rating that accounts for these specific temporal and
spectral properties of motorcycle noise. The time-integrated A-weighted
sound level still remains as the best descriptor currently available for
characterizing motorcycle noise.
5-58
-------
It should be noted that there is an additional, fundamental problem
associated with assessing the objectionable qualities of motorcycle noise.
Specifically, some segments of the population are undoubtedly annoyed by
motorcycle noise for reasons that have little to do with the sound emitting
characteristics of the vehicle. Negative reactions to apparent land de-
struction, dangerous driving habits and other factors emotionally associated
with the motorcycle may be triggered by the mere audible detection of a
motorcycle. This does not, of course, negate the fact that people are still
annoyed by motorcycle noise even though that response is in some cases an
outlet of other, more general reactions to the motorcycle or its operator.
Such emotionally associative responses to noise are commonly experienced
with other sources of noise as, for example, annoyance with airo noise
mediated by a fear of aircraft crashes (Ref. 40).
As motorcycle noise emissions are lessened, the number o-' oople
who can audibly detect the presence of the motorcycle will be rec .:ed
and, accordingly, the general negative reactions discussed above .should
not occur as often. However, for those individuals within the popula-
tion segment still exposed to motorcycle noise (even at a reduced level),
this "mediated" annoyance may not be significantly reduced. Due to this
associative effect a full reduction in motorcycle noise impact may not
be fully realized.
5.5.4 Summary
It is to be noted that the preceding analysis of street motorcycle
noise impact is meant to be a conservative estimate of the dimensions of
this problem. The various assumptions which must necessarily be made in an
analysis of this nature have been consistently made with the intent that
any error would tend to underestimate, rather than overestimate the amount
of impact. It is quite possible that the impact figures which are derived
"in the analysis do substantially underestimate the actual impact of motor-
cycle noise on the public health and welfare.
The following are some of the assumptions made in the analysis
which could have the effect of understating the magnitude of total impact
from street motorcycles:
(a) Percentage of exhaust system modifications. Rather than the
12% figure used some authorities estimate much higher number of modifica-
tions. Spot checks in several locales (mostly in Southern California)
have seen up to 40% of the motorcycles observed having replacement exhaust
systems.
(b) The analysis measures impact occuring only from motorcycle
accelerations. Some amount of impact almost certainly occurs during
deceleration and cruise conditions.
(c) The proportion of mileage accumlated during the night is
assumed to be 5%. This could be significantly understated, in which case
the numbers of sleep disturbances would also be understated.
5-59
-------
Figure 5—24. Relative Reduction in Slcrp Disruption Due to Motorcycle Noise
;UR RENT IMP ACT: 100%
o
c_
S
2
u
o:
cc
O
2
O
O
<
cc
NO IMPACT:
80% -^^^^^^r
60%
40%
20%
0%
12%*
CURRENT
0%
83 80 78 75
MOTORCYCLE REGULATORY STUDY LEVEL tlB(A)
•FRACTION OF MOTORCYCLES WITH MODIFIED EXHAUST SYSTEMS
5-60
-------
Table 5-15: Population Distribution as a Function of SEL
85-80 • 80-75 75-70 70-65 65-60 60-55 55-50 50-45 45-40 40-35
12% Modifications
Regulatory Level
Current
85
83
80
78
75
3% Modifications
Regulatory Level
Current
85
83
80
78
75
4680 36,000 47,000 74,000 178,000
60,000 150,000
" " " " 125,000
" " " " 96,000
» " » 88,000
n n n n n
1170 9100 11,700 32,000 121,000
15,000 90,000
" " " 63,000
n n n n 31,000
" » » » 22,000
n n n n n
343,000
311,000
283,000
234,000
210,000
171,000
235,000
200,000
169,000
115,000
89,000
46,000
423,000
408,000
390,000
373,000
343,000
264,000
255,000
239,000
219,000
201,000
167,000
80,000
539,000
501,000
483,000
443,000
433,000
412,000
309,000
268,000
247,000
204,000
193,000
170,000
601,000
519,000
484,000
469,000
457,000
439,000
330,000
239,000
201,000
185,000
171,000
152,000
346,000
369,000
351,000
346,000
312,000
307,000
142,000
167,000
148,000
142,000
104,000
98,000
-------
Table 5-16: Sleep Disruption (ENI) Due to Motorcycle Acceleration Noise
(in Thousands)
Low Density
Urban Suburban Rural Total
12% Modified
Regulatory
Level*
.Current 1050 788 Negligible 1838
85 957 711 " 1668
83 888 657 " 1545
80 789 561 " 1350
78 744 510 " 1254
75 636 443 " 1079
7% Modified
Regulatory
Level
Current 840 682 Negligible 586
85 744 599 " 1343
83 669 541 " 1210
80 567 441 " 1008
78 519 388 " 907
75 402 316 " 718
3% Modified
Regulatory
Level
Current 672 595 Negligible 1267
85 573 510 " 1083
83 495 450 " 945
80 387 345 " 732
78 336 290 " 626
75 216 214 " 430
0% Modified
Regualtory
Level
Current 549 530 Negligible 1079
85 444 443 " 887
83 366 381 " 747
80 255 274 " 529
78 201 216 " 417
75 78 138 " 216
*dB(A)-J331a
5-62
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Table 5-17: Sleep Awakening (ENI) Due to Motorcycle Acceleration Noise
(in Thousands)
Low Density
Urban Suburban Total
12% Modified
Regulatory
Level
Current297 272 569
85 261 238 499
83 243 221 464
80 222 189 411
78 198 169 367
75 177 149 326
7% Modified
Regulatory
Level
Current 240 229 469
85 201 194 395
83 183 176 359
80 159 143 302
78 145 120 265
75 114 98 212
3% Modified
Regulatory
Level
Current 192 196 388
85 153 158 311
83 135 140 275
80 111 107 218
78 84 82 166
75 63 60 123
0% Modified
Regulatory
Level
Currentr 159 172 321
85 117 134 251
83 99 114 213
80 72 78 150
78 48 53 101
75 24 31 55
5-63
-------
(d) Distribution of mileage accumulated in the different popula-
tion density areas is an estimate and could result in understating impact
if more usage occurs in suburban areas than is assumed.
(d) The sound propogation patterns used in assessing impact are
conservatively biased. For the sake of simplicity persons within a 70
dB noise band are assumed to experience only 70 dB, even though the actual
exposure could be 71, 72, 73 or 74 dB.
It is clear from the analysis of street motorcycles that both
modified and unmodified motorcycles cause significant noise impact on the
population. Although exhaust system modifications do account for a large
portion of motorcycle noise impact, unmodified motorcycles are also
substantial contributors to the problem. It is apparent that the most
effective means of reducing the noise impact of street motorcycles is to
control the numbers of exhaust system modifications while at the same
time lowering the sound levels of unmodified vehicles.
5.6 Analysis of Noise Impact of Motorcycles Used Off-Road
This -analysis addresses the in; -.-:t of regulations to limit the
noise from motorcycles used off-road. oise from off-road use of motor-
cycles is considered to be a problem c< significant proportions. In a
survey of 250 senior Federal and state managers of public lands, forests,
lakes, parks and wilderness areas of the United States regarding the
adverse effects of off-r.oad recreational vehicles (which included other
factors besides noise), trail mo tor cycles-were rated as the "most urgent
problem for them to solve" (Ref. 3). Minibikes (considered as motorcycles
in this analysis) and snowmobiles (when in season), were listed as second
and third priorities, with about one-half the frequency of response.
In a survey which addressed public attitudes toward different
noise sources, the largest number of respondents said they were "very
much" annoyed by noise from trail motorcycles, even though motorboats,
automobiles, and children were heard more "often" by respondents. A
total of nearly 30 of the 113 people hearing trail motorcycles said they
were "very much" annoyed, and approximately 10 of the remaining persons
said they were annoyed "quite a lot" (Ref. 4).
In a U.S. Forest Service study, seven experienced recreation
guards at the Oregon Dunes National Recreation Area rated the noisiness
of dune buggies as to acceptance by the public (Ref. 21). While moving
at 10 mph up a grade, the dune buggies were accelerated full-throttle
for a distance of 50 feet. The listeners were placed 50 feet from the
midpoint of the acceleration, perpendicular to the dune buggy path. The
results of this experiment are shown in Figure 5-25.
It is estimated that approximately one half of all recreational
off-road vehicle use in the United States takes place on lands administered
by the Bureau of Land Management (BLM). BLM lands comprise some 20% of
total U.S. land area, accounting for about 60% of all lands owned by the
5-64
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Federal government. Over half of ORV use takes place in the following
areas: Alaska; western Arizona; southern California; southern Nevada
and central Utah.
-BLM has the authority to close certain areas to off-road vehicle
use, if such use endangers soils, vegetation, archeological sites or other
valuable resources. Designation of lands as closed to ORV use involves
a public notification and participation process which can take a number of
months to complete. The Bureau is currently in the process of evaluating
all lands under its control to determine their designation either as closed
or open to ORV use.
5.6.1 Distribution of Off-Road Motorcycle Sound Levels
Sound levels of current non-competition off-road motorcycles
are to a large extent dependent upon the size of the vehicle. The data
in Appendix C and data submitted by manufacturers indicate that small
off-road machines of 170 c.c. or less have a median acceleration sound
level (J-331a) of about 80 dB(A), while the sound levels of off-road
motorcycles over 170 c.c. displacement range from 86 to 95 dB(A). Of
the total current population of off-road motorcycles, 73% fall into
the smaller displacement category; 27% into the larger. The following
average sound levels are assumed for the purposes of this analysis
(Sec. 3):
< 170 c.c. 80 dB(A)
> 170 c.c. 89 dB(A)
Representative acceleration sound levels are assumed to be 3
dB(A) lower than these levels,the same assumption as made for street
motorcycles (Appendix G). The standard deviation for each group is
assumed to be the same as that for street motorcycles.
Exhaust-modified off-road motorcycles are assumed to have the
same J-331a sound level distribution as exhaust-modified street motor-
cycles (shown in Figure 5-2), and representative acceleration levels
3 dB less than the J-331a level. The various regulatory options consi-
dered for off-road motorcycles are indicated in Table 5-18.
Off-road mileage by motorcycles is approximately 10 million miles
daily (Ref. 8). Table 5-19 shows the off-road motorcycle mileage mix
estimated by the Motorcycle Industry Council (MIC). According to MIC, 57
percent of all off-road mileage is accumulated by street and dual purpose
motorcycles. It can be seen that regulation of motorcycles designed for
use on streets will have a significant effect on reducing the impact from
off-road motorcycle usage.
The use of motorcycles which are designed for competition use in
off-road areas also contributes to noise impace in such areas. Sound
levels of competition-type motorcycles generally exceed 90 dB(A), with
5-65
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Figure 5-25. Subjective Noise Rating of Dune Buggy Noise Levels
105
110
dBA, SOUND LEVEL METER, FAST RESPONSE
1) Very poor; noise completely unacceptable to almost all users.
2) Poor; noise unacceptable to most users.
3) Acceptable to most users, marginal.
4) Good; noise mildly offensive to some users.
5) Excellent; noise not offensive to most dune users.
(Soutcc: Reference 2l)
-------
Table 5-18: Regulatory Options Considered for Off-Road Motorcycles
Single Class Regulatory Options (dB(A))*
Option
1
2
3
4
1979
86
86
86
86
1981
-
83
83
83
1984
-
-
80
80
1988
-
-
-
78
Two Class Regulatory Options (dB(A))
Option 1979 1981 1984
la 86/83* 86/80 86/78
2a 86/83 83/80 83/78
3a 86/83 83/80 80/78
*Motorcycles over 170 c.c.: 86 dB(A;
Motorcycles under 170 c.c.: 83 dB(A)
Not-to-exceed Sound Levels as measured by F-76a procedure
Production levels are assumed to be 2 dB lower than these
regulatory levels, as discussed in the text.
*Accelerated lead times, with effective dates of 1979, 1980, 1982 and
1985, and more extended lead times, with effective dates of 1979, 1982,
1986 and 1991 have also been analyzed for the regulatory options listed
above.
5-67
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Table 5-19: Off-Road Motorcycle Mileage Mix (Ref. 8)
Annual Mileage
(Billions) % of Total
Street-Use Motorcycles
Unmodified 1.85 50
Modified .26 J_
Total 2.1 57
Off-Road Motorcycles
Unmodified 1.2 32
Modified .4. 11
Total 1.6 43
Total Off-Road Mileage
From All Motorcycles 3.7 100%
5-68
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many exceeding 100 dB(A). Such levels dramatically increase the de-
tectability distances of these vehicles (discussed below), resulting in
relatively large land areas being impacted. Although the numbers of
competition motorcycles which are used off-road are not known, most land
management officials contacted by EPA reported that such vehicles consti-
tute a very significant part of the off-road vehicle noise problem. Labels
and other means of distinguishing competition motorcycles from off-road
motorcycles, combined with well planned and enforced land use restrictions
are considered to be the most effective means of dealing with the problem
of competition motorcycles used in off-road areas.
5.6.2 Detectability Criterion
Off-road motorcycle operations often occur in areas with otherwise
low ambient levels, near quiet suburban areas or more remote areas where
people are hiking, camping and pursing other activities where man-made
sounds are usually undesirable. In such situations, motorcycle noise is
preceived by the listener as being alien to the environment and therefore
an objectionable intrusion. For these reasons "detectability" is considered
to be the best criterion for the impact of off-road motorcycle operations.
In Reference 22, "detectability distances" are calculated by
a method described in Reference 23 for various types of vehicles under
"typical" forest conditions where the background sound level is assumed
to be 40 dB(A). The detectability distances are 1400, 2600 and 3900 feet
for motorcycles with reference sound levels at 50 feet of 74, 83 and 93
dB(A), respectively. Detectability distance is defined as the distance
at which 50 percent of the listeners with a "40 percent hearing efficiency"
would detect a given sound level with a one percent false alarm rate. A
40 percent hearing efficiency means a person not only has good hearing
but is a "good listener".
A more typical value of hearing efficiency for persons in remote
or rural areas would be 20 percent, which would reduce the above described
detectability distances by a factor of about 2 (Ref. 36). Therefore,
detectability distances of 700, 1300 and 1950 feet from motorcycles with
reference sound levels of 74, 83, and 93 dB(A) at 50 feet, respectively,
are assumed to apply in quiet remote areas, with typical forest background
levels of 40 dB(A).
In Reference 24 a single test is described where, at a distance
of 1000 feet, only a few listeners from a group of seven could hear the
maximum acceleration noises from three dual—-.•-roose motorcycles being
operated simultaneously (the sound level at feet should have been
approximately 85 dB(A)). In the same study, -cectability is presented
as a function of distance for typical and qir :c forest conditions and for
typical trail motorcycle operations. Typically, less than 20 percent of
motorcycles used off-road are heard beyond a distance of 1000 feet with
usual forest background sound levels. For quiet forest conditions, the
detectability distance for a given detection percentage is approximately
doubled.
5-69
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Figure 5-26 illustrates this relationship between detectability
distances and 50-foot acceleration sound levels. For simplicity of
analysis, it is assumed that all persons within the detectability
distances will perceive the motorcycle noise and that none beyond the
detectability distance will perceive the motorcycle.
5.6.3 Off-Road Motorcycle Operations
Off-road motorcycle riding typically consists of numerous low-
speed, near full-throttle accelerations interspersed with quieter cruise
and deceleration operations. Figure 5-27 illustrates two cases of in-
terest: the case of a motorcycle being used on a trail or cross-country,
and the case of a motorcycle operating within an ORV (off-road vehicle)
area where other ORVs are also likely to be operating at the same time.
The circles indicate the distance from each acceleration at which noise
exceeds a given criterion level, i.e., the criterion distance.
In the case of a motorcycle being operated on a trail it can be
seen that if the criterion distance is large enough so that it is a sig-
nificant fraction of the straight-line distance between accelerations,
the impacted area is approximately the sum of the straight-line distances
between accelerations multiplied by double the criterion distance for the
low-speed, high acceleration case. Since detectability distances for off-
road motorcycle noise are on the order of one-half mile, the criterion
distance is typically a significant fraction of the straight-line travel
distance. This model of a typical impacted area is assumed to apply for
trail and cross-country riding. All persons within the impacted area
are impacted at least once with noise above the criterion level.
For the case of motorcycles being operated in an off-road vehicle
area, it is assumed that all persons within the boundaries of the area
are ORV operators who are not greatly annoyed or otherwise impacted by
ORV noise. Therefore, the impacted area would be the area bordering the
ORV boundary which is within the criterion distance of the boundary,
i.e., its size is the criterion distance multiplied by the approximate
perimeter of the ORV area. It can be seen that the relative reduction
in area impacted above a criterion level when a motorcycle is quieted a
given amount is the same for operations on the trail or relatively large
ORV areas.
5.6.4 Estimate of Current Noise impact
The impact of noise from off-road motorcycle operations is more
difficult to quantify in terms of the "people impact" criteria used in
the street motorcycle analysis. Based on the information available
an impact estimate was developed as described below.
5-70
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Figure 5-26. Assumed Dotectnbility Distance of Motorcycle Sound Under Typical
Forest Conditions
105
CQ
LU
IU
Lk
o
in
u.
O
U.I
u
•a
Q
LU
O
2
in
cc
LJ
LL
UJ
OL
IU
>
LU
_l
O
2
O
to
LU
_l
O
o
cc
o
o
100
95
90
85
80
75
70
7
V
500 700 1000 1GOO 2000
DETECTABILITY DISTANCE (FEET)
3000
5-71
-------
Figure 5-27. Illustration of Off-Road Operations
POI NT OF ACCELERATION
CRITERION
DISTANCE
BOUNDARY OF
ORV AREA
ORVAREA
OPERATIONS
TRAIL/CROSS-COUNTRY
OPERATIONS
-------
Off-road mileage by motorcycles is estimated to be 10 million
miles daily (Ref. 8). For illustrative purposes it could assumed that,
on the average, there are three motorcyclists riding off-road together.
Increasing the number of motorcycles operating together does not sig-
nificantly increase the detectability range (Ref. 16), so the effect
is that of reducing the total effective mileage by a factor of 3, to
approximately 3.3 million miles daily. Based on the average detecta-
bility range of one-quarter mile, the average motorcycle is heard within
a path one-half mile wide, so the 3.3 million effective miles form an
area of 1.65 million square miles which is exposed daily to noise above
detectability levels.
Some of the miles will overlap; i.e., the same or other motor-
cycles will impact the same area more than once. If we assume again,
for illustrative purposes, that this overlap reduces the area by a factor
as great as 50, the people within 33,000 square miles of area will hear
motorcycles used off-road at least once a day. Operations of off-road
motorcycles account for almost 35% of this impacted area, while dual-
purpose motorcycles account for approximately 25%. Modified motorcycles
account for over 40% of the impacted area.
Assuming a population density of 20 persons per square mile
(equivalent to a rural population density) approximately 660,000 persons
would be exposed at least once daily to noise from motorcycle operations
off-road. If only 5 percent of these total miles are in the vicinity
of campgrounds, small towns, and quiet suburban areas where background
sound levels are low and the outdoor population density may be on the
order of 1,000 people per square mile,-nearly 1.7 million additional
people could be impacted above the detectability criterion.
In the case of such populated areas which are exposed to off-
road motorcycle noise an analysis similar to that used to assess street
motorcycle noise impact can be performed. Using the 5% figure for off-
road motorcycle mileage occurring in these areas it can be calculated
that approximately 2.1 million speech interferences could occur daily
from this type of off-road motorcycle usage. Impact reductions which
may result from Federal noise regulation and in-use enforcement can be
similarly calculated. Without regulations for off-road motorcycles,
a street motorcycle standard of 78 dB(A) (which includes dual purpose
motorcycles), and a reduction in exhaust system modifications to 3% of
the street motorcycle population accomplishes a 15% reduction in this
speech interference impact. With noise emission standards of 83 dB(A)
and 78 dB(A) for large and small off-road motorcycles respectively,
off-road and exhaust modifications limited to 8% speech interference
impact will be reduced by approximately 80%.
5-73
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5.6.5 Relative Reduction in Noise Impact
The above numbers on the current impact of off-road motorcycles
are illustrative only since statistics on areas of operation and popula-
tion impact are unavailable. More reliable statistics can be developed
on the relative reduction of the current impact to be expected from
various regulatory alternatives.
Using detectability distance as the noise impact criteria, the
relative reduction in land area impacted by off-road motorcycle noise
above the criterion level can be calculated in the same manner as was
done for the street motorcycle analysis.
Detectability distance as a function of motorcycle reference (50
feet) sound level is plotted in Figure 5-26. The average detectability
distance can be calculated by selecting the detectability distance from
Figure 5-26 for each possible motorcycle reference sound level; multi-
plying each detectability distance by the fraction of motorcycles with that
reference sound level; and summing the results for unmodified street-use
motorcycles, unmodified off-road motorcycles, and modified motorcycles.
The resulting summations can be weighted by the fractions of motorcycles
of each type, and the results summed to obtain the overall average detecta-
bility distance. This can be repeated for various study levels and assumed
percentages of exhaust-modified motorcycles to obtain different equivalent
detectability distances. The relative decrease in equivalent detectability
distance represents tho relative decrease in impact.
Figure 5-28 is based on the estimated mileage mix shown in Table
5-19. This figure assumes that all street and dual-purpose motorcycles
are limited to a regulatory study level of 80 dB(A), reducing the average
detectability distance to 83% of its current value. Also illustrated
are the additional relative reductions in detectability distance due to
quieting off-road unmodified motorcycles and limiting off-road modified
motorcycles. As shown, an 80 dB(A) regulatory level for off-road motor-
cycles (exhaust modifications reduced to 16%) would accomplish a 28%
reduction in the amount of land area impacted by off-road motorcycle
noise when combined with the 80 dB(A) standard for street and dual pur-
pose motorcycles. Similarly, a 78 dB(A) regulatory level for off-road
motorcycles, with 8% modifications, would yield.a 36% reduction in noise
impacted land area.
Based on the estimate of over 2 million people currently impacted
one or more times daily by noise from off-road use of motorcycles,
limiting street and dual-purpose motorcycles to 80 ciB(A) would eliminate
the impact on approximately 345,000 people. Quieting unmodified off-road
motorcycles would eliminate the impact on an additional 70,000 to 300,000
people for study level limits of from 85 to 78 dB(A). If the number of
modified off-road motorcycles is reduced to 8%, impact would be eliminated
for an additional 185,000 people.
5-74
-------
Figure 5-20. Relative Reduction in Arcii Impact of Off-Ro;id Motorcycles (Assuminn
Street and Diiitl-Purpose Motorcycles are Regulatocl to 80 dU(A) with 3% Modifications)
CURKENT IMPACT 100%
MO IMPACT
H
8
H
EH
I
80%
GO0/
40%
20%
0%
26%*CURRENT
16%
S%
0%
86 83 80 78
MOTORCYCLE REGULATORY STUDY LEVEL dB(A)
•FRACTION OF EXHAUST-MODIFIED OFF-ROAD MOTORCYCLES
5-75
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Figure 5-29 shows the relative reduction in impact from quieting
off-road motorcycles alone, without considering dual-purpose motorcycles
which will be subject to standards for street motorcycles.
Additional reductions in detectability distances would be
achieved with a two-class regulation, assuming a 78 dBA regulatory level
for small off-road motorcycles (less than 170c.c.). Figure 5-30 illu-
strates the effect of establishing separate sound level standards for
small and large off-road motorcycles.
5.7 Operator and Passenger Noise Impact
The information in Appendix E indicates that sound levels at the
motorcycle operator's and passenger's ear during rapid acceleration are
approximately 100 dB(A), discounting wind and helmet effects. Although
this data was collected for only three large displacement motorcycles
and does not represent a valid statistical sample, it is not expected
that operator ear levels would differ dramatically among motorcycles
having similar wayside acceleration sound levels (81-84 dB(A) at 50
ft.). (Recently-gathered inforr-.ition is included in Appendix H).
The impact of motorcycL operator noise exposure is calculated
below in two ways. First, the rly equivalent exposure (Leq (24))
is assessed for three types of .- >rcycles: Playbike—smaller motorcycle
used for pure recreation; Comrr!ii motorcycle—medium sized motorcycle
used for urban and suburban tra: . .station; Touring motorcycle—large
motorcycle used for long distant- touring. In each case assumptions
are made about the numbers of hours of operation representative of heavy
but not intensive use and the fraction of time spent in the acceleration
node. Cruise operational levels are sufficiently below acceleration
•levels to be considered negligible for Leq calculations. In each of
the three situations, the yearly Leq for motorcycle (alone) exposure
is within 5 or 6 dB of the L (24) 70 dB no-effect level listed in the
Levels Document (Ref. 12) as requisite* to protect the public health and
welfare with an adequate margin of safety.
These calculations were repeated for off-road motorcycles.
Off-road non-competition motorcycles exhibit J-331a levels of up to 90
dB(A) and above. It is assumed for analysis purposes that 105 dB(A)
during rapid acceleration is representative of off-road motorcycles in the
86-88 dB(A) (J331a) range. Two off-road use situations were analyzed:
moderately heavy use (2000 miles annually) and heavy use (4000 miles
annually). The yearly L for these cases exceed 70 dB by 10 and 13 dB
respectively. ^
5-76
-------
Figure 5-20. CiolatJvi! Reduction in Area Impact of Off-Ho;itl Mctorcyclus Only
CURRENT IMPACT 100%
NO IMPACT
EH
"Z,
U
2
O
H
E-i
H
80%
60%
40%
20%
OP/
/O
86 85 83 80
MOTORCYCLE REGULATORY STUDY LEVEL clB(A)
26%*
CUP-RENT
16%
8%
0%
78
•FRACTION OF EXHAUST MODIFltD OFF-ROAD MOTORCYCLES
5-77
-------
Figure 5-30. Relative Reduction in Area Impact of Off-Roml Motorcycles Only,
Assuming 8% Exhr.nst Modified
CURRENT IMPACT 100%
D
U
§
H
E-i
U
NO IMPACT
80%
60%
40%
20%
SINGLE CLASS REGULATORY OPTION
TWO CLASS REGULATORY OPTION*
86 83 80 78
MOTORCYCLE REGULATORY STUDY LEVEL dD(A)
•MOTORCYCLES LESS THAT 170cc: 78 dB(A) REGULATORY LEVEL.
5-78
-------
Operator sound level reductions are expected as motorcycles are
redesigned to meet wayside standards. A biproduct of reducing street
motorcycles 5 or 6 dB would undoubtedly be a reduction in operator expo-
sure from street motorcycles to very near the protective L (24) 70 dB
criterion. Reducing off-road sound levels under rapid acceleration to
100 dB(A) would reduce the off-road exposure considerably although not
as low as the 70 dB(A) level.
These calculations are for motorcycle (only) contributions.
Wind-induced turbulence can add to operator exposure. Use of helmets,
however, can abate exposure in some instances although in certain fre-
quencies and at certain head attitudes the sound level can be enhanced.
Helmet-induced turbulence may also be significant.
Motorcycle noise exposure may not be the only source of high
intensity noise experienced during a motorcyclist's day. A motorcyclist
may have a high-noise working environment, may use noisy forms of trans-
portation and may experience other noise exposure. Motorcycle noise
would be an addition to this exposure, which in conjunction, may pose a
hearing hazard. The second method of analyzing operator impact, there-
fore, is to compute the combined Leq for motorcycle and non-motorcycle
exposure for different yearly durations of motorcycle use as shown in
Table 5-20.
The benefit derived from noise reductions at the operator's
position was quantified usirig a method which calculated an Equivalent
Noise Impact on Hearing (ENIH) for hearing damage risk (Ref. 4). This
concept is based on a nonlinear relationship between hearing loss and
daily (24 hour) exposure to equivalent sound levels above 70 dB. The
exposure is for a period of 40 years. This method provides a quantitative
approach to assess severe health damage and hearing loss for exposure
above L (24) = 70 dB. The procedure used in this analysis estimates
the benefit in terms of reduction of Noise-Induced Permanent Threshold
Shift (NIPTS) due to noise reductions from motorcycles. In this analysis
NIPTS is defined as the anticipated change in threshold for the average
of the frequencies 500, 1000, 2000 and 4000 Hz beyond that change which
will occur due to the normal aging process. The average NIPTS for people
exposed to noise daily over 40 years is estimated and defined by a frac-
tional index for hearing as:
2
FIH - 0.025 (L (24) - 70)
'eq
5-79
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Table 5-20
EQUIVALENT SOUND LEVELS FOR OPERATOR EXPOSURE*
Street Motorcycle
Off-Road Motorcycle
Recreation Commuter Touring
Fifty-foot 80 82 82
Acceleration Level
(dB(A)-J-331a)
Sound Level at 98 100 100
Operator Ear Position
(full-throttle
acceleration — dB(A) )
Sound Level at Operator 95 97 97
Ear Position (rapid
acceleration — dB(A) )
Percent of Operation 50/50 20/80 10/90
Time Spent in Acceleration
and Cruise Modes
(Acceleration/Cruise)
Equvilent Sound Level 92 90 87
for an Operating Cycle
(dB(A))
Annual Distance 1000 4000 10000
Travelled (miles)
Average Speed 15 25 40
(miles/hour)
Annual Time of 65 160 250
Operation (hours)
Yearly Leq (24)— (dB(A)) 71 73 72
Moderate Use Heavy Use
86 86
105 105
102 102
50/50 50/50
99 99
2000 4000
15 15
125 250
81 84
^Motorcycle alone contribution—wind turbulence and helmet effects not included.
5-80
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The fractional index is representative of the average number of
decibels of hearing an individual might be expected to permanently lose
(averaged over the four reference frequencies) over 40 years of exposure
to a given 24-hour LSQ.. As an example, a person exposed to L (24) =75
dB(A) over 40 years would be expected to lose a little less than 1 dB in
hearing; L = 80 dB(A) would translate into 2.5 dB loss. The fractional
indices of NIPTS contained in Table 5-21, then, can be used to calculate
the relative reduction in expected hearing loss at any level of operator
exposure reduction. The Table indicates a 5 dB reduction in off-road
duty-cycle operator exposure from 100 to 95 dB(A) would reduce the motor-
cycle-induced portion of NIPTS over 40 years by 50 to nearly 100% for all
cases except very heavy use (400 hours annually).
5-81
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Table 5-21
COMBINED EFFECT OF MOTORCYCLE AND NON-MOTORCYCLE EXPOSURE
Combined L (24) for Motorcycle and Non-Motorcycle Exposure (dB(A))
eq
(NIPTS for Combined Exposure)
Motorcycle
Exposure Non-
over an Motorcycle
Annual Hours of Motorcycle Operation
Operational
Cycle (Leg)
100
100
100
95
95
95
90
90
90
Exposure
(Leq)
80
70
60
80
70
60
80
70
60
0
80 (2.5)
70 (0.0)
60 (0.0)
80 (2.5)
70 (0.0)
60 (0.0)
80 (2.5)
70 (0.0)
60 (0.0),
50
82.3 (3.8)
79.0 (2.0)
78.5 (1.8)
80.9 (3.0)
75.1 (0.7)
73.6 (0.3)
80.3 (2.7)
72.3 (0.1)
69.0 (0.0)
100
83.8 (4.8)
81.8 (3.5)
81.5 (3.3)
81.6 (3.4)
77.3 (1.3)
76.6 (1.1)
80.6 (2.8)
73.8 (0.4)
71.8 (0.1)
200
85.2 (5.8)
87.8 (7.9)
83.6 (4.6)
82.4 (3.8)
79.2 (2.1)
78.7 (1.9)
80.9 (3.0)
75.2 (0.7)
73.8 (0.4)
400
87.5 (7.7)
86.6 (6.9)
86.6 (6.9)
83.9 (4.8)
81.9 (3.5)
81.7 (3.4)
81.6 (3.4)
77.4 (1.4)
76.6 (1.1)
5-82
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REFERENCES
1. Environmental Impact Statement for Proposed Noise Abatement
Regulations, Noise Section, Department of Ecology, State of
Washington, Olympia, WN 98504, 16 April 1975.
2. Motor Vehicle Noise Identification and Analysis of Situations
Contributing to Annoyance, Bolt Beranek and Newman, Inc., Report
2082, June 1971.
3. Michael, J. J., "Research Briefs: A Final Summary of Attitudes of
Senior Land and Recreation Managers in the United States Regarding
Off-Road Recreation Vehicles," Parks and Recreation, 8(2):39-41,
February 1973.
4. Shepherd, K. P., A Preliminary Study of the Annoyance Due to Noise
From Recreational Vehicles, Laboratory for Hearing Studies and
Noise Control, University of Utah, Report T.R. 75-001, 1975.
5. Evaluation of Stationary and Moving Motorcycle Noise Test Methods
For Use in Proposed Regulations, McDonnell Douglas Astronautics
Company-West, Huntington Beach, California 92647, Report A3-13E-
469, December 1975.
6. Survey of Motorcycle Ownership, Usage and Maintanence, a Gallup
Organization, Inc. survey conducted for the Motorcycle Industry
Council, Inc., Report GO 7458, January 1975.
7. Chicago Urban Noise Study, Bolt Beranek and Newman, Inc., Cambridge,
MA, Report No. 1411, 1971.
8. Palka, P., private communication, Motorcycle Industry Council,
Inc., July 1976.
9. Gary, Richard F., A Survey of Light Vehicle Operations, Noise and
Vibration Laboratory, General Motors Proving Ground, Milford, MI
48042, Engineering Publication 6313, July 1975.
10. Certification and Test Procedures for New Motorcycles, Emission
Regulations and Appendices, Federal Register, Jan. 5, 1977.
11. County and j:ity Data Book 1972, U.S. Department of Commerce, Social
and Economic Statistics Administration, Bureau of the Census,
pp. xiv and 590-613.
12. Information on Levels of Environmental Noise Requisite to Protect
Public Health and Welfare with an Adequate Margin of Safety, U.S.
Environmental Protection Agency/ Washington, D.C. 20460, 550/9-74-
004, March 1974.
5-83
-------
13. Public Health and Welfare Criteria for Noise, U.S. Environmental
Protection Agency, Washington, D.C. 20460, 550/9-73-002, July 27,
1973.
14. Galloway, W. J., et al, Population Distribution of the United States
as a Function of Outdoor Noise Level, U.S. Environmental Protection
Agency, Washington, D.C. 20460, 550/9-74-009, June 1974.
15. "Paying to Pollute," Organization for Economic Co-operation and
Development, Environment, Vol. 18, No. 5, June 1976.
16. Harrison, R. T., Sound Propagation and Annoyance Under Forest
Conditions, U.S. Department of Agriculture, Forest Service, San Dimas
Equipment Development Center, San Dimas, CA 91773, Report 7120-6,
March 1974.
17. Nelson, P. M., et al, Predicting Road Traffic Noise in the Rural
Environment; A Study of the A66 Road Improvement Scheme in the
Lake District, Transport and Road Research Laboratory, Crowthorne,
Berkshire, England, TTRL Laboratory Report 642 (NTIS PB-239-187),
1974.
18. Harrison, R., The Effectiveness of Motorcycle Helmets as Hearing
Protectors, U.S. Department of Agriculture, Forest Service, Equip-
ment Development Center, San Dimas, CA 91773, Report ED&T 2210,
September 1973.
19. Lukas, J. S., Measures of Noise Level; Their Relative Accuracy in
Predicting Objective and Subjective Responses to Noise During Sleep,
U.S. Environmental Protection Agency, Washington, D.C. 20460,
6001 1-77-010, February, 1977.
20. Mills, C. H. G. and D. W. Robinson, "Appendix IX—The Subjective
Rating of Motor Vehicle Noise," Noise—Final Report, presented to
Parliament by the Lord President of the Council and Minister for
Science by Command of Her Majesty, July 1963, Her Majesty's
Stationery Office, London (reprinted 1973) Cmnd 1056.
21. Harrison, R., Development of a Noise Standard for the Oregon Dunes
National Recreation Area, U.S. Department of Agriculture, Forest
Service Equipment Development Center, San Dimas, CA 91773, July
1973.
22. Harrison, R. T., Off-Road Vehicle Noise-Effects on Operators and
Bystanders, Forest Service, U.S. Department of Agriculture. Re-
port 740687 prepared for Society of Automotive Engineers, National
Combined Farm, Construction and Industrial Machinery and Power-
plant Meetings, Milwaukee, WI, September 9-12, 1974.
5-84
-------
23. Fidell, S., K. S. Persons and R. L. Bennett, Predicting Aural
Detectability of Aircraft in Noise Backgrounds, Bolt Beranek and
Newman, Inc., Cambridge, MA, Report 220-AFFDL-TR-72-17, July 1975.
24. Harrison, R. T., Impact of Off-Road Vehicle Noise on a National
Forest, U.S. Department of Agriculture, Forest Service, Equipment
Development Center, San Dimas, CA 91773, Report ED&T 2428, July
1975.
25. System Considerations for Urban Arterial Streets, ITE Information
Report, Institute of Traffic Engineers, 2029 K Street NW, Washing-
ton, B.C. 20006, October 1969.
26. California Highway Patrol Noise Team Enforcement Survey (Statistics
Sheet), Annual, California Highway Patrol, Sacramento, CA, 1975.
27. 1973/74 Automobile Facts and Figures, Motor Vehicle Manufacturers
Association, Detroit, Michigan 48202.
28. Statistical Abstract of the United States, 1975, U.S. Department
of Commerce, Bureau of the Census, 96th Annual Edition.
29. Background Document for Medium and Heavy Truck Noise Emission
Regulations, U.S. Environmental Protection Agency, Washington, D.C.
20460, EPA-550/9-76-008, March 1976.
30. Gunn, W. T., Shighebisa, and W. Shepherd, Relative Effectiveness of
Several Similated Jet Engine Noise Spectral Treatments in Reducing
Annoyance in a TV-viewing Situation, NASA Langley Research Center,
Draft Report, 1976.
31. Sutherland, L., M. Braden, and R. Lolman, "A Program for the Mea-
surement of Environmental Noise in the Community and its Associated
Human Response, Volume 1," Wyle Research Report WR-73-8 for the
U.S. Department of Transportation, December 1973.
32. Welch, B. L. and Welch, A. S. (Editors), "Physiological Effects of
Noise." Plenum Press, New York, 1970.
33. Report in preparation on community attitudes to noise in Boulder,
Colorado, EPA regional office, Denver, Colorado.
34. Rackl, R., Sutherland, L.C., and Swing, J., "Community Noise Counter-
measures Cost-Effectiveness Analysis," Wyle Research Report No. WCR
75-2, prepared for the Motor Vehicle Manufacturers Association, July,
1975.
35. Plotkin, K., "Assessment of Noise at Community Development Sites.
Appendix A—Noise Models." Wyle Research Report WR 75-6. October
1975.
5-85
-------
36. Harrison, R.r private communication, U.S.D.A. Forest Service,
October 1976.
37. Gourdin, D., Boulder Community Noise Program Attitudinal Survey,
Environmental Protection Agency, Boulder, Co.
38. Lukas, J.S., Noise and sleep: a literature review and a proposed
criterion for assessing effects. The Journal of the Acoustical
Society of America, 58(6), 1232-1242, 1975.
39. Environmental and Economic Impact Statement, Exhaust and Crankage
Regulations for Motorcycles, Environmental Protection Agency,
January, 1977.
40. Skipton, Leonard and Paul N. Borsky, A Causal Model for Relating
Noise Exposure. Psychosocial Variables and Aircraft Noise Annoyance,
Preceedings of the International Congress on Noise as a Public Health
Problem, Dubrovnik, Yugoslavia. EPA Report No. 55019-73-008. May
13-18, 1973.
41. Guidelines for Preparing Environmental Impact Statements on Noise.
Committee on Hearing, Bioacoustics and Biomechanics/ Report of
Working Group 69, National Research Council, 1977.
42. House Noise—Reduction Measurements for use in Studies of Aircraft
Noise, SAE Report AIR 1081, October 1971.
5-86
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SECTION 6
SOUND REDUCTION TECHNOLOGY
-------
Section 6
SOUND REDUCTION TECHNOLOGY
6.1 Diagnostic Evaluation of Sound Sources
Many of the manufacturers which EPA and its motorcycle technology
contractor visited have performed and/or sponsored comprehensive diagnostic
studies on motorcycle sound source contributions/ and have defined the
major sound-producing components and the levels of sound produced by these
component sources both singly and in combination. The diagnostic techniques
employed for identification of sound source contributions, and the specific
sound control methods being employed or studied by the different manufac-
turers, were presented to the EPA on a confidential basis.* Table 6-1 shows
the relative contribution of these sources for 21 1976 model motorcycles
(as determined by the manufacturer of the vehicle), in three groupings:
exhaust, intake, and mechanical. In this listing, "mechanical" encompasses
sound radiated by the engine, power train, frame structure and equipment
carried on the frame, and also tire and wind noise, the latter two being
generally insignificant at current total vehicle sound levels. The vehicles
are listed in descending order of total -sound level (as measured by the
J331a test); perusal of the table shows that the distribution of noise
source contribution varies widely, and is independent of total sound level,
use category, and engine type. There is also no relationship or trend
between engine displacement and source contribution.
The sound reduction techniques necessary to meet a particular
emission standard will vary widely from motorcycle to motorcycle, and
are very difficult to place in a generally-applicable matrix of vehicle
category/subcategory vs. sound level. For example (referring to the Table),
to reduce sound emissions of vehicle "D" currently at 83 dBA to 80 dBA
would require attention primarily to the exhaust which is contributing
84% of the sound; this might be attained relatively easily. On the other
hand, for vehicle "H", currently at 82 dBA, the attainment of an 80 dBA
level would require quieting the mechanical sources, which might consti-
tute a major engineering effort.
*Most data was supplied by: Honda, Yamaha, Kawasaki, Suzuki and Barley-
Davidson. Otner manufacturers visited also supplied data used in this
analysis.
6-1
-------
TABLE 6-1
NOISE SOURCE CONTRIBUTION, 1976 MODEL MOTORCYCLES
Total
Category
% Contribution of Noise Source
Vehicle Vehicle
Sound
Level
dBA
84
83
83
83
82.5
82
82
82
82
81
80.5
80
80
80
80
79.5
79.5
79.5
79
77.5
77
*"Mechanical
equipment.
Ref.
Letter
A
B
C
D
E
P
G
H
I
J
K
L
M
N
0
P
Q
R
S
T
U
Use
S
S
S
SX
S
S
S
S
S
S
SX
S
SX
SX
SX
S
SX
S
S
S
SX
Eng. Type
4S
4S
2S
2S
4S
4S
2S
2S
2S
2S
2S
4S
4S
2S
2S
4S
2S
4S
4S
4S
4S
" includes engine, transmission,
tires and wind noise.
Exhaust
60
35
24
84
47
30
24
6
6
11
28
10
28
51
33
25
1
32
26
66
42
Intake Mechanical*
3
55
30
5
6
35
38
4
63
50
31
64
18
16
30
18
79
35
20
20
22
37
10
46
11
48
35
38
90
31
39
41
26
54
33
37
57
20
33
54
14
36
chain, frame, ancillary
6-2
-------
6.2 Sound Reduction Technology
A review of the techniques which are in use or which can be
selectively used to quiet motorcycles is presented in this section. No
consideration is given to cost, nor to the suitability of these various
techniques in relation to functional or aesthetic criteria.
Exhaust system quieting methods
Near term control of motorcycle sound emissions centers around the
exhaust system, air intake system, and the mechanical/drive components.
In approaching the sound reduction problem, manufacturers generally treat
the exhaust and intake noise sources first because modification of these
sources generally impact the basic model configuration least.
Exhaust noise is generally reduced by using one or more of the
following techniques: increasing muffler volume, adding reactive chambers/
tubes, adding absorptive materials, restricting exhaust flow by baffles or
perforated tubes, and dampening, stiffening, or isolating outer walls.
Muffler volume can be increased by: physically enlarging the shell; inter-
connecting header pipes on multi-cylinder motorcyles (e.g., 4 into 1, 4
into 2 type systems), adding cross-pipes between dual exhaust systems where
applicable, or combinations of these techniques. Interconnecting pipes
change the impulse frequencies of the muffler in a favorable direction
for improved effectiveness, but requires that reactive elements be properly
designed for the changed frequency spectrum. In many cases redesign and
modification of the muffler interior will reduce sound levels, generally
at some penalty in increased backpressure. Such techniques include adding/
modifying reactive chambers, adding or sealing baffles, modifying the core
pipe, inserting sound absorption lining arid retaining walls, revising/
constricting exhaust flow, and adding elastic components. Dampening of
the shell walls can be accomplished by use of laminated material, different
material, or application of semi-viscous coatings. Stiffening of the shell
walls can be accomplished by use of ribbing or internal bracing. Isolation
can be accomplished by mounting components on elastomer supports. The
latter modifications do not reduce sound emitted from the exhaust outlet,
but reduce radiated noise from the muffler shell.
Biese techniques can be summarized:
o Increase muffler volume
o Interconnect exhaust pipes
o Modify interior
o Add sound absorptive lining
6-3
-------
o Increase shell thickness/rigidity
o Construct double walls
o Isolate mounting
Application of these techniques is not at all straight-forward, and
is in reality a very complex design problem. As an example, motorcycles
with 2-stroke engines require optimally designed expansion chambers to
assure proper exhaust scavenging and charging of cylinders. Modification
of the exhaust system if improperly done could reduce performance drasti-
cally. Other modifications could create excessive back pressure, increase
weight and fuel consumption or reduce motorcycle lean angle, balance, or
ground clearance.
Intake system quieting methods
Air intake noise can be reduced by shielding or modifying the inlet
duct, restricting or lengthening the intake path, increasing shell volume,
adding baffles or absorptive materials, and dampening and/or isolating the
intake shell. Hie shell dampening can be accomplished by the use of thicker
or different material, reinforcement, or double wall construction. The
techniques used to control air intake systems can be summarized:
o Increase volume
o Modify inlet
o Modify interior
o Add sound absorption lining
o Increase wall thickness
o Construct double walls
o Shield inlet
o Reduce inlet area
Mechanical system quieting methods
The objective of mechanical redesign and rework is generally to
reduce or contain engine and drive interaction noise (i.e., piston slap,
valve clatter for 4-stroke models, gearing mesh, chain noise, etc.) and
to reduce vibration (resonance) noise. The effort can be minor or major,
depending on model peculiarities and degree of sound reduction required.
Various techniques currently in use and mentioned by manufacturers as
possibilities for future models are summarized as follows; and are
described in the following paragraphs:
6-4
-------
o Stiffen/dampen fins and case webs o Stiffen crankshaft
o Change fin shapes
o Thicken/reinforce components
o Inprove component mounting
o Thicken/reinforce case covers
o Isolate case covers
o Increase lubrication
o Modify piston/cylinder
o Reduce tolerances/improve finish
o Modify bearings
o Modify timing/drive belts/chains
o Modify camshaft
o Reduce valve clatter
o Increase flywheel mass
o Redesign clutch and
transmission
o Inprove chain tensioner
o Enclose drive chain
o Danpen/ioslate chain cover
o Stiffen/frame; isolate
engine
o Lower engine speed
o Reduce specific horsepower
o Liquid cooling
o Convert 2-stroke to
4-stroke engine
o Reconfigure engine to
reduce dynamic unbalance
forces
o Use hydraulic torque
converter
o Convert to shaft drive
o Enclose engine
Stiffen/dampen fins and webs—Insertion of elastomer pads or metal
dowels between radiating fins to reduce fin vibration.
Change fin shapes—modification or reinforcement of fins to reduce
vibration.
Thicken/reinforce components—Modification or reinforcement to
reduce vibration.
Improve component mounting—Use of gaskets and elastomer pads to
isolate components to reduce vibration through metal to metal contact.
Uiicken/reinforce case covers—Includes use of thicker material,
reinforcement ribbings or double covers on such elements as gear covers,
crankcase covers, camshaft covers and so forth.
6-5
-------
Isolate case covers—Use of elastomers to reduce vibration and
radiated noise.
Increase lubrication—Providing additional pressure lubrication to
reduce nechanical interaction noise.
Modify piston/cylinder—Modify piston/cylinder configuration to
reduce piston slap.
Reduce tolerances/improve finish—Reduce tolerances, or improve
finishes of gears, bearings and so forth to reduce mechanical interaction
noise.
Modify bearings—Replace ball and roller bearings with journal
type bearings to reduce mechanical interaction noise.
Modify timing/drive belts/chains—Convert from chain drives to
Hy-Vo, rubber or other types of quiet belts where applicable (e.g., timing
belt change applicable to overhead cam engines).
Modify camshaft—Modify cam shape and increase shaft rigidity to
reduce nechanical interaction noise.
Reduce valve clatter—Use of hydraulic lifters to eliminate tappet
clearance (where applicable); incorporate elastomers to cushion tappet
noise in overhead cam engines.
Increase flywheel mass—To reduce engine vibration.
Stiffen crankshaft—To increase rigidity and reduce mechanical
interaction noise.
Redesign clutch and transmission—Use of helical gears instead of
spur gears to reduce mechanical interaction noise; use of journal type
bearings.
Improve chain tensioner—To reduce chain/sprocket interaction noise
and chain tensioner noise.
Enclose drive chain—To attenuate drive chain noise.
Dampen/isolate chain cover—To eliminate cover vibration and
radiated noise.
Stiffen/dampen frame; isolate engine—To prevent radiated noise due
to engine vibration transmitted to the frame and to components mounted on
the frame.
6-6
-------
Lower engine speed—To reduce mechanical interaction noise.
Reduce specific horse power—To reduce the excitation forces which
result in engine noise radiation.
The above sound reduction techniques range from detail changes
to significant redesign. For some models reductions in mechanical/drive
sound levels to meet stringent sound standards would require techniques
involving complete redesign of the engine and drive train. In addition,
some of the techniques would result in reduced engine performance. As
discussed in Section 4.1, it is impossible to predict by product categories
which specific proposed regulatory levels will require major model changes.
The lowest levels that any of the manufacturers have reported as being
feasible for the near-term is 80 dBA for street motorcycles, 84 dBA for
off-road motorcycles. Other manufacturers question that an 80 dBA sound
standard can be met without major redesign on some models. Major model
configuration changes could include the use of such techniques as con-
version to liquid cooling, enclosing or covering the engine, conversion
from a 2-stroke to 4-stroke engine (where applicable); use of a hydraulic
torque converter for power transmission, conversion to shaft drive, engine
re-configuration to reduce unbalance forces, or any other major engine/
drive redesign not specified here. These techniques would all require
major changes in manufacturing operations, and extensive lead time. These
techniques, not necessarily feasible in all use categories, are discussed
in the following paragraphs.
Liquid Cooling—Liquid cooling, because it allows reduced clearances
in engine parts, and because it provides added shielding ardund the engine
cylinders, can materially reduce engine radiated noise. Conversion to
liquid cooling would require re-engineering and re-tooling of the engine,
add significant weight, and add to unit manufacturing costs. Additional
hardware is required to implement liquid cooling, including a pump, radi-
ator, thermostat, coolant, plumbing, instrumentation and recasting of
the cylinder head and walls. Feasibility of liquid cooling for off-road
motorcycles is very questionable because of vulnerability of the radiator
to damage from rocks and spills.
6-7
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4-Stroke vs. 2-Stroke Engines—Scare manufacturers feel that 4-strdke
engines are easier to quiet than 2-stroke engines. Because of this,
conversion of engine types is a potential option. This alternative is also
weighted by the fact that exhaust chemical emissions are more difficult to
control in two-stroke engines, a factor currently of great concern to many
manufacturers. It is unlikely that engine conversions would be made for
noise control alone, due to the considerable engineering development and
plant and equipment expenditures that would be required. In addition,
direct manufacturing unit costs of 4-stroke engines are estimated by
manufacturers to be more than those of equivalent sized 2-stroke engines.
Reduction of Unbalanced Forces—Unbalanced forces which cause engine
and frame vibration are more severe in some engine configurations than in
others. For example, unbalanced forces can be reduced by use of opposed
cylinders, counter-rotating crankshafts, or balanced "V" configurations.
Biese methods can involve dynamic vibration absorbers or counter-rotating
balancing elements.
Shaft Drive—Shaft drive is an option that would reduce drive train
noise on large (over 750cc) and possibly medium sized (450-749cc) on-road
motorcycles. Shaft drive on models intended for some off-road use is less
attractive, because of weight constraints and flexibility requirements in
the drive train that are required for these models. Shaft drive affects
many of the other components on the motorcycle, and is a relatively expen-
sive option. A more cost-effective method of reducing drive noise in most
cases would be to fully enclose the chain, which was identified previously
as a sound reduction measure.
Hydraulic Torque Converter—Another technique that would involve
major nodel configuration change is converting from a standard transmission
to a hydraulic torque converter and a hydraulic gear engagement clutch, as
exemplified by the transmission on the Honda CB 750A. Torque conversion by
hydraulic means is basically quieter than by gears.
Engine Enclosure—Manufacturers indicated that if engine enclosure
is considered as a noise control measure, it would generally be used in
conjunction with liquid cooling. Enclosure or covering of air-cooled
engines could create significant engine temperature control problems. In
addition, some of the manufacturers feared that enclosure could drastically
affect the marketability of motorcycles, since styling is an important
factor affecting demand for motorcycles. Engine enclosure would entail
added weight, and could hamper access for servicing.
6-8
-------
Although there is no generally-applicable set of techniques
that will achieve specified regulatory levels for a specific motorcycle,
a matrix of techniques based on manufacturer-supplied information was
developed for costing purposes. This matrix is presented in Table 6-2.
For each regulatory level below 83 dB(A)f a schedule of techniques other
than major model changes are shown for each product class. Manufacturer
information generally indicates that all techniques discussed above would
be necessary to achieve a 75 dB(A) level for models above 170c.c. Fewer of
these techniques, or less extensive use of these techniques, are expected
to be necessary at higher levels. For costing purposes two estimates were
made at each study level below 83 dB(A): one assuming no major model change
necessary, and one assuming a major model change. As shown, the major model
change assummed for street motorcycles is the use of liquid cooling. For
off-road motorcycles, conversion to 4-stroke engines is assumed. Different
individual models will of course require major model changes at different
regulatory levels. A few are expected to require them at an 80 dB(A) level,
a substantial number are expected to need them at 78 dB(A), and virtually
all are expected to need them at a 75 dB(A) level. This is discussed in
more detail in Section 7.
6-9
-------
TABLE 6-2
SOUND REDUCTION TREATMENTS ASSUMED FOR EACH STODY tEVEL
(J331a - NOT-TO-EXCEED BASIS)
EXHAUST SYSTEM
INCREASE MUFFLER VQUME
CROSS CONNECTIONS
MODIFY INTERIOR
SOUND ABSORPTIVE LINING
INCREASE SHELL THICKNESS
DOUBLE MALLS
AIR INTAKE SYSTBi
INCREASE VOLUME
MODIFY INLET
MODIFY INTERIOR
SOUND ABSORPTIVE LINING
INCREASE MALL THICKNESS
MECHANICAL/DRIVE SYSTEM
STIFFEN/DAMPEN FINS/WEDS
IMPROVED COMPONENT MOUNTING
THICKEN/REINFORCE CASE COVERS
INCREASE LUBRICATION
MODIFY PISTON/CYLINDER
REDUCE TOLERANCES/IMPROVE FINISH
MODIFY BEARINGS
MODIFY TIMING/DRIVE BELTS/CHAINS
REDUCE VALVE CLATTER (4 STROKE)
INCREASE FLYWHEEL MASS
MODIFY CRANKSHAFT/CAMSHAFT
MODIFY GEARS/TRANSMISSION
TIGHTEN CHAIN
ENCLOSE CHAIN
MODIFY FRAME
750 + c.c. 350 - 749 c.c.
63 80 78 75 S3 80 76 75
170 - 349 c.C.
83 80 78 75
X X X X
X X X X
X X X X
XXX
XXX
X
X X X X
X X X X
X X X X
XXX
XXX
X
X X X X
X X X X
X X X X
XXX
X X
100 - 169 c.c.
83 80 78 75
XXX
X X X X
X X X X
X X
X X
100 c.c.
83 flfl Tfl 75
XXX
XXX
X X
X X
X X
X
X
X
X X
X X
X X
X X
X X
X X
X X
X
X
X
X X
X X
X X
X X
X X
X
X
X X
X X
X X
X X
X X
X
X
X
X
X
X
X X
X
X
X
X
X
X
X
X
X
X
X X
X X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X X
X X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
XXX
XXX
XXX
x x
X X
X X
X X
X
X X
X
X
X
X
X X
X X
X X
X
X
X X
X
X
-------
6.3 Impacts of Sound Reduction Technology
6.3.1 Performance Inpacts
Each of the techniques cited above can have impacts on motorcycle
performance characteristics. Engine horsepower (including width of power
band), torque, weight, lean angle, center of gravity, ground clearance
and suspension characteristics can all be affected.
Power
All manufacturers cited engine power losses resulting from achieving
current sound levels. Increasing power loss is expected at the lower levels
studied. The power loss is generally attributable to restricted air intake
and exhaust system back pressure. Table 6-3 indicates some of the data
submitted to EPA pertaining to power losses involved in achieving current
sound levels. From these data it is apparent that additional sound reduc-
tion measures will result in further power losses. Liquid cooling,
with its potential for decreased engine tolerances, can abate this trend
somewhat. Conversion from 2-stroke to 4-stroke engines will result in
additional specific horsepower loss.
Weight
Many of the techniques cited may -cause additional weight penalities.
Modifications to the exhaust system could result in doubling current muffler
weight or more, although the increasing use of 2 into 1, 3 into 1 and 4
into 1 exhaust systems on multicylinder motorcycles could abate this con-
siderably. Similarly, more complex air intake systems might be expected
to weigh more than current systems by factors of two or more. Mechanical
noise quieting can be achieved through the use of thicker covers, improved
mounting and increased mass of moving parts. The combination of these
measures could increase engine weight by 10 to 15%. In addition, major
engine modifications can result in a significant vehicle weight increase.
One manufacturer estimated an increase of 10% in vehicle weight for liquid
cooling (about 50 lb. for large motorcycles). Conversion of single cyclinder
2-stroke engines to single-cyclinder 4-stroke engines could cause an increase
of up to 30% in total engine weight. Shaft drive mechanisms are quite heavy,
but the lighter and less costly alternative of enclosure of the final drive
chain will be assumed for the assessment of weight penalty.
6-11
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Table 6-3
POWER LOSS ASSOCIATED WITH
ACHIEVING CURRENT LEVELS
Motorcycle
a
b
c
d
e
f
g
h
•
k
1
m
Sound Level
Reduction (dB)
4
4
2
2
0.6
2
2
2.5
1.6
3.5
1
8
6 (approx)
Power Loss
12% over 6,000 RPM
2%
30%
30%
3%
1%
3%
28%
1%
10%
6%
up to 28%, 10% at peak
12-15% (peak; very little
below 4,000 RPM,
severe roll off
past peak)
SOURCE: Confidential Manufacturer Data
6-12
-------
6.3.2 Operation Inpacts
The only significant impact of sound level reduction on operation
costs should be a reduction in fuel economy. Increased weight, increased
back pressure, power loss, and power required to drive auxiliary equipment
(e.g., radiator pump) may all exact a fuel consurrption penalty.
It should be noted, however, that conversion from 2-stroke to
4-stroke engines could be expected to reverse this trend somewhat due to
the slightly better fuel efficiency of 4-stroke engines.
From the previous section, the following vehicle weight increases
are assumed (as a fraction of total vehicle weight):
Regulatory Level
Over 170c.c. 86dB 83dB 80dB 78dB 75dB
Street: Straight forward change 0 2% 5% 10%
Major model change - 10% 15% 20%
Off-Road: Straight forward change 0 2% 5% 10% -
Major model change - 10% 15% 20%
100-169c.c.: One-half of above figures
Less than lOOc.c.: 0% at all levels
Manufacturers supplied very little data on fuel economy impacts
of achieving current or future sound levels. The little data that was
furnished indicated that the 3 to 4 dB reductions to achieve current levels
resulted in up-to-15% loss in fuel economy, although some models showed no
change or an improvement. Experience with trucks and automobiles indicates
that a 10% decrease in fuel economy for a 10% weight increase is a good
assumption, but one which may tend to overstate the fuel economy penalty.
Using this assumption, however, the above table can also serve to indicate
the assumed fuel economy losses at the various regulatory levels when
backpressure and other penalties are included.
6.3.3 Maintenance Impacts
Several of the quieting techniques cited either require additional
maintenance or make currently required maintenance somewhat more costly or
more time consuming. Principal among the first of these are the minimal
attention needed to keep a liquid cooling system in working order, and
the additional maintenance associated with a switch from 2-stroke to
4-stroke engines. Complex mounting techniques, additional covers, reduced
engine tolerances, valve train complexities and enclosed final drive will
complicate routine maintenance. No definitive data on the maintenance
6-13
-------
impacts of these techniques are available. For the pusposes of analysis
the following additional annual maintenance time (in hours) is assumed:
Regulatory Level
Over 170c.c. 86dB 83dB 80dB 78dB 75dB
Street: Straight forward change - 0 1/4 3/8 1/2
Major model change - - 3/4 7/8 1
Off-Road: Straight forward change 0 1/4 3/8 1/2 —
Major model change - 3/4 7/8 1 —
100-170c.c.: One-half of above figures
Under lOOc.c.: Zero at all levels
Sound reduction will affect cost of maintenance and replacement
parts only through increased cost for replacement exhaust systems.
6.3.4 Aesthetic Factors
To many motorcyclists the aesthetic impacts of sound reduction
technology may be even more important than performance or cost inpacts.
Many of the above techniques can be expected to have an adverse impact
on the sleek and sporty styling of current models. Larger mufflers,
frame reconfigurations to accomodate larger air intake systems, bulkier
engines and liquid cooling all pose styling problems. Although these
factors are unquantifiable, they are felt to have potential sales impacts
independent of the cost and performance factors cited above.
6.4 Production Variations
The sound levels of all nominally identical surface transpor-
tation products exhibit a distribution covering a range of several
decibels. Since EPA's regulations are on a not-to-exceed basis,
manufacturer design and production must account for this distribution
of sound levels to assure compliance with the standards. This is in
addition, of course, to factors accounting for testing variables.
Manufacturers supplied EPA with data on the production variation exhibited
by certain of their models. These data are displayed in Table 6-4.
From these data it is concluded that manufacturers will have to produce
vehicles at least 1 l/2dB below an applicable standard to account for
production variations.
6-14
-------
Table 6-4
PRODUCTION VARIATION
Manufacturer Production Variation (dB)
a 20*= 3-4
b 1.5 - 2.5
c l*= 0.25 - 0.6
d 2-stroke: 1.5
4-stroke: 2.0
e 1.5
SOURCE: Manufacturer Confidential Data
6-15
-------
6.5 "Best Available Technology"
Each of the quieting techniques discussed in Section 6.2 exist
either in current production models or in prototypes in advanced states
of development. As such, their combined use represents "best available
technology" for motorcycles. Large and complex exhaust and intake systems
have been demonstrated on a wide variety of production vehicles. Weight,
positioning, and performance penalties are the only technological limits
to larger and more complex units. There are numerous examples of current
motorcycles either with large muffler volume in relation to engine
displacement or sophisticated muffling of multicyclinder engines. Double-
wrapped mufflers have been used in several models and prototypes, and at
least one prototype known to EPA uses a major engine frame member for its
air intake reservoir.
Many of the engine quieting techniques discussed previously exist
in current production engines. Recent models from the major manufacturers
have demonstrated significantly reduced engine mechanical noise. Balanced
(90-degree) V-twin engines have been well demonstrated.
The past five years of motorcycle development has seen an
increasing number of multi-cylinder engines with high specific horsepower.
This specific horsepower has often been achieved by increased engine speed,
which has resulted in increased engine mechanical noise. The testing pro-
gram data base shows the critical importance of engine speed to engine noise.
Decreased engine speed at a loss of specific horsepower is available to all
manufacturers of high RPM engines.
Liquid cooling has been well demonstrated on several production
models, both 2-stroke and 4-stroke. Liquid cooling for a complete line of
smaller 2-stroke motorcycles (down to SOc.c.) has been demonstrated by one
European manufacturer.
Shaft-drive has been well demonstrated on motorcycles 500 c.c. and
above.
Based on an examination of motorcycle models incorporating the
techniques discussed above, EPA has concluded that the 78 dB(A) regulatory
level (J-331a), requiring a 75 dB(A) design level, is the level representa-
tive of "best available technology" for street motorcycles in the meaning
of the Noise Control Act. The Honda GL-1000, generally acknowledged to
be the quietest large motorcycle ever produced, already incorporates many
of the major techniques listed above (liquid cooling, shaft drive, very
large intake and exhaust systems). Even this motorcycle would require
some small additional quieting to meet a 78 dB(A) level on a production
basis.
6-16
-------
Lower levels could be achieved with the probable elimination of
many large motorcycles and many smaller 2-stroke motorcycles. Although
four-stroke motorcycles in the smaller displacement classes would un-
doubtedly be able to achieve a 75dB(A) (J-331a) regulatory level (requiring
a 72dB(A) design level) EPA has concluded that this limited class of
vehicles does not represent "best available technology" in the meaning of
the Act.
"Best available technology" for off-road motorcycles is a question'
both of technology and performance. Although motorcycles with off-road
capability can be built at levels almost as low as for street motorcycles,
such motorcycles demonstrate significant performance penalties. Weight,
power, power band width and ground clearance are all of crucial importance
to off-road motorcycles. Each of these factors on an off-road motorcycle
can be more significantly impacted at lower sound levels than for street
motorcycles of comparable displacement. The inappropriateness of applying
liquid cooling to off-road motorcycles leads to different levels of "best
abailable technology" for large and small off-road motorcycles. Small
off-road motorcycles (under 170c.c.) are expected to be able to achieve
the same levels achievable by their street counterparts. Large off-road
motorcycles, however, without the option of liquid cooling cannot achieve
the same levels as their street counterparts (exacerbated by the fact that
most street motorcycles over 170c.c. have multi-cylipder engines, whereas
off-road motorcycles must be single cylinder). Manufacturers indicated
that given enough lead time, an 83 dB(A) regulatory level might be achiev-
able with large 2-stroke off-road motorcycles. They were unanimous,
however, in stating that .the 80 dB(A) regulatory level would require
4-stroke engines for most large models. Since liquid cooling is not
viable for off-road motorcycles, EPA has concluded that this 80 dB(A)
regulatory level constitutes "best available technology" for this class
of off-road motorcycles. It is understood that although these levels are
achievable, the performance of large 4-stroke off-road motorcycles will be
inferior to current models, significantly so in many cases.
Although all of the techniques constituting "best available
technology" exist in production or prototype motorcycles, not all manu-
facturers have the capability of incorporating them into their motorcycles.
Particular problems exist with manufacturers that have uniquely identifiable
engine types that can be fundamentally changed only with a serious iirpact
on marketing position (Barley-Davidson, BMW, Moto Guzzi, Ducati),, manufac-
turers whose products have been developed from racing motorcycles and depend
on high performance (Laverda, MV Agusta), smaller manufacturers of high-
performance off-road motorcycles (Can-Am, Husqvarna, Bultaco, etc.) and
small manufacturers without large R&D capability (PT Motorcycles, Rokon,
other very small U.S. manufacturers).
6-17
-------
6.6 Lead Tiroes
In the absence of certification for air emissions, manufacturers
generally indicated the following lead times were necessary to make changes
on an individual motorcycle model (total time, drawing to production):
Changes to exhaust or air intake system that do not require frame or engine
redesign—one year; changes requiring frame redesign or minor engine re-
design—two to three years; major engine redesign—four to five years;
new engine model, new engine concept, conversion to 4-stroke engine—five
to six years (and up). Limited R&D resources, however, allow redesign of
only a few models per year. Major manufacturers with extensive product
lines would require additional time to be able to redesign models on a
more or less orderly basis. In addition, air emission certification can
add one half to one year to required lead times for major manufacturers
due to required durability runs. Manufacturers emphasized the need to
coordinate effective dates of these regulations to eliminate unnecessary
recertif ication for air emissions when redesign for noise purposes takes
place.
Based on this information the following lead times are felt to be
achievable by major manufacturers, consistent with orderly redesign of an
extensive product line (years from promulgation):
Regulatory Level (J-331a)
86 83 80 78 75
Street: Straight forward change — 12 46
Major model change — — 4 6 10
Off-Road: Straight forward change 124 6 —
Major model change — 46 10 —
An accelerated schedule of lead times can be considered which
would require simultaneous redesign of many models. Manufacturers insisted
that resources were unavailable for orderly redesign on this basis. The
following is an "accelerated" schedule of lead times which might be achiev-
able at considerably increased R&D costs:
Regulatory Level (J-331a)
86 83 80 78 75
Street: Straight forward change — — 135
Major model change — — 357
Off-Road: Straight forward change 1235 —
Major model change — 357 —
6-18
-------
Different manufacturers, of course, have different lead time
requirements. Sound levels of current models (particularly the mechanical
contributions), available funds for R&D, size of product line, and famil-
iarity with 4-stroke or liquid cooling technology, all have a bearing on
individual lead time requirements. The "normal" lead time schedule cited
above is most appropriate for the major Japanese manufacturers other than
Honda. The sound levels of Honda's current product line would probably
allow somewhat shorter times. Barley-Davidson, Can-Am and the European
manufacturers wpuld all be severely tested to meet the same time schedule
as the major Japanese manufacturers, for a variety of reasons relating to
unique engine designs, exclusive use of 2-stroke engines or company size
(availability of R&D capital). If these other manufacturers would be
strained at the "normal" schedule, it is reasonable to conclude that they
would probably not be able to comply with the "accelerated" schedule.
6.7 Deterioration of Motorcycle Sound Levels
Most manufacturers supplied limited data on experience with
motorcycle sound levels during mileage and time accumulation. Several
engineering reasons were discussed as to why motorcycle sound levels
ought to decrease with usage, at least at first. After the initial break-
in period, mechanical interaction noise can abate as parts fit together
better. Muffler noise can decrease as carbon build-up seals small openings
left from the manufacturing process.
Properly designed all-metal mufflers can last a considerable period
of time before sound level deterioration occurs, depending on climate and
operating conditions. Properly designed mufflers with glass inserts can
also last a significant length of time, although poorly designed ones can
deteriorate rapidly. European standards make a distinction between
mufflers that direct exhaust gases through fibrous material and mufflers
that reflect exhaust gases into but not through the fibrous elements.
Some manufacturers specify replacement of fibrous elements or replacement
of the exhaust system when deterioration occurs. At least one manufacturer
supplies free replacement fiberglass for his mufflers.
In general, manufacturers supplied no engineering reasons why a
properly maintained and operated motorcycle should experience significant
sound emission deterioration over its lifetime. "Properly maintained" in
this context means replacement of parts (including such major parts as
mufflers) as needed according to the operation instruction. Deterioration
data for a few models is displayed in Table 6-5.
6-19
-------
Table 6-5
DETERIORATION OF MOTORCYCLE SOUND LEVELS
Model Deterioration (dB) Mileage
a
b
c
d
e
f
g-k (muffler only,
5 models)
1
m
2-4
+1
+1 1/2
+1 (peak +2)
-0-
right side: 0
left side: +1
-0.33* to -1.6/6,250 mi
-1 1/2 (+1; -1/2)
-1 V2 (±1/2)
10,000
6,250
6,250
6,250
6,250
6,250
6,250
up to 19,000
7,160
3,240
A negative number indicates a reduction in sound level
SOURCE: Manufacturer Confidential Data
6-20
-------
6.8 Relationship to Air Emission Control
A lumber of manufacturers expressed serious concerns that at
strict levels of air emission controls there may be a significant trade-
off between air pollution control and noise control. At the levels
established in EPA's final rule on motorcycle air emissions this concern
has abated somewhat.
The higher temperatures of exhaust gases due to air emission control
may have a dual effect on exhaust noise emissions. Higher temperature gas
is less dense, requiring a higher rate of flow for equivalent performance.
In addition, the higher temperature gas has more inherent energy which must
be dissipated. Both of these effects would tend to raise exhaust noise.
One manufacturer cited a study on automotive air emission and noise control
which showed sound level increases of 'up to 4 dB at strict levels of
emissions control.
A second effect of higher engine temperatures is the need for
larger surface areas to dissipate heat from an air cooled engine. These
larger surfaces, in turn, can increase sound radiation. Liquid cooling,
of course, would in large part counteract the higher engine and exhaust
temperature increases due to air emission control.
One manufacturer indicated that the increased length and complexity
of an air intake path could cause fluctuations in air/fuel mixture with a
corresponding adverse impact on air emissions.
6.9 Technology to Achieve Sound Levels
Based on Different Measurement Methodologies
Technology and costing information supplied to EPA by manufacturers
and developed by EPA contractors have been based on study levels specified
in terms of the J-331a test procedures. As discussed in Section 3, the
F-76a test procedure is felt to be statistically equivalent to J-331a
across a broad range of motorcycles although individual models may vary
up or down by several dB(A). The manufacturer-supplied information was
based on several models of each of the manufacturer's lines. The J-331a
and F-76a sound levels of each of the models used for these purposes were
compared to determine whether these vehicles represented anomolous cases
in the J-331a/F-76a relationship. Of 15 models used for technology and
costing purposes, ten showed differentials of less than 2 dB(A), one showed
a differential of 2 dB(A), anf four showed differentials of 3 dB(A). How-
ever, the models displaying differentials of 2 dB(A) or greater showed no
consistent pattern with as many higher under one procedure as the other.
The cost information in the succeeding chapters was checked carefully and
it was found that overall values do not change significantly as a study
level specified in terms of J-331a is translated into a study level speci-
fied in terms of F-76a.
6-21
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SECTION 7
COSTS OF COMPLIANCE
-------
Section 7
COSTS OF COMPLIANCE
7.1 Unit Cost Increases
7.1.1 Manufacturer Estimates for Specific Models
Each major manufacturer supplied EPA with estimates of
manufacturing unit cost increases for specific models to meet specified
study levels (not-to-exceed basis). Ihe manufacturer data was based
on the J-331a and CHP procedures. Manufacturers generally cited the
techniques summarized in Table 7-1 as the ones necessary to meet the
lower study levels. The major model distinctions were made by the manu-
facturers. Each manufacturer emphasized that most estimates at the lower
levels were based on engineering judgment alone, an
-------
TABLE 7-1
NOISE CONTROL TECHNIQUES
EXHAUST SYSTEM
AIR INTAKE
SYSTEM
MECHANICAL/DRIVE
SYSTEM
MAJOR MODEL CONFIGURATION
CHANGES (REPRESENTATIVE
INCREASE MUFFLER VOLUME
CROSS CONNECTION
MODIFY INTERIOR
SOUND ABSORPTION LINING
INCREASE SHELL THICKNESS
CONSTRUCT DOUBLE WALLS
ISOLATION MOUNTING
INCREASE VOLUME
MODIFY INLET
MODIFY INTERIOR
ADD SOUND ABSORPTION LINING
INCREASE WALL THICKNESS
DOUBLE WALLS
SHIELD INLET
REDUCE INLET AREA
STIFFEN/DAMPEN FINS AND WEBS
CHANGE FIN SHAPES
COMPONENT MOUNTING
THICKEN/REINFORCE CASE COVERS
INCREASE LUBRICATION
MODIFY PISTON/CYLINDER
REDUCE TOLERANCES/IMPROVE FINISH
MODIFY BEARINGS
MODIFY TIMING/DRIVE BELTS/CHAINS
REDUCE VALUE CLATTER (4-Stroke)
INCREASE FLYWHEEL MASS
MODIFY CRANKSHAFT/CAMSHAFT
MODIFY CLUTCH
MODIFY GEARS/TRANSMISSION
TIGHTEN DRIVE CHAIN
ENCLOSE DRIVE CHAIN
MODIFY FRAME
ISOLATE CHAIN COVER
LOWER ENGINE SPEED
REDUCE SPECIFIC HORSEPOWER
CONVERT 2-STROKE TO 4-STROKE
LIQUID COOLING
ADD HYDRAULIC TORQUE CONVERTER
CONVERT TO SHAFT DRIVE
ENCLOSE/COVER ENGINE
7-2
-------
*750cc AND ABOVE
!
I
280
D
( )
t/1
' •
• >
a
i
••
*350 - 749 cc
Above-/
750cc
Above 750cc
*350 - 749cc
*350 - 749 cc
*170 - 349 cc
*350 - 749 cc
*170 - 349 cc
2-STROKE
4-STROKE
*DENOTES MAJOR!
MODEL CHANGE
I I
350 - 749 cc-
90 89 88
79 78 77 76 75 74 73 72 71 dBA
REGULATORY LEVEL (SAE J331a, CHP)
FIGURE 7-1 MANUFACTURING UNIT COST INCREASE VS. REGULATORY LEVEL (MANUFACTURER SUPPLIED DATA)
-------
(c) Since there are a wide variety of techniques which can be utilized
in reducing the sound level from a given subsource, manufacturers projected
differing techniques to be used, with attendant differences in costs.
(d) Major model changes were deemed necessary at different study levels.
Data points denoted by an asterisk indicate the study level for which major
model changes were assumed.
Costs associated with the reduction of exhaust system sound levels
are shown in Figure 7-2. Again the large scatter in data indicates that
for some exhaust systems, large reductions in sound levels are relatively
inexpensive while others are considerably more expensive for the same
degree of noise reduction. For example, for one model in the 350 to 749cc
category, a reduction in exhaust sound level from 82 dBA to 70 dBA was
projected by the manufacturer to increase the manufacturing unit cost of
the exhaust system by only $4. For another model in the 750cc and above
category, exhaust noise reduction from 82 to 70 dBA was projected to increase
manufacturing costs by $60. Almost all of the techniques listed for exhaust
systems in Table 7-1 were used to achieve the reduction in this case.
Air intake sound reductions and associated cost increases are shown
in Figure 7-3. There is less scatter in this data, although two of the
models demonstrate wide variance. Most of the other data points fell on a
curve with the following values:
Associated Manufacturing
Air Intake Noise Level Unit Cost Increase
84 —
78 $ 3.0
76 $ 8.0
74 $15.0
72 $30.0
The estimated cost increases of mechanical/drive components versus
degree of noise reduction are shown in Figure 7-4. The scatter here is due
primarily to the use of major model changes and the study levels at which
they were deemed to be necessary.
7.1.2 Manufacturing Unit Cost: Generalized Estimate
The manufacturer-supplied data in the previous section referred to
individual models and techniques. These data were consolidated to obtain
a generally applicable set of techniques at each study level and to assign
a generally applicable cost estimate to each study level, for each class
of motorcycle. In addition, EPA's motorcycle technology contractor
independently estimated the cost of individual techniques for comparison
with the manufacturer-supplied data.
7-4
-------
I/I
r>
I/I
ES
-<•
-:
g
E
'
2-STROKE
4-STROKE
85 84 83 82 81 80 79 78 77 76 74 73 69 68 67 dBA
EXHAUST SYSTEM SOUND LEVEL
FIGURE 7-2 EXHAUST SYSTEM MANUFACTURING UNIT COST INCREASES VS.
SOUND LEVEL REDUCTION (MANUFACTURER SUPPLIED DATA)
-------
I/)
2i
OJ
o
o
o
i
i—i
at
I
350-749CC
350-749cc
2-STROKE
4-STROKE
0
85 84 83
82 81 80 79 78 77 76 75 74 73 72
INTAKE SYSTEM SOUND LEVEL
71 70 69 68 67 dBA
FIGURE 7-3 INTAKE SYSTEM MANUFACTURING UNIT COST INCREASE VS.
SOUND LEVEL REDUCTION (MANUFACTURER SUPPLIED DATA)
-------
i
i
i
• 2-STROKE
• 4-STROKE
*DENOTES MAJOR
MODEL CHANGE
79 78 77 76 75 74 73 72
MECHANICAL/DRIVE SOUND LEVEL
71 70
FIGURE 7-4 MECHANICAL/DRIVE MANUFACTURING UNIT COST INCREASE VS.
SOUND LEVEL REDUCTION (MANUFACTURER SUPPLIED DATA)
-------
The independent estimates of manufacturing cost increases
attributable to the meeting of not-to-exceed regulatory levels were
developed by cost estimating personnel familiar with the machining,
casting, welding and other production processes involved. However, the
estimates must be considered gross engineering estimates only because
of the extreme difficulty in predicting the noise reducing effectiveness
of the techniques used in the analysis. As indicated earlier, the latter
problem is encountered by motorcycle manufacturers as well. The inde-
pendent estimates were in general agreement with the manufacturer data
and are used in the generalized estimates.
For exhaust and air intake modifications baseline estimates were
developed for the cost elements of representative systems, and reasonable
cost ranges were developed for each technique and its associated cost
elements. Direct cost estimates were made for appropriate techniques
affecting mechanical/drive components. These techniques were summarized
in Table 7-1. Independent cost estimates for exhaust system, air-intake
system and mechanical/drive system techniques are summarized in Tables 7-2,
7-3 and 7-4 respectively.
Modification of exhaust and air intake systems are primarily a
matter of degree. For example, one of the most fundamental noise attenu-
ation techniques available for reducing exhaust system sound levels is
increasing muffler volume. Increasing the muffler shell size can increase
shell and finish (e.g., paint or chroming) costs from an estimated $1 to
$6 dollars depending on the size of the original muffler and the increase
in volume. Probable practical limits are a 75 to 100 percent volume
increase for large on-road motorcycles, down to a 25 to 50 percent increase
for small off-road motorcycles. Off-road motorcycles in particular have
very distinct size and weight limitations because of their functional
characteristics. Other techniques that can increase the "equivalent"
volume of mufflers are the use of (for example) 4 into 1, and 2 into 1
exhaust systems, which can increase cost from $7 to $14, and adding cross-
pipes between dual exhaust systems, which can add an estimated $10 to $12
to unit costs. These latter techniques are applicable to motorcycles with
multicylinder configurations only.
Modifying the muffler interior can range from adding a few baffles,
which has a minimal cost impact (generally much less than $1), to elaborate
and complex exhaust flow control and absorption techniques that can add
up to $16 dollars to the cost of the muffler. Exhaust flow control tech-
niques include actions such as adding and modifying reactive chambers,
modifying the core, and so forth. Absorption can be effected by adding
exhaust silencers and/or sound absorption linings of various materials,
7-8
-------
TABLE 7-2
EXHAUST SYSTEM NOISE RF.nilCTION TECHNIQUES AND ESTIMATED COSTS
(INDEPENDENT ESTIMATES)
TECHHIQUK
•INCREASE MUFFLER.
VOLUME
•INSTALL CROSS-PIPES
BETWEEN FEADERS
•MODIFY HEADER
INTERCONNECTIONS
(COLLECTIVE MUFFLERS)
k Into 1
U into 2
3 into 1
2 Into 1
•MODIFY INTERIOR,
•ADD soun> ABSORP-
TION LINING
•THICKEN/REINFORCE
SHELL MATERIAL
CONSTRUCT DOUBLE
WALLS
SPECIAL
APPLICABILITY
DUAL EXHAUST
STSTEM ONLY
MULTI-CYLINDER
MOTORCYCLES
ONLY
AFFECTED
COMPONENTS
AND COST
ELEMENTS
•MUFFLER SHELLS i
FINISH (CHROME,
PAINT
•HEADERS
•CROSS PIPES
•HEADER PIPES
•COLLECTOR BOXES
•ASSEMBLY
•CORE PIPES
•BAFFLES
•REACTIVE
CHAMBERS
•LINING MAT'L
•LINING HOLDERS,
SCREENS, ETC.
•MUFFLER SHELL
•REINFORCEMENT
HARDWARE
MANUFAcniRno UNIT cost
INCREASES (DOLLARS)
(jdiltri
lOOce
1-2
N/A
»M
iJi
1-3
100-
I69ce
1-3
•/A
«/A
l-«
1-3
1-8
170-
3>i9ee
l-li
I/A
»/A
1-12
1-*
1-10
350- 750-
7!>9ce ' i Abov*
1-5
10
Id
lli
U
7
1-lk
1-5
1-12
1-6
12
IV
Id
11
7
1-16
1-T
1-ld
COST VARIABILITY
FACTORS
•DEGREE OF VOLUME
INCREASE
•PRODUCT CLASS
•DEGREE or
MODIFICATION
•PRODUCT
CLASSIFICATION
•TYPE OF LINING
MATERIAL
•COMPLEXITY OF
INSTALLATION
•DEGREE OF THICK-
NESS INCREASE
•DEGREE OF VOLUME
INCREASE
COIMEST3
GENERALLY
PRACTICAL
LBCT -
100* INCREASE
•LABOR
INTENSIVE
•LABOR
INTENSIVE
•GENERALLY
MORE COMPLEX
ASSEMBLY
N/A NOT APPLICABLE
-------
TABLE 7-3
AIR INTAKE SYSTEM NOISE REDUCTION TECHNIQUES AND ESTIMATED COSTS
(INDEPENDENT ESTIMATES)
TECHNIQUE
•INCREASE VOLUMK
•MODirr INTAKE
INLET
•MODITY INTERIOR
•ADD SOUND ABSORP-
TION LINING
•INCREASE MATERIAL
THICKNESS
•CONSTRUCT DOUBLE
WALLS
•SHIELD INLET
•REDUCE INLET
AREA
SPECIAL
APPLICABILITY
ATTECTED
COMPONENTS
AND COST
ELEMENTS
•INLET DUCTINO
•AIR CLEANER
BOOT
•INLET DUCTINO
•ASSEMBLY
•BATTLES
•SILENCERS
•AIR CLEARER
BOOT
•AIR CLEANER
BOOT
•INLET OPEBINO
•INLET OPENINO
MARUPACTURIIIO UNIT COST
INCREASES (DOLLARS)
BCLOV
lOOee
1-2
1-3
1-5
-
-
-
-
-
100-
I69cc
1-2
1-3
1-5
1
1-3
-
-
-
170-
3k9cc
1-2
1-6
1-6
1-2
1-k
-
-
-
350-
7k9cc
1-3
1-6
l-«
1-2
1-6
-
-
-
TSOco
t ABOVE
1-3
1-T
1-10
1-3
1-7
-
-
COST VARIABILITY
FACTORS
•DEGREE OP VOLUME
INCREASE
•PRODUCT CLASS
•DEGREE op
MODIFICATION
•PRODUCT CLASS
NOT USED n COST
ANALYSIS
••0 COST IMPACT
•HO COST IMPACT
COMMENTS
--J
I
-------
TABLE 7-4 MECHANICAL
NOISE REDUCTION TROiMIQUES AND APPROXIMATE COSTS
(INDEPENDENT ESTIMATES)
TECHHIQUE
STIFFEN ma urn CASE WEBS
CHANGE HI! SHAPES
ISOLAEE/REIHFOHCE
COMPONENTS
THICKER/REIRFORCB CASK
COVERS
INCREASE LUBRICATION
M3DIFY PISTOR/CYURDER
REDUCE TOLERARCES/IKPHOVB
FINISH
MODIFY BEARINGS
MODinf ENGINE TIMING AND
DRIVE BELTS/CHAINS
REDUCE VALVE CLATTER
INCREASE FLYWHEEL MASS
MODIFY CRANKSHAFT/CAMSHAFT
MODIFY CLUTCH
MODIFY GEAR/TRANSMISSION
TIGHTEN DRIVE- CHAIR
ENCLOSE DFIVE CHAIN
MODIFY FRAME
APPLICATION
RUBBER OR METAL DWELL BETWEER
FIRS
MODIFY DESIGN
ADD GASKETS. BUSHINGS, ETC.
MODIFY EXCISE, GEAR. CRARKCASE
COVERS
INCREASE PRESSURE LUBRICATION
MODIFY PISTON/CYLINDER DESIGR
AND CLEARANCE
REDUCE TOLERANCES, IMPROVE
FINISH OF MACHINED PARTS
MODIFY BEARING AREA, MATERIAL
CONVERT FROM CHAIN DRIVE TO
HY-VO OR OTHER TYPE
USE HYDRAULIC LIFTERS OH
b-STOKR ENGINES
CRANKSHAFT FLYWHEEL
MODIFY CAMSHAFT DESIGR
USE OF HELICAL GEARS IN-
STEAD OF SPUR GEARS
INSTALL. MODIFY IDLER ARMS
INSTALL STEEL CASE
REDESIGN, INSULATE FRAME
APPROXIMATE MANUFA
INCREASE (DOLLARS)
BELOW
lOOce
1
-
-
-
-
1
-
-
1
-
-
-
-
_
-
100-
I69cc
1
-
2
1-6
1
1
1-2
2
k
-
1
-
-
5
-
6
-
CTURINO UNIT COST
170-
3k9cc
1
-
2
1-10
2
1
1-2
2
5
-
1
-
-
A
-
9
350-
7>«9cc
1
-
2
1-lb
2
1
1-3
2
6
-
1
-
-
9
-
10
2
750cc
1 ABOVE
1
-
2
1-15
2
1
1-3
2
6
-
1
-
-
10
COST
VARIABILITY
FACTORS
•HO. OF COVERS
•DECREE OF'
MODIFICATION
HOT USED IN COST
ANALYSIS*
NOT USED IN COST
ANALYSIS
HOT USED IN
COST ANALYSIS
11
2
COMMENTS
RO COST IMPACT
GENERALLY NO COST
TECHNICAL EFFECT-
IVENESS UNCLEAR
SHOULD RAVE MINI-
MAL COST IMPACT
• BECAUSE OF SPECIAL APPLICABILITY
-------
holders, and configurations with increasing assembly complexity. The unit
cost of sound absorption lining techniques is estimated to range from
less than $1 to $7.
Increasing shell rigidity by using thicker material or different
material can add an estimated $1 to $14 dollars to muffler costs depending
on the extent to which the techniques are used (e.g., how much thicker in
the case of thickening the muffler shell), the size of the original muffler,
and also by how much the muffler volume is increased (if increasing muffler
volume is used as a noise control technique).
Isolation, by mounting the exhaust systems on elastomer pads should
have minimal cost impact.
Exhaust systems of 2-stroke and 4-stroke motorcycles have different
configurations, but the basic sound attenuation techniques and cost impacts
are similar, with some small variations.
An estimate of the impact exhaust system noise control techniques
have on unit costs is provided in Table 7-5, where baseline costs and added
costs are listed for four discrete steps in sound level reduction of a re-
presentative motorcycle in the 750cc and above street legal category. This
was the type of procedure which was used in developing the cost estimates.
In some cases, when estimates were developed for a specific product cate-
gory, estimates for other categories were scaled commensurately.
A similar procedure was used for estimating costs associated with
noise reduction of the air intake and mechanical/drive systems.
In the case of major model changes, the use of liquid cooling was
assumed for street motorcycles. Liquid cooling may not necessarily be
the major change that is used in all cases, but it is felt that its cost
is representative of the magnitude of costs major model changes will incur.
A rough order of magnitude cost estimate for the addition of liquid cooling
to a street motorcycle in the 750cc and above category is provided below.
7-12
-------
TABLE 7-5
COSTS OF EXHAUST SYSTEM HOISE
CONTROL TECHNIQUES (SAMPLE)
CASE
SOUHD LEVEL
COST ELEMENT
SHELL
INTERIOR
MUFFLER LINING
FINISH
(Chrome,
Paint )
ASSEMBLY
OTHER
TOTAL
MODIFIED
MUFFLER
COST
BASELINE
75 dBA
COST
$U.5
$5.0
$1.0
$U.5
$3.0
$18.0
MODIFIED
70 dBA
'ADDED
MODIFICATION (COST
I
• Volume Increased !
10055
• Thickness Increased
100J5
• Interior Modified
• Sound Absorption
Lining Increased
• Volume Increased
• Interior Modified
$3.0
$7.0
$5.0
$3.0
$3.0
$3.0
$2U.O
$1*2.0
1 COMMENT
Approx. 25055
Increase In
Material Cost
Larger and
More Complex
Core
Different
Material} More
Complex Lining
Scheme
Finish Surface
Area Increased
By Volume
Increase
More Complex
Assembly
7-13
-------
LIQUID COOLING: Street Motorcycle, 750cc and Above
(rough order cost approximation)
ITEM COST
Sheet Metal Material $10
Radiator 10
Plumbing 2
Pump 7
Miscellaneous Hardware 4
Fabrication Labor* 47
Total $80
*Includes welding, machining, and assembly.
Summary of Manufacturing Unit Cost Increases (Independent Estimate)
The independent estimate of manufacturing unit cost increases
attributable to meeting not-to-exceed regulatory levels for specific
product categories are summarized in Table 7-6. Table 7-7 offers a
comparison between manufacturer-supplied cost increase data with the
independent estimates, for street motorcycles.
These estimates were derived by using the methodology described
in the previous section. The analysis utilized the assumptions shown in
Table 6-2 for the technology required at each study level.
The data contained in Table 7-6 is shown in Figures 7-5 and 7-6.
Two cases are shown for each product category: (1) cost curves assuming
that relatively straight forward noise reduction techniques can be used
to meet regulatory levels; and (2) cost curves assuming that major model
changes are necessary to meet 80 dBA and lower regulatory levels. In the
case of major model changes, the use of liquid cooling was assumed for
street motorcycles. Conversion to 4-stroke engines was assumed for pure
off-road motorcycles, at the same cost (up to $80 depending on engine
size).
In the independent cost estimate very small differences were
predicted in cost impacts between motorcycles with 2-stroke and 4-stroke
engines, with the exception of those cases requiring 2-stroke to 4-stroke
conversion. As a result, except for the conversion costs (off-road models),
2-stroke and 4-stroke cost impacts are considered equivalent in the in-
dependent cost analysis. Note also that no major model changes were
forecast for motorcycles under lOOcc in size, for the following reasons:
(1) none of the manufacturers indicated that models in this category would
require major redesign to meet specified regulatory levels; and (2) the
existing sound levels of motorcycles in this category are relatively low.
7-14
-------
TABLE 7-6
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE
PRODUCT CLASSIFICATION
STRAIGHT FORWARD DEVELOPMENT
Street-Legal
99cc and Belov
100-l69cc
170-3l*9cc
350-7U9oc
750cc and Above
Off-Road
99cc and Belov
100-l69cc
170-3l*9cc
350-7U9CC
4AJOR MODEL CHANGES
Street-Legal
MANUFACTURING UNIT COST INCREASE
REGULATORY LEVEL (J331a)
86 dBA
i
I
0
0
0
0
0
83 dBA
i
0
2
k
8
10
80 dBA 78 dBA
V
1
75 dBA
I i
0 i 7 17
8 I 25
i
16
22
61
38 92
55 129
30 63
1
i i
0
0
u
k
"^••^""•"^^ t
100-l69cc
170_3U9cc
350-7l*9cc
750cc and Above
Off -Road
100-l69cc
170-3l»9cc
350-71*900
0
2
0 7
8
25
8 20 k2
12
26
i
59
I
i j
j U7 ! 61 ; 87
55 7k ! 118
: i
85 i 108
103
kl
59
89
135
61
78
112
nk
198
7-15
-------
TABLE 7-7
COMPARISON OF MANUFACTURER SUPPLIED COST DATA
WITH INDEPENDENT NOMINAL CASE ESTIMATES
DISPLACEMENT
CATEGORY
;Street Motorcycles;
100-169cc
170-349cc
350-749cc
750 and Above
MANUFACTURING UNIT COST INCREASE
REGULATORY LEVEL (J331a)
83 dBA
MFR.
$ 5.0
.6
2.4
3.1
14.0
6.5
7.3
8.7
13.5
15.5
15.0
IND.
$ 5.0
13.0
17.0
19.0
80 dBA
MFR.
$ 9.0
8.0
14.0
16.6
6.5
21.5
26.3
33.5
36.0
39.0
54.0
35.0
122.0*
IND.
$15.0
43.0
50.0
30.0
103.0*
78 dBA
MFR.
$ 7.3
3.5
54.5
66.0
22.5
57.0
66.5
77.5*
83.5*
115.5*
168.4*
192.0*
66.5
IND.
25.0
38.0
59.0
108.0*
63.0
135.0*
75 dBA
MFR.
$
286.0*
HMD.
87.0*
118.0*
174.0*
198.0*
* Denotes major model change necessary
-------
i
.
•
i
w 24°
g
^ oor*
-I 2ZO
n4
O 0_~
MANUFACTURING UNIT COST INCREASE ( E
h- *- H- H- H- r
,S) 4k 0^ 00 0 CO
o ooooooooc
\} £
+ Is
TRA
AJO
CHI
R M<
-FO
DDEJ
*-
*WA
CH
~~Z
RD 1
^NG
— H
— •**
1OUJ
t
^ez
>-==-
LC
g=^-
-1AN
4
<
4
^
-X
J
JE
X
^x
^
^
J
J
J
'x
_^
/
r'
y
y
/
^^
^
^
^-
/X
7
/
/
p£
^s
/^
I
'
/
/
2
^
/•
X*
— -— •*
|750<
^*35
^50
>350
> *
17(
> 17
>
"100
100
^BEI
c AI
0 - 7
cc A
- 7'
-3.
) - 3
- 16
- 16
,OW
D A
49cc
^D A
9cc
9cc
I9cc
9cc
Ice
100<
BOV
BOV
c
E
!9 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73
SAE J331a REGULATORY NOISE LEVEL (dBA)
FIGURE?- q MANUFACTURING UNIT COST INCREASE VS. REGULATORY NOISE LEVEL
(BASELINE INDEPENDENT ESTIMATE) FOR STREET LEGAL MOTORCYCLES
-------
240
STRAIGHT-FORWARD MODEL CHANGE
MAJOR MODEL CHANGE
350 - 749cc
170-349cc
100- 169cc
350 - 749cc
^1>100- 169cc
>BE LOW lOOcc
-
89 88 87 86 85 84 83 82 81 80 79
SAE J331a REGULATORY NOISE LEVEL (dBA)
FIGURE 7-6 MANUFACTURING UNIT COST INCREASE VS. REGULATORY NOISE LEVEL
(BASELINE INDEPENDENT ESTIMATE) FOR OFF-ROAD MOTORCYCLES
-------
A breakdown by subsource of baseline independent cost estimates
is contained in Table 7-8.
Nominal (Expected) and Worst Case Manufacturing Unit Costs
The preceding cost analysis indicates that there is a significant
difference in total unit cost inpacts for cases involving relatively
"straight-forward" model changes, as opposed to cases involving major
model changes. There is a high degree of uncertainty as to which models
and for which manufacturers major changes will be needed in order to
comply with noise standards, and at which regulatory levels these types
of changes will be necessary. Therefore this analysis is structured for
two cases: (1) the nominal (expected) case; and (2) the worst case.
Assumptions were made, based on data from manufacturers, current motorcycle
sound levels and sound source data provided by manufacturers, as to what
fraction of motorcycle production would require major model changes at
each study level. The assumptions made for the nominal (expected) and
worst cases are listed below.
ESTIMATED NUMBER OF STREET MOTORCYCLES REQUIRING MAJOR MODEL CHANGES
AS THE RESULT OF SOUND CONTROL REGULATORY ACTIONS
REGULATORY LEVEL
(SAE J331a not-to-exceed)
FRACTION OF MOTORCYCLE PRODUCTION
REQUIRING MAJOR MODEL CHANGES
NOMINAL (EXPECTED) CASE
WORST CASE
86 dBA
83 dBA
80 dBA
78 dBA
75 dBA
0%
0%
10%
50%
90%
0%
0%
50%
100%
100%
7-19
-------
For street motorcycles, these assumptions apply to all size cate-
gories above lOOc.c. (no major model changes are expected below lOOc.c.).
For off-road motorcycles, however, different assumptions apply for each size
category. This is due to the unavailability of liquid cooling for off-road
motorcycles and the requirement that off-road motorcycles be single cylinder.
Larger off-road motorcycles are expected to require major model changes (4-
stroke conversion) at higher levels than smaller off-road motorcycles. The
above assumptions for off-road motorcycles are distributed according to the
table below (worst case estimate in parentheses):
Displacement Class (c.c.)
350 and above
170-349
100-169
99 and below
Overall (sales weighted)
Regulatory Level (dB(A)-J331a)
80
100% (100%)
50% (100%)
0% (100%)
0% (0%)
10% (50%)
78
100% (100%)
100% (100%)
100% (100%)
0% (100%)
50% (100%)
Using these assumptions for major model changes, the nominal and
worst case estimates for manufacturing unit cost increases are claculated
and presented in Table 7-9.
7-19a
-------
TABLE 7-8
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE
Page 1 of
DATA
POINT
MODE
SIZE
CATEG.
750 and
Above
350-71*9
170-3»»9
100-169
99 and
Below
DKiuiuru
FUNCTION
Street-
Legal
Street-
Legal
Street-
Legal
Street-
Legal
Street-
Legal
UH
ENG.
TYP.
MSMT
PROC.
J331a '
i
i
J331a
J331a
J331a
J331a
RFPIIf AT^'^Y T ™fll'1T °* ' t\n A \
FROM
0
86
86
86
86
80
EX
N
Y|/D
i
TO
0
83
80
78
75
83
80
78
75
83
80
78
75
83
80
78
75
78
75
EX
75
72
70
67
75
72
70
67
75
72
70
67
75
72
70
67
71
67
IN
75
72
70
67
75
72
70
67
75
72
70
67
75
72
70
67
71
67
M/D
75
73
71
68
75
73
71
68
75
73
71
68
75
73
71
68
69
69
MANUFAr^'iiRTNr. rr>RT THCREASE
OVEH-"
ALL
(0)
10
30
63
ll«6
8
22
55
129
it
16
38
92
2
8
25
61
7
17
EX-
HAUST
EX)
6
13
52
It
9
18
It »t
2
5
13
27
1
3
11
20
3
9
AIR
NTAKE
(IN)
1*
10
16
30
It
6
12
25
2
5
9
20
1
8
Ik
li
8
MECH/
DRIVE
(M/D)
0
7
23
6lt
0
7
25
60
0
16
1*5
1
6
27
0
0
CLASS .
SFMC
SFMC
SFMC
[
SFMC
SFMC
tv)
O
« Regulatory not to exceed noise level applicable to overall (0) level. Subsources are design level.
»* SFMC - Straight Forward Model Change.
MMC - Major Model Change.
-------
TABLE 7-8 (CONT'D)
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE
Page 2 of
UA1A
POINT
MODEL DESCRIPTION
ST7,E
CATEG.
FUNCTION
(cc)
350-71*9
Off-Road
170-3*49
100-169
99cc &
Below
ENG. .MSMT
TYP. PROC.
Off-Road i
j
Off -Road
Off-Road
J331a
1
J331a
REGULATORY LEVELS* ( DBA )
FROM |
0 EX
89
89
t
i
J331a
86
1
80
rIN
M/D j. 0
86
83
<8o
78
86
TO
EX
82
75
72
70
82
83 75
80
78
83
80
72
70
75
72
78 J70
78
75
71
67
IN M/D
82 75
75
72
70
82
75
72
70
75
72
70
71
67
75
73
71
75
75
73
71
75
73
71
69
69
MANUFACTURING COST INCREASE:
OVER- ] EX-
ALL JHAUST
(0)
AIR
INTAKE
(EX) (IN)
1* 2
12
26
59
1|
8
20
1*2
2
8
25
7
17
6
11
20
2
It
7
15
1
™ f CHANGE"*
(M/D) : CLASS.
',
2 : 0 SFMC
6 0
8 7
I1* 1 25
2
U
7
11
1
3 k
11
3
8
14
9 8
0 : SFMC
0 i
6
16
0 SFMC
1
6
0 SFMC
0
* Regulatory not to exceed noise level applicable to overall (o) level. Subsources are design level.
«* SFMC - Straight Forward Model Change.
MMC - Major Model Change.
-------
TABLE 7-8 (CONT'D)
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE
Page 3 of 1*
DATA
POINT
EODEL DESCRIPTION
SIZE
CATEG.
(cc)
FUNCTION
750 and | Street-
Above Legal
350-7U9
170-3^9
100-169
Street-
Legal
Street-
Legal
Street-
Legal
ENG.
TYP.
MSMT
PROC.
J331a '•
J331a
J331a
REGULATORY
FROM
0 ,EX
86
•
.
86
86
86
IN
M/D ]
LEVELS* (DBA)
TO
0
83
80
78
75
83
80
78
75
83
80
78
75.
83
80
78
75
EX
75
72
70
67
75
72
70
67
75
72
70
67
75
72
70
67
IN
75
72
70
67
75
72
70
67
75
72
70
67
75
72
70
67
M/D
75
73
71
68
75
73
71
68
75
73
71
68
7*
73
71
68
MANUFACTURING COST
OVER-
ALL
(0)
10
103
135
198
8
85
108
171*
i»
55
7U
118
2
U7
61
87
EX-
IAUST :
KX)
6
13
2U
52
1*
9
18
1*1*
2
5
13
27
1
3
11
20
AIR
NTAKE
(IN)
U
10
16
30
If
6
12
25
2
5
9
20
1
U
8
lU
NCREASE
MECH?
DRIVE
(M/D)
0
80
95
116
0
70
78
105
0
>»5
52
71
0
1»0
1*2
53
CHANGE**
CLASS .
MMC
g
80
dBA
MML.
%
80
dBA
MMC
« >
80 1
dBA !
i
MMC j
e i
80 !
dBA i
tx)
N)
•Regulatory not to exceed noise level applicable to overall (0) level. Subsources are design level.
•» SFMC - Straight Forward Model Change.
MMC - Major Model Change.
-------
TABLE 7-8 (CONT'D)
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE
Page 1| of
DATA
POINT
MODEL DESCRIPTION
SIZE
CATEG.
(cc)
350-71*9
170-31*9
|
100-169
FUNCTION
Off-Road
ENG.
TYP.
Off-Road
Off-Road
MSMT
PROC.
J331a
J
J331a
J331a
REGULATORY LEVELS* (DBA)
FROM
0 _|
89
89
86
EX
IN
M/D
TO
0
86
83
80
78
86
83
80
78
83
80
78
EX
82
75
72
70
82
75
72
70
75
72
70
IN _
82
75
72
M/D
75
75
73
70 171
82
75
72
70
75
72
70
75
75
73
71
75
73
71
MANUFACTURING COST INCREASE
OVER-
ALL
(0)
u
12
89
112
U
6
59
78
2
1*7
61
EX-
HAUST
(EX)
2
6
11
20
2
li
7
15
1
3
11
AIR
INTAKE
(IN)
2
6
8
ll»
2
U
7
11
1
1*
8
MECH/
DRIVE
(M/D)
0
0
70
78
0
0
1*5
52
0
1*0
1*2
CHANGE**
CLASS .
MMC
a
80
dBA
MMC
60
dBA
MMC
$
so
dBA
^J
K)
"Regulatory not to exceed noise level applicable to overall (0) level. Subsources are design level.
** SFMC - Straight Forward Model Change.
MMC - Major Model Change.
-------
TABLE 7-9
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS
NOMINAL AND WORST CASES
PRODUCT CLASSIFICATION
NOMINAL (EXPECTED) CASE
Street-Legal
99cc and Below
100-l69cc
170-3l*9cc
350-7U9cc
750cc and Above
Off-Road
99cc and Below
100-l69cc
170-3l*9ce
350-7^9cc
WORST CASE
Street-Legal
99ce and Below
100-l69cc
170-3l»9cc
350-7'*9cc
750cc and Above
Off -Road
99ec and Below
100-l69cc
170-3fc9cc
350-7>»9cc
1
MANUFACTURING UNIT COST INCREASE
REGULATORY LEVEL (J331a)
86 dBA
0
0
0
0
0
0
0
U
k
0
0
0
0
0
0
0
u
u
83 dBA
0
2
U
8
10
0
2
8
12
0
2
h
8
10
0
2
8
12
80 dBA
0
10
18
25
37
0
8
40
89
0
28
36
5U
67
0
47
59
89
78 dBA
7
U3
56
82
99
7
61
78
112
7
61
7l»
108
135
7
61
78
112
75 dBA
17
8U
115
170
193
17
87
118
17U
198
7-24
-------
7.1.3 Research and Development Costs
Research and development costs include the cost of: R&D
personnel, laboratory facilities and diagnostic equipment, prototype
motorcycles, materials and components, and production design and drawings.
The impact of research and development cost on unit cost is particularly
difficult to determine because of variances in the sizes and character-
istics of the companies involved, the differences in depth and breadth
of each company's product line, extent of expenditures in the effort that
can be considered "sunk" costs and have already been amortized, unknown
technical complexities and model peculiarities that will be encountered
in the R&D and production design program, differences in available
resources and personnel, differences in cost accounting policies, and
program variables such as the degree of noise reduction required for each
class of motorcycle.
Nevertheless, estimates for amortized R&D cost increases on a
unit basis were provided by three manufacturers. Data from two of the
ccnpanies is relatively consistent and is summarized in Table 7-10. Both
are Category I Manufacturers (manufacturers that produce 100,000 units
or more annually). Data from the other manufacturer (a manufacturer that
produces less than 100,000 units per year) were considerably higher than
the other manufacturers. This is to be expected because total R&D expenses
were allocated over fewer units when estimating costs on a per unit basis.
Based on the available information, a reasonable estimate would be that
the R&D costs on a unit basis for a Category II manufacturer would be
approximately double the unit R&D costs of a Category I manufacturer.
Data for the Category I manufacturers is shown graphically in
Figure 7-7. Data from these manufacturers indicate that R&D costs on a
unit basis tend to vary with development categorization. R&D costs are
significantly higher in those cases where major model changes are indi-
cated, as would be expected. The "best-fit" line for the data points
exhibited are indicated by diamond symbols (^), and identified as
generalized cost estimates in the figure.
The slope of the line for the generalized cost estimate associated
with major model changes is assumed to be the same as that for straight-
forward changes. The generalized cost estimates for Category I
manufacturers are summarized in Table 7-11.
The generalized estimates in Table 7-11 for Category I
manufacturers were modified by two factors to derive the composite
(weighted) average R&D unit cost increases for all manufacturers, shown
in Table 7-12. The two factors considered in deriving the weighted com-
posite are: (1) approximately 86% of all motorcycles sold in the U.S.
are manufactured by Category I manufacturers, and (2) R&D unit costs for
7-25
-------
TABLE 7-10
AMORTIZED R&D COSTS ON A UNIT BASIS -
MANUFACTURER SUPPLIED DATA
r
MANUFACTURER
CATEGORY*
i
I
MANUFACTURER
A
B
DEVELOPMENT
CLASSIFICATION
Straight-Forward
Development
Major Model
Configuration
Change at 78 dEA
Straight-Forward
Development
REGULATORY LEVEL, R&D UNIT |
J331a (dBA) COST |
;
83 3
80 i 10
78 16
75 21
83 ' 3
80 10
78 ' 28 - 35 !
!
'
83 l-1*
80 5.9
78 12.8
i
Major Model ! 83 i 2.0
Configuration Change ! 80 '12.2
at 78 dBA ! 78 ! 38.0
1 •
Category I - Manufacturers that produce 100,000 units or more annually.
7-26
-------
0
Q
<^
W
(Q
w
«
u
2
I-H
H
S
U
H
M
Z
45
40--
35--
30--
25 ••
20 ••
15"
ID-
* MAJOR MODEL CHANGE
0 MANUFACTURER A
• MANUFACTURER B
^GENERALIZED ESTIMATE
MAJOR MODEL CHANGE
STRAIGHT-FOR WARD MODEL CHANGE
82 81 80 79 78
77
76
87 86 85 84 83
REGULATORY NOISE LEVEL (SAE J331a) , dBA
FIGURE 7-7 CATEGORY I . MANUFACTURER'S AMORTIZED R&D COST
ON A UNIT BASIS VS. REGULATORY NOISE LEVEL
7-27
-------
TABLE 7-11
MOTORCYCLE UNIT COST INCREASE DUE TO AMORTIZED R&D EXPENSES:
GENERALIZED COST ESTIMATE FOR MANUFACTURERS
PRODUCING 100,000 OR MORE MOTORCYCLES PER YEAR
CHANGE CATEGORY
• Straight Forward
Model Development
• Major Model Con-
figuration
Change @ 80 dBA
(J331a)
MOTORCYCLE "UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
36 dBA
$1
83 dBA
$2
80 dBA
$8
$32
78 dBA
$1U
$35
75 dBA
$21
$1*2
Note: Derived from data - Category I manufacturers shown in Table 7-10
TABLE 7-12
MOTORCYCLE UNIT COST INCREASE DUE TO AMORTIZED R&D EXPENSES:
COMPOSITE WEIGHTED AVERAGE FOR ALL MANUFACTURERS
CHANGE CATEGORY
• Straight Forward
Model Development
• Major Model
Configuration
Change
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
86 dBA
1
83 dBA
2
30 dBA
9
36
78 dBA
16
uo
75 dBA
2U
U8
Derivation Notes:
1. Available information indicates that manufacturers with production
rates less than 100,000 units per year are likely to have unit R&D'
costs that are twice (2) that of manufacturers with production rates
of 100,000 or more per year.
2. Manufacturers with production rates less than 100,000 units per year,
aell M of all motorcycles sold in the U.S.
7-28
-------
TABLE 7-13
MOTORCYCLE UNIT COST INCREASE DUE TO AMORTIZED R&D EXPENSES:
NOMINAL (EXPECTED) AND WORST CASES
CHANGE CATEGORY
• Nominal (Expected)
Case
• Worst Case
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
86 d£A
$1
$1
83 dBA
$2
$2
80 dBA
$12
$23
78 dBA
$28
$1*0
75 dBA
$1*6
$1*6
7-29
-------
Category II manufacturers are estimated to be double those of Category I
manufacturers. Therefore the composite weighted average for all motorcycle
manufacturers should be roughly 1.14 times the cost of Category I manu-
facturers.
Table 7-13 shows nominal and worst case R&D unit costs associated
with different regulatory levels. These values are used in computing
total unit cost increases.
7.1.4 Tooling and Other Manufacturing Equipment Costs
The use of sound reduction techniques will impact
manufacturing equipment and tooling requirements; most of the impacts
are expected to fall into the tooling category. Tooling and equipment
cost impacts estimated by different manufacturers for various regulatory
levels and modification techniques are summarized in Table 7-14. The
estimates of amortized tooling cost on a unit basis show considerable
variance, as shewn in Figure 7-8. Probable reasons for the wide variance
include differences in: (1) regulatory levels requiring major model
changes, (2) production bases (number of units over which tooling costs
are allocated), and (3) models and production techniques.
Tooling costs on a unit basis tend to be considerably higher for
Category II manufacturers (producing 100,000 units per year cr less),
again because fixed expenses are allocated over fewer units. Generalized
cost estimates for Category I manufacturers are indicated by lines in
Figure 7-8, and summarized in Table 7-15. Estimates for both straight-
forward and major model changes are provided. The generalized estimates
represent an evaluation of trends indicated in manufacturer-supplied data.
The slope for both lines is assumed to be the same. A conservative (high)
estimate of unit tooling costs for major model changes was used.
As in the case of R&D expenses, it would appear that unit tooling
costs for Category II manufacturers are approximately double that of
Category I manufacturers. A composite weighted average for all manufac-
turers was computed using the 1.14 factor derived in the previous section.
The weighted average is summarized in Table 7-16. Composite cost estimates
for nominal and worst cases are summarized in Table 7-17.
7-30
-------
TABLE 7-14
TOOLING AND PRODUCTION EQUIPMENT COST ESTIMATES
MANUFACTURER SUPPLIED DATA
MANUFAC-
TURER
CATEGORY
I
I
I
I
DATA
POINT
1
2
3
4
REGULATORY
LEVEL
78 dBA
75 dBA
83 dBA
80 dBA
78 dBA
TOOLING
COST
$ 70K
$140K
$2.0M
AMORTIZED
TOOLING COST
ON A UNIT
BASIS
$23
$11
$3.5(E)1
$7.0(E)
33. 02
MODIFICATIONS
Major Model Change
Major Model Change
Straight-Forward
Modifications
Major Model Change
Estimated as follows: $70,000 in tooling amortized over 20,000 units for
each of the specified regulatory levels. The $70,000 estimate provided by
the manufacturer.
"Independent estimate.
7-31
-------
tn
oc
90
80
70
60
O
Q
H-
8
0
t
z
D
50
40
30
20
10
0
c
) —
— —
X
—*
r
.-<
MAN!
OST
M
O M/
GENI
AST
^S M
<^M/
•DEN
k--
i
y
• \
\.
/
JFACTURER
RAtGHT-FOR
ODEL CHAN
UOR MODEL
ERALi:
^AIGH
OOEL
UOR X
OTES
SUPPLIED D,
WARD
GE
CHAN
GE
ZED COST EST1MAT
T-FORWARDl
rWANRE I
10DEL
CHAN
MAJOR MOD
I
--<
—•—x
GE
= LCH>
> MAJOR M
CHANGE
a»TA
E
WGE
ODEL
^ STRAIGHT-
^, FORWARD
CH*
a>NGE
85 84 83 82 81 80 79 78 76 75 74
SAE J331a REGULATORY NOISE LEVEL (dBA)
FIGURE 7-8 CATEGORY I MANUFACTURER'S AMORTIZED
TOOLING COST ON A UNIT BASIS VS. REGULATORY
NOISE LEVEL
7-32
-------
TABLE 7-15
MOTORCYCLE UNIT COST INCREASES DUE TO AMORTIZED TOOLING EXPENSES:
GENERALIZED COST ESTIMATE FOR MANUFACTURERS
PRODUCING 100,000 UNITS OR MORE MOTORCYCLES PER YEAR
_„.„._ MOTORCYCLE UNIT COST INCREASE
CATEGORY !
86 dBA
• Straight-Forward $ 0
Model Development
• Major Model Change
g 80 dBA (J331a)
83 dBA
*
REGULAT01
30 dBA
$7
$30
*Y LEVEL (£
78 dBA
$9
$33
SAE J331a)
75 dBA •
$13
$37
TABLE 7-16
MOTORCYCLE UNIT COST INCREASE DUE TO AMORTIZED TOOLING EXPENSES:
COMPOSITE WEIGHTED AVERAGE FOR ALL MANUFACTURERS
CATEGORY
66 dBA I
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
83 dBA ! 80 dBA 78 dBA i 75 dBA
• Straight-Forward
Model Development
• Major Model
Configuration Change
i
$ 0 j $5 ' $8 $10
$3U $38
' $15
' $1*2
7-33
-------
TABLE 7-17
MOTORCYCLE UNIT COST INCREASE DUE TO AMORTIZED TOOLING
EXPENSES: NOMINAL (EXPECTED) AND WORST CASES
1
!
CHANGE CATEGORY
• Nominal (Expected)
Case
• Worst Case
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
86 dBA 83 dBA
$0 j $5
$ o ; $5
!
i
80 dBA
$11
$21
78 dBA
$2U
$38
75 dBA
$39
$U2
7-34
-------
7.1.5 Testing and Certification Costs
For standardized acceleration tests, the basic sound level meter
and accessories required typically cost between $550 and $2,600 (see Table
7-18). A sound level recorder, if necessary, would cost an additional
$2,400. Differences in test types are described for both O.E.M. and
exhaust system manufacturers.
(a) Moving Tests
The test facilities of major vehicle manufacturers are generally
permanent installations, and cost from $225,000 and up. A common alter-
native to setting up permanent facilities is to rent or lease test sites.
A typical facility rental cost would be $10 per motorcycle, or $100 per
day. Based on experience gained in EPA's motorcycle test program, it is
estimated that sound levels can be measured on an average of 20 motor-
cycles per eight-hour period, since the initial set-up time in this case
is miniinal. The tests require three people (two technicians and a rider) ,
and would include six readings in each direction.
For an aftermarket exhaust system manufacturer, considerably more
time would be required to transport motorcycles to rented test facilities,
set-up the test site, and exchange exhaust systems as required. Again,
based on test experience, it is estimated that the sound levels on an
average of eight exhaust system configurations can be measured in an
eight-hour period.
(b) Stationary Tests
Stationary tests are the simplest tests to administer and
require minimal facilities. In addition, the actual test time is almost
negligible. Testing of different exhaust system configurations may re-
quire two persons, but the measurement rate is the same.
The two basic elements for estimating test operation costs are
the measurement rates and the number of personnel required. Costs can
be computed by using an appropriate labor rate combined with the number
of measurements required.
7-35
-------
TABLE 7-18
TYPICAL COST OF SOUND LEVEL METERS AND ACCESSORIES
COMPONENT COST
Type I Sound Level Meter (B&K 2209) $ 1,706
Microphone 3*»3
Piatonphone 1*75
Accessories (tri-pod, vlndscreen, etc.) 100
* 2.62U
Type II Sound Level Meter (B&K 2213) $ 351*
Acoustic Calibrator 177
Accessories 15
$
Sound Level Recorder (B&K 2306) $2,HOO
Source: B&K Catalog (prices as of July 1, 1975)*
7-36
-------
Compliance testing cost estimates from three manufacturers are
summarized in Table 7-19. An EPA estimate appears in Table 7-20. Al-
though EPA estimates of test and administration costs are considerably
lower, manufacturer estimates were used in computing unit cost increases
for testing and compliance requirements. For major manufacturers, unit
costs were figured on the basis of 270,000 unit sales per year, with equip-
ment amortization over a four-year period. A breakdown of the manufacturer
estimated costs is as follows:
Cost Element
o Equipment
o Test and Admin-
istration Costs
Cost
$300,000
$300,000
Cost on
Annual Basis
$ 75,000
$300,000
Subtotal
Unit Cost
Assuming that unit costs for smaller manufacturers are higher, a
reasonable estimate for the composite weighted average for all motorcycles
is $1.5 per unit. In addition, Barley Davidson estimates labeling would
1
add approximately $0.5 to unit costs. Compliance testing and certifi-
cation costs would therefore add approximately $2 to unit costs, and this
value is used in computing total unit cost increases.
7.1.6 Total Unit Cost Increases
Total unit cost increases resulting from compliance with noise
standards are composed of four major cost elements:
(1) Manufacturing unit cost increases.
(2) Amortized R&D costs on a unit basis.
(3) Amortized tooling costs on a unit basis.
(4) Compliance testing and certification costs on a unit basis.
The total unit cost increases versus study levels for the
various motorcycle product categories evaluated in this study are summa-
rized in Table 7-21. The costs are for not-to-exceed regulatory noise
levels as measured by the SAE J331a procedure. "Nominal" and "worst"
T
AMF/Harley-Davidson's reply to Exhaust Emission Notice of Proposed
Rulemak'ing, January 30, 1976.
7-37
-------
TABLE 7-19
ESTIMATED COST OF COMPLIANCE TESTING -
MANUFACTURER SUPPLIED DATA
Manufacturer A
* Additional test equipment and facilities cost:
1. Additional test site for SAE J331a $100,000.
2* Six sets of equipment for performing ISO stationary vehicle
measurements —— $180,000.
* Test Operations and administration costs:
1. Sampling inspections "by SAE J331a of three units /model/
month at 3 units/day —- $16,000 per year.
2. ISO stationary inspection of motorcycles for U.S.
100£ inspection $200,000 per year
1% inspection $ 2,000 per year
Manufacturer B
* Additional Test Equipment and Facilities:
$250,000 - $UOO,000 depending on type of testing.
* Test Operations and Administration Costs:
$100,000 - $300,000 per year depending on required levels of
production verification.
Manufacturer C
* Additional Test Equipment and Facilities Cost: $300,000
* Test Operations and Administration Cost: $300,000 per year.
7-38
-------
^J
to
TABLE 7-20
ESTIMATE OF ANNUAL TESTING AND
CERTIFICATION COSTS—MAJOR MANUFACTURER
Cost Component
Production Verification
(see enforcement section)
Selective Enforcement Audit
(see enforcement section)
Label Verification
(see enforcement section)
25 models
3 persons
3 models
3 persons
25 models
2 persons
1 test each
1 hr/test
15 vehicles/model
1 hr/test
30 tests each
5 min/test
75 hr
135 hr
125 hr
Reporting & Administration
Materials & Miscellaneous
Cost ($)
250 hr
Total 685 hr
@ $20/hr $11,700
5,000
Total $16,700
-------
PROJECTED MOTORCYCLE TOTAL U1IIT COST INCREASES
VERSUS REGULATORY LEVELS
PRODUCT CLASSIFICATION
NOMINAL (EXPECTED) CASE
STREET-LEGAL
99cc and Belov
100 - l69cc
170 - 3!»9cc
350 - 7U9cc
750cc and Above
OFF-ROAD
99 cc and Below
100 - l69cc
170 - 3fc9cc
350 - 7*»9cc
WORST CASE
sl'RKbT-LEGAL
99cc and Belov
100 - l69cc
170 - 3fc9cc
350 - 7**9cc
750ce and Above
OFF-ROAD
99cc and Belov
100 - l69cc
170 - 3fc9ce
350 - 7U9cc
TOTAL UNIT COST INCREASE
REGULATORY LEVEL (J331a)
86 dSA
0
0
0
0
0
0
0
5
5
0
0
0
0
0
0
0
5
5
83 dBA
2
5
13
17
19
2
5
17
21
2
5
13
17
19
2
5
17
21
80 dBA
2
15
U3
50
62
2
15
65
114
2
33
82
100
113
2
52
105
135
78 dBA
16
62
no
136
153
16
80
132
162
16
12U
15U
188
215
16
12U
158
192
75 dBA
U2
125
202
257
280
U2
171
210
266
290
7-40
-------
cases are defined for appropriate categories. For product categories
below lOOcc, no major model changes are forecasted to meet regulatory
levels, so no differences are expected between nominal and worst case
costs in this category. Note that the total unit cost increases speci-
fied here are used to assess unit price impacts.
A breakdown of total unit costs by major cost element is provided
in Tables 7-22 and 7-23. In general, the largest contributor to the unit
cost increase is the manufacturing cost, which typically ranges from be-
tween 60 to 70 percent of the total, followed by amortized R&D and tooling
costs. Certification costs are generally a very small part of total unit
costs. The manufacturing unit cost increases were derived from the gener-
alized cost estimates. These estimates showed relatively good agreement
with cost estimates provided by manufacturers. Amortized R&D, amortized
tooling, and compliance testing and certification costs were derived from
manufacturer-supplied data. Manufacturer-supplied data was cross-checked
for reasonableness of estimates.
7.2 Purchase Price Impacts
The impact of cost increases on purchase price resulting from
noise control measures is a complex action, one which will be determined
in the final analysis by free market interplay between supply and demand.
Some of the alternatives which may be expected to occur as a result of
the interaction of these economic forces as they relate to motorcycle
noise control are presented in this Section.
Table 7-24 provides a rough approximation of the existing price
mark-up structure as motorcycles go from manufacturer to distributor
(if any) to dealer. Distributors for major manufacturers are generally
wholly owned subsidiaries.
One manufacturer indicated that typical price mark-ups range
between 20 to 40 percent at the retail level. Independent references
tend to validate this estimate (see Table 7-24). The worst-case price
increase due to an incremental change in cost is therefore assumed to be
50 percent, assuming that unit cost increases are marked up by typical
rates at each level.
Ultimately, the impact on price could range all the way from
a unit price increase being slightly less than a unit cost increase to
a price increase equal to 1.5 times the cost increase. Individual
representative cases in which four different levels of mark-up could
occur are described below:
7-41
-------
TABLE 7-22
TOTAL UNIT COST INCREASE COMPONENTS:
NOMINAL (EXPECTED) CASE
COST ELEMENT
STREET LEGAL, 750cc &
OVER
• Manufacturing Cost
• R&D2
• Tooling3 (Mfg.
Equipment }
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL, 350-7U9CC
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment }
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL, 170-3U9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg. Eqp. )
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL, 100-l69cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
UNIT COST INCREASE (DOLLARS)
REGULATORY NOISE LEVL'LS-'- (J331a)
86 d£A
83 dBA
10
2
5
2
19
8
2
5
2
17
1»
2
5
2
13
2
1
0
2
5
80 dBA
37
12
11
2
62
25
12
11
2
50
18
12
11
2
1*3
10
2
1
2
15
78 dBA
99
28
2k
2
153
82
28
2k
2
136
56
28
2k
2
110
U3
12
5
2
62
T) dBA
193
U6
39
2
280
170
U6
39
2
257
115
U6
39
2
202
8U
28
11
2
125
REF.
TABLE
1. Not to exceed regulatory levels.
2. Amortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis.
7-42
-------
TAULh 7-22 (CONTD)
TOTAL UNIT COST INCREASE COMPONENTS:
NOMINAL (EXPECTED) CASE
COST KTi?MKNT
STREET LEGAL, 99cc &
BELOW
• Manufacturing Cost
• R&D2
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
OFF-ROAD, 350-7 !»9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
OFF-ROAD, 170-3U9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
OFF-ROAD. 100-169 cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
UNIT COST INCREASE (DOLLARS)
REGULATOR NOISE LEVELS-1- (J331a)
86 dBA
0
0
0
0
U
1
0
0
5
U
1
0
0
5
0
0
0
-
0 _
83 dBA
0
0
0
2
2
12
2
5
2
21
8
2
5
2
17
2
1
0
2
5
80 dBA
0
0
0
2
2
89
12
11
2
114
40
12
11
2
65
8
2
1
2
19
78 dBA
7
2
5
2
16
112
28
2U
2
162
78
28
2k
2
135
61
12
5
2
-
80
75 dUA
17
12
11
2
U2
REF.
TABLE
-•
1. Not to exceed regulatory levels).
2. Amortized R&D costs Jon a unit tjasis.
3. Amortized tooling ccjsts on a unit "basis.
7-43
-------
TAULK 7-22 (CONT'D)
TOTAL UNIT COST IHCRJiASfi COMPONENTS:
NOMINAL (EXPECTED) CASE
COST ELEMENT
OFF-ROAD, 99cc & BELOW
• Manufacturing Cost
• R&D2
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
UNIT COST INCREASE (DOLLARS) REF.
REGULATORY NOISE LEVELS-1- (J331a)
86 dBA
0
0
0
0
0
83 dBA
0
0
0
2
2
80 dBA
0
0
0
2
2
78 dBA
7
2
5
2
16
TABLE
1. Not to exceed regulatory levels.
2. Amortized H&D costs on a unit 'basis.
3. Amortized tooling costs on a unit basis.
7-44
-------
TABLE 7-23
TOTAL UNIT COST INCREASE COMPONENTS:
WORST CASE:
COST ELEMENT
STREET LEGAL, 750cc &
OVER
• Manufacturing Cost
• R&D2
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL. 350-7l*9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL. 170-31*9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
STREET LEGAL, 100-l69c=
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
UNIT COST INCREASE (DOLLARS)
REGULATORY NOISE LEVELS-1- (J331a)
86 d£A
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
p^
83 dBA
10
2
5
2
19
8
2
5
2
17
1*
2
5
2
13
2
1
0
2
5
80 dBA
67
23
21
2
113
51*
23
21
2
100
36
23
21
2
82
28
2
21
2
33
78 dBA
135
1*0
38
2
215
108
UO
38
2
188
7U
UO
38
2
151*
61
23
38
2
12U
75 dBA
198
1*8
1*2
2
290
17U
1*8
U2
2
2&&
118
U8
1*2
2
210
87
HO
1*2
2
1J1
REF.
TABLE
1. Not to exceed regulatory levels.
2. Amortized R&D costs on a unit ijasis.
3. Amortized tooling cj)sts on a u^it basis.
7-45
-------
TOTAL
WORST CASE:
TABLE 7-23 (CONT'D)
UNIT COST INCREASE COMPONENTS:
COST ELEMENT
OFF-ROAD, 35000-7^900
• Manufacturing Cost
• R&D2
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
OFF-ROAD, 170-3U9cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
OFF-ROAD. 100-l69cc
• Manufacturing Cost
• R&D
• Tooling (Mfg.
Equipment )
• Compliance Testing
& Certification Cost
TOTAL
UNIT COST INCREASE (DOLLARS)
REGULATORY NOISE LEVELS-1- (J331a)
86 dBA
U
1
0
0
5
U
1
0
0
5
0
0
0
0
0
83 dBA
12
2
5
2
21
8
2
5
2
17
2
1
0
2
5
80 dBA
89
23
21
2
135
59
23
21
2
105
47
2
1
2
52
78 dBA
112
UO
38
2
192
78
UO
38
2
158
61
23
38
2
124
RKF.
TABLE
1. Not to exceed regulatory levels.
2. Amortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis.
7-46
-------
TABLE 7-24
NEW MOTORCYCLE PRICE MARK-UPS
LEVEL
New Motorcycle
Manufacturers
Distributors
Dealers
MFG.
1
EST.
6 to 12%
20%
to
40%
PRICE
REF. SOURCES
ABC
^B ^_. ^_
0-25% 12-15%
2 2
33% 20-25% 33%
MARK-UP PERCENT
CONSENSUS
Mark-up Cum. Mark-up
^» «•
0-25% 0-25%
20-33% 20-66%
Note: 1
Primary Source Used in the Analysis. Other sources were used
for reference only.
2
Significant price discounting can occur at this level.
Sources: A. International Research and Technology Corporation, "The
Impact of Noise Abatement Standards on the Motorcycle
Industry".
B. Manufacturer supplied confidential data.
C. Motorcycle Industry Council, "Manufacturer's Shipment
Reporting System".
7-47
-------
Price Mark-Up
Case Factor Conditions
I 0.9 This would occur if manufacturer absorbed
part of the incremental cost increase,
and distributors and dealers reduced their
nark-up factors to allow for straight pass-
through of cost increase.
II 1.0 This would occur if manufacturers, dis-
tributors and dealers passed increased
cost straight through to consumers.
Ill 1.2 This would occur if manufacturer and
distributor passed cost straight through
to dealer and dealers either used their
standard mark-up or discounted their
prices somewhat.
IV 1.5 This would occur if unit cost increase
is marked-up by standard rates at each
level.
Cases I and II would be considered very optimistic, primarily
because it is counter to normal pricing mark-up policies, even for "incre-
mental" cost increases. Case III is a more likely possibility because it
takes into account both level of demand and profitability. Case IV would
be considered worst case, because this is the mark-up factor that would
impact demand most. If these mark-up factors reduced demand significantly,
discounting and manufacturing rebate actions would likely take place,
thereby reducing effective mark-up factors to those shown in Case III.
The 1.2 factor is therefore a relatively realistic estimate and is used in
the "nominal" case analysis. The 1.5 factor is used in the worst-case
analysis.
Total unit cost increases determined in the cost analysis are used
as the basis of estimating price increases. In the nominal case, total
unit cost increases are factored by the 1.2 price mark-up factor derived
in the previous section to determine price increases. In the worst case,
total unit costs were factored by a 1.5 price mark-up factor. The re-
sults for the two cases and for each product category are summarized in
Table 7-25, and shown in Figures 7-9 through 7-12. These price impacts
are for regulatory levels as defined by the SAE J331a test procedure.
Average 1975 prices for each of the product categories are shown
in Table 7-26. These prices were used as the baseline reference to
compute the relative price increases summarized in Table 7-27.
7-48
-------
TABLE 7-25
PROJECTED MOTORCYCLE PRICE INCREASES
VERSUS J331a REGULATORY LEVELS
Product Category
Nominal (Expected)
Case*
Street-Legal
99cc and Below
100-l69cc
350-71+9cc
750cc and Above'
Off-Road
99cc and Below
100-l69cc
170-3l49cc
350-7l»9cc
Worst Case**
Street-Legal
99cc and Below
100-l69cc
170-3U9cc
350-7»»9cc
750cc and Above
Off-Road
99cc and Below
100-l69cc
170-31»9cc
350-7^900
Unit Price Increase
Regulatory Level (J331a)
86 dBA
0
0
0
0
0
0
0
6
6
0
0
0
0
3
0
0
8
8
83 dBA
2
6
16-
20
23
2
6
20
25
3
8
20
26
29
3
8
26
32
80 dBA
78 dBA
1
2
18
52
60
7k
2
18
78
137
3
50
123
150
170
3
78
157
201
19
132
163
18U
19
96
158
196
2k
186
231
282
323
2k
186
237
288
75 dBA
- 50
150
2U2
308
336
63
257
315
399
^35
**
* 1.2 price mark-up factor.
1.5 price mark-up factor
7-49
-------
'
Q
W
U
H
S
P
400
360
320
280
240
200
160
80
40
7>0cc
ANE
ABC rVE^ >
350
Jl-
170
100
749cc
34S
cc
- I6«cc
92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75
SAE J331a REGULATORY NOISE LEVEL ( dBA )
FIGURE 7-9 PROJECTED RETAIL PRICE INCREASES VS. REGULATORY NOISE LEVELS
FOR STREET LEGAL MOTORCYCLES ( NOMINAL CASE )
-------
I
I
' H
320
280
240
200
160
120
80
40
-A
» -
.. -*
-<^
A—
—
^
— — <
i... .<
/
r
p7
» —
<
/
/
X
.--<
i
^
i
i
:
1
10
BI
50 -
ro -
9 - 1
LOV
749<
H9c
69cc
100
c
cc
2 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75
FIGURE 7-10
SAE J331a REGULATORY NOISE LEVEL ( dBA )
PROJECTED RETAIL PRICE INCREASES VS. REGULATORY NOISE LEVELS FOR
OFF-ROAD MOTORCYCLES ( NOMINAL CASE )
-------
(-n
' I
440
400
5 360
E320
280
W 24°
g
5 20°
160
2
ft 120
H
§ 80
40
o
1
FIGURE 7
m
x=z
//.
\s&
//
y\
^
*
^
z
^
>
75
2
^
Z
/
/
^-^
)cc >
^
//
3
/
^
J^D
Z
"
I7
7
f^
VBO
/
X
x
^^-
y
X
X
^
x^
*" B
j
350
>170
100
/
ELX7
• 74
• 34
- 16<
W 10
9cc
Ice
cc
PCC
2 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75
SAE J331a REGULATORY NOISE LEVEL ( dBA )
11 PROJECTED RETAIL PRICE INCREASES VS. REGULATORY NOISE LEVELS
FOR STREET MOTORCYCLES ( WORST CASE )
-------
I
I
2
Ann
4UU
360
320
280
240
200
160
80
40
i?
9
f
K=
"*^
XX
X
^
^
/,
f S
/
//
/
t
V
5
/
^-<
>
Y
5
J
••
350
170 1
10(
Bl
- 1<
;LOV
- 74
349
9cc
100
ice
:c
cc
2 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75
FIGURE 7-12
SAE J331* REGULATORY NOISE LEVEL ( dBA )
PROJECTED RETAIL PRICE INCREASES VS. REGULATORY NOISE LEVELS FOR
OFF-ROAD MOTORCYCLES ( WORST? CASE )
-------
TABLE 7-26
AVERAGE 1975 RETAIL PRICE FOR EACH PRODUCT CATEGORY
PRODUCT CATEGORY AVERAGE RETAIL PRICE
FUNCTIONAL CATEGORY SIZE CATEGORY (1975 Sales)
Street-legal 750 cc and over $ 2,571
Street-legal 350-749 cc 1,429
Street-legal 170-349 cc 997
Street-legal 100-169 cc 680
Street-legal Under 100 cc 484
Off-road 350-749 cc 1,379
Off-road 170-349 cc 1,128
Off-road 100-169 cc 851
Off-road Under 100 cc 491
Derived from Motorcycle Industry Council's Manufacture Shipment Reporting System
7-54
-------
TABLE 7-27
PROJECTED MOTORCYCLE PRICE IIJCREASES
ON A RELATIVE BASIS
Product Category
NOMINAL CASE
Street-Legal
99cc and Below
100-169 cc
170-3U9cc
350-7U9cc
750cc and Above
Off-Road
99cc and Below
100-l69cc
170-3U9cc
350-7 U9cc
WORST CASE
Street-Legal
99cc and Below
100-l69cc
170-3U9cc
350-7U9cc
750cc and Above
Off-Road
99cc and Below
100-l69cc
170-3U9cc
350-7U9cc
Baseline
'75 Price'
(Dollars)
$ U8U
$ 680
$ 997
$1,U29
$2,571
$ U91
$ 851
$1,128
$1,379
$ U8U
$ 680
$ 997
$1,U29
$2,571
$ U91
$ 351
$1,128
, $1,379
Relative Price Increase (%)
86 dBA ; . 83 dBA; 80 dBA 78 dBA : 75 dEA
i i
t
1
0 O.U O.U ' 3-9. ; 10.3
0 0.9 2.6 . 10.9 22.1
0 1.6 5.2 13.2 2U.2
0 l.U U.2 11. U : 21.6
0 0.9 2.9 \ 7.2 13.1
1 ;
0 O.U O.U 3.9
0 0.7 2.1 11«2
0.5 1.8 6.9 14.0
O.U 1.8 10.0 14.3
0 0.6 0.6 5.0 13.0
0 1.1 7.U 27. U 37.8
0 2.0 12.3 23.1 31.5
0 1.8 10.5 19.7 27.9
0 1.1 6.6 12.6 16.9
0- 0.6 0.6 U.9
0 0.9 9.2 21.9
0.7 2.3 14.0 21.0
0.5 2.3 14.6 20.9
7-55
-------
7.3 Replacement Exhaust System Price Impacts
Using manufacturer-supplied data and an independent estimate, the
purchase price increases expected for 4 into 1 and 2 into 1 exhaust systems
were calculated. These figures, shown in Tables 7-28, 7-29, and 7-30 indi-
cate that replacement exhaust systems would cost nearly as much as original
equipment replacement systems sold by the vehicle manufacturer.
7-56
-------
TABLE 7-28
EXHAUST SYSTEMS
TYPICAL PRICE MARK-UPS
Cost /Price Source
!
i
Muffler Cost ;
•
Header Cost
Total Cost •
Profit Margin j
Net Price to Distributor
Net Price to Dealer
Suggested Retail Price
.— i
Source :
1 . Independent
2. Manufacturer
1
1
2
2
2
U into 1
Exhaust System
Dollars Mark Ut>
2 into 1
Exhaust System
Dollars Mark-Un
$19 j $17
$38 JH^
$57
$ 7
$61;
$90
$1UO
X
2.U5X
$36 X
$ 1» i
$UO i
$60
$90 2.5X
cost estimate.
Supplied Data.
TABLE -7-29
INCREASE IN MUFFLER COSTS VERSUS
REGULATORY LEVELS
Muffler
U into 1* Cost
Percentage Increase
2 into 1*» Cost
Percentage Increase
Baseline
Cost
$18
$17
83 dBA
$2U.O
+33%
$21.0
+2U*
REGULATORY
80 dBA
$31.0
+72*
$26.0
+52*
LEVEL
(J331a)
78 dBA 75 dBA
$1*2.0
+133*
$35.0
+106*
$70.0
+289*
$58.0
+2H1*
* Motorcycle 750cc and above assumed.
*• Motorcycle 350-7U9cc Assumed.
Source: Independent Estimate
7-57
-------
TABLE 7-30
INCREASE IN EXHAUST SYSTEM PRICES
VERSUS REGULATORY LEVELS
Exhaust System
U into 1 Price
Percent Increase
2 into 1 Price
Percent Increase
Baseline
Price 83 dBA
lUo $152
90 $100
+11*
Regulatory Levels
80 dBA 78 dBA 75 dBA
$169
$113
+26*
$196
+UO*
$135
+50*
$265
+89*
$193
+11U*
Source: Independent Estimate.
7-58
-------
7.4 Operation Costs
As discussed in Section 6.3 the principal operation cost associated
with lower levels of sound control is the impact on fuel economy. Based
on the fuel penalties in Section 6.3.2, the "nominal" and "worst" case
estimates for fractional reduction in fuel economy are listed below (all
size categories combined):
Regulatory Level (dB(A), J-331a)
Percent
83 J30 78 J75
Street: Nominal Case 0 2 7.5 14
Worst Case 0 4 12 15
Off-road: Nominal Case 0.5 4 7 —
Worst Case 1 58 —
Several motorcycle review magazines routinely measure fuel economy
of motorcycles tested. Testing sequences are not specified and undoubtedly
vary from test to test and magazine to magazine. However, a review of
recently published data from Cycle and Cycle Guide magazines indicate that
estimates of 45 m.p.g. for street motorcycles over 170c.c. ana 70 m.p.g. for
street motorcycles 170c.c. and under are reasonably consistent with reported
results. These estimates generally agree with manufacturer-supplied infor-
mation. The data in Section 5 indicate that motorcycles under 170c.c. travel
about 2/3 the annual distance of motorcycles over 170c.c. Further, the data
in Section 2 indicate that motorcycles under 170c.c. make up approximately
six percent of the street motorcycle population. These figures can be
combined for a composite fuel economy of current street motorcycles of about
47 m.p.g. Two-stroke engines generally display somewhat lower fuel economy
than 4-strcke models, but large consistent differences were not noted. From
these same reports, 35 m.p.g. for pure off-road motorcycles over 170c.c. and
70 m.p.g. for off-road motorcycles under 170c.c. is assumed. Mileage data
indicate no significant difference in annual mileage between large and small
motorcycles, so these can be combined for a composite 60 m.p.g. figure.
Based on 1500 miles per year for street and combination motorcycles,
530 miles for off-road motorcycles and $0.60/gallon of gasoline, the annual
operation expense attributable to sound reduction is estimated to be
(dollars/year):
7-59
-------
Street: Nominal Case
Worst Case
Off-road:
Nominal Case
Worst Case
Regulatory Level (dB(A)y J-331a)
86 83 80 78 75
0
0
0
0
0.03
0.05
0.40
0.75
0.25
0.30
1.50
2.25
2.7
3.0
0.45 —
0.50 —
7.5
Maintenance Costs
Estimates were made in Section 6.3 on the additional number of
labor hours per year required to maintain motorcycles as a result of sound
reduction. There has been no indication that at lower sound levels exhaust
systems or other parts are any less durable than current systems so no
increase in maintenance parts is expected. The nominal and worst case
increased labor estimates are listed below (all size categories combined;
hours/year):
Regulatory Level (dB(A), J-331a)
86 83 80 78 75
Street: Nominal Case
Worst Case
Off -road: Nominal Case
Worst Case
0
0
0
0
1/16
1/8
1/4 1/2 3/4
3/8 3/4 3/4
1/4
3/8
3/8 —
1/2 —
Although many motorcyclists do their own maintenance, for costing
purposes maintenance at a moderate cost repair facility with a labor rate
of $16/hour is assumed. The resulting increased annual maintenance costs
are listed below (dollars/year) :
i
tegulatory Level (dB(A), J-331a)
Street:
Off -road:
Nominal Case
Worst Case
Nominal Case
Worst Case
86
0
0
83 80 78
0
0
1
2
4
6
4
6
8
12
75
12
12
6 —
8 —
7-60
-------
7.6 Costs of EPA Air Emission Requirements
The assessed costs and impacts of this proposed regulation will be in
addition to those costs and impacts attributable to EPA's motorcycle air
emission regulations (40 FR 1122, January 5, 1977). EPA studies using
information supplied by various manufacturers indicated that the cost of
compliance with the air emission standards for 1978 would result in an
average increase in retail cost of 47 dollars per motorcycle. This cost
would be partially offset by an average discounted lifetime fuel savings
of 33 dollars and an undetermined savings in maintenance and improved
reliability of the product. The average incremental cost increase for the
1980 standards was estimated to be $9, which included a small additional
improvement in fuel economy. The manufacturers estimated that fuel economy
improvements associated with the 1978 emission standards would range as
high as 65 percent with an average increase of 20 percent. No significant
decrease in sales or shift in market shares (between manufacturers) was
expected to result from the implementation of that regulation.
7-61
-------
SECTION 8
ECONOMIC IMPACT ANALYSIS
-------
Section 8
ECONOMIC IMPACT ANALYSIS
8.1 New Motorcycle Sales Forecast
8.1.1 Historical New Motorcycle Sales and Trends
Demand for new motorcycles increased at an average rate of 27
percent each year between 1967 and 1973, but declined 22 percent in
1974 and 25 percent in 1975, according to estimates of new motorcycle
sales shown in Table 8-1. The registration data shown in Table 8-1 and
in Figure 8-2 are relatively precise, but do not represent total sales,
since off-road- and competition models are not required to be registered
in most states. Total motorcycle sales data for the 1973 to 1975 period
was derived from the Motorcycle Industry Council's Manufacturing Shipment
Reporting System, which represents shipment data of the six largest manu-
facturers to their dealers. This is the closest approximation of actual
retail level sales that is available at this time. Based on motorcycle
registrations (Table 2-4), the six largest manufacturers combined have
accounted for approximately 94 percent of the total market over the duration
of the reporting period (1973-1975). This was accounted for in establishing
the data base for analysis by'factoring all data with the 94 percent
factor.
Definitions used in the Manufacturers Shipment Reporting System are
contained in Table 8-2. The reporting system was specially formatted for
this study to provide sales data for the product categories shown in Table
8-3.
Complete monthly sales data from January 1973 through December
1975 for total motorcycle unit sales, retail and wholesale, and regional
sales data has been provided by the Motorcycle Industry Council to the
EPA.
Sales by Product Category
The breakdown of 1975 sales by product category shown in Figure 8-3
indicates that on-road motorcycles accounted for 48 percent of the total,
combination motorcycles 25.5 percent, and off-road 26.5 percent. Street
legal motorcycles therefore made up 73.5 percent of the sales total. Over
one-third of the motorcycles (36.3 percent) are on-road motorcycles 250cc
and above, the majority of the motorcycles in this category having 4-stroke
engines. Almost all of the off-road motorcycles from 100 to 349cc have
2-stroke engines.
8-1
-------
(1)
Table 8-1 NEW MOTORCYCLE UNIT SALES DATA (1967-1975)
NEW MOTORCYCLE NEW MOTORCYCLE CHANGE FROM
Year REGISTRATIONS(l) SOLD (EST) PREVIOUS YEAR
1975
1974
1973
1972
1971
1970
1969
1968
1967
746,778
1,024,084
1,189,789
1,006,143
928,185
751,291
549,933
437,498
287,058
(2)
883,820
(2)
1,180,138
(2)
1,520,741
(2)
1,314,315
(E)
1,238,000
(E)
1,002,000
(E)
733,000
(E)
583,000
(E)
383,000
-25%
-22%
+16%
+ 8%
+24%
+37%
+26%
+52%
-
(1)
Sources: R. L. Polk Registration Data
(2)
Motorcycle Industry Council, "Manufacturer's Shipment
Reporting System" (data representing approximately
94% of estijnated retail level sales was factored to
obtain total estimate).
(E)
New motorcycle registration in these years estimated
to be 75% of new motorcycles sold (based on 1972,
1973 data).
8-2
-------
oo
LL.
O
oo
Q
i
00
3
O
1,500
1,250
1,000
750
500
250
o
«/)
1,250
1,000
750
500
250
SOURCES:
1. 1972-1975 DATA:
• MOTORCYCLE INDUSTRY COUNCIL,
"MANUFACTURER'S SHIPMENT
: REPORTING SYSTEM"
, 2. 1967-1971 DATA:
ESTIMATES DERIVED FROM
REGISTRATION DATA
1967 68 69 70
71 72 73
YEAR
74
75
FIGURE 8-1 NEW MOTORCYCLE SALES, 1967 - 1975
SOURCE
MOTORCYCLE
COL NCIL
1967 1968 1969 1970 1971 1972 1973 1974 1975
YEAR
FIGURE 8-2 U.S. NEW MOTORCYCLE REGISTRATIONS, 1967 - 1975
8-3
-------
TABLE 8-2
MOTORCYCLE INDUSTRY COUNCIL
MANUFACTURER'S SHIPMENT REPORT
DEFINITIONS
MOTORCYCLE
A vehicle which la fully or partially
propelled by a power source other than
muscular power and designed to travel
with not more than three wheels in
contact with the ground.
INCLUDED IM THIS REPORT AREl
Two wheel.motorcycles
Motorcycles with aide cars
Three wheel motorcycles
Mini-cycles
Mini-bikes
cx> All-terrain two and three wheels
I Motorized bicycles
Motor scooters
Mopeds
SPECIFICALLY EXCLUDED FROM THIS REPORT ARE:
Oolf carts
Tractors
Equipment designed specifically
for In factory industrial uses
Three wheel vehicles with a full
passenger enclosure
SHIPMENTS
Net wholesale shipments of. Motorcycles
from manufacturers or distributors to
retail dealers. Returns and adjustments
trots, original shipments should be de-
ducted in the month they occur, not
applied to the original wmth shipped.
PARTICIPATING MANUFACTURER
The motorcycle manufacturers or whole-
sale distributors who submit regular
shipment reports. The initial partici-
pating manufacturers are American Honda,
Yamaha International, U.S. Suzuki,
Kawasaki Motors, Harley-Davidson, and
Norton Triumph. Additional partici-
pation by other manufacturers will be
approved individually by the M.I.C.
Board of Directors,
ENGINE TYPES
Two stroke cycle engine
An engine which requires two strokes
of the piston to complete one combus-
tion sequence composed of intake,
compression, combustion, and exhaust.
The fuel/air mixture la ignited once
for every crankshaft rotation.
Four stroke cycle engine
An engine which requires four strokes
of the piston to complete one combus-
tion sequence composed of intake,
compression, combustion, and exhaust.
The fuel/air mixture is ignited once
for every two crankshaft rotations.
Other
All engines which do not fall into
either of the above categories.
WHOLESALE PRICE
The lowest price at which .the motorcycle model
is normally sold to dealers f.o.b. point of
manufacture or point of entry. This whole-
sale price would not consider such extraordin-
ary items as discounts, special promotional
allowances, rebates or other Incentives.
RETAIL PRICE
The estimated retail value of a motorcycle model
as published on manufacturer "suggested retail
prices". If more than one regional price is
published, this should be the lowest of the
alternative retail prices and should not Include
Items such as transportation charges, set-up
charges, dealer preparation charges, taxes, etc.
MODEL TYPE
On-Yoad motorcycle
A motorcycle which Is certified by its manu-
facturer as being in compliance with the
Federal Motor Vehicle Safety Standards, and
Is designed primarily for use of public roads.
Off-road motorcycle
A motorcycle which is not certified by its manu-
facturer as being in compliance with the Federal
Motor Vehicle Safety Standards.
Combination motorcycle
A motorcycle which is certified by Its manu-
facturer an being in compliance with Federal
Motor Vehicle Safety Standards, designed with
the capability for use on public roads as
well as off-road recreational use.
-------
Table 8-3
MOTORCYCLE INDUSTRY COUNCIL MANUFACTURER'S
SHIPMENT REPORTING SYSTEM CATEGORIES*
Function
On-Road
Combination
Off-Road
Size (Engine Displacement)
Under 50cc
50 - 99cc
100 - 169cc
170 - 349cc
350 - 449cc
450 - 749cc
750 - 899cc
900cc and above
Engine Type
2-stroke
4-stroke
*Special categories devised for purposes of this study, only.
Normal reporting system has different size categories.
The on-road and combination categories correspond to the street-legal
category used in the cost analysis. Size categories were selected to
provide flexibility in the event product categorizations were required
for regulatory purposes, and because it was desirable to evaluate
economic impacts in each category.
8-5
-------
OFF-ROAD (26.5%)
UNDER 100 cc
(13.5%)
UNDER 100 cc (.1%)
100-169 cc (2.6%)
170-349 cc (3.1%)
100-169 cc
(6.0%)
170-349 cc
(4.8%)
AND ABOVE
350 cc (2S)
UNDER 100 cc
(4.8%)
350-749 cc
(23.4%)
100-169 cc
(8.6%)
170-349 cc
(8.7%)
COMBINATION (25.5%)
350-749 cc
(3.2%)
STREET (43%;
OVER 750 cc
(18.9%)
STREET LEGAL (73.5)
] 2 STROKE
J 4 STROKE
FIGURE 8-3 BREAKDOWN OF NEW MOTORCYCLE SALES BY PRODUCT CATEGORY: 1975
8-6
-------
In the actual data base, there were no motorcycles in the following
categories: any motorcycle under 50cc; combination motorcycles - 750cc and
above; and off-road motorcycles 750cc and above. In fact there were very
few off-road or combination motorcycles 450cc and above.
Total On-Road, Combination, and Off-Road Sales
Total motorcycle unit sales, including on-road and combination-
type models of all cc classes, reached a level of 1,522,354 units in 1973,
generating revenues of $1.175 billion dollars for the motorcycle industry.
The succeeding years, however, saw a decline in unit sales to 1,190,046
units in 1974, a drop of 21.8 percent, and to 885,117 units in 1975, a
decrease of 25.6 percent over 1974. While the unit volume of motorcycle
sales declined by almost 42 percent over the three year period, total sales
revenue declined by only 9.1 percent. This is accounted for by the large
increases in the average price of motorcycles during this period, from
an average price of $814 in 1973 to $1,095 in 1974, an increase of 34.6
percent, and to $1,278 in 1975, an increase of 16.7 percent.
Of the three functional forms of motorcycles (on-road, off-road,
and combination), unit sales of on-road motorcycles declined the most
during 1973 to 1974, from a level of 655,241 units to 481,689 units, or
26.5 percent. All three types experienced significant price increases
during 1974, with on-road motorcycles registering the largest increase
(42.2 percent). During 1974, off-road unit sales declined by 22.3 percent,
with combination bike sales falling 15.9 percent. New motorcycle sales
data for total on-road, combination, and off-road motorcycles in units and
retail level dollars derived from the MIC Manufacturer's Shipment Reporting
System are summarized in Table 8-4.
In 1975, the rate of price inflation for motorcycles subsided
significantly as did the rate of decline in unit sales (which decreased
by 51.7 percent). The relative market shares of the three functional types
of motorcycles changed significantly over this period, with the share of
combination motorcycles declining from 36.5 percent to 25.5 percent. In
contrast, on-road and off-road motorcycles increased their shares, from 43
percent to 48 percent, and from 20.2 percent to 26.5 percent respectively
over the 1973 to 1975 period.
8-7
-------
Table 8-4 NEW MOTORCYCLE SALES DATA FOR TOTAL, ON-ROAD, COMBINATION
AND OFF-ROAD CATEGORIES (1972-1975
TOTAL 1972 1973 1974
New Motorcycle Sales 1,314 1,522 1,190
(Thousands of Units)
(1)
Average Retail Price $ 756 $ 814 $1,095
(Dollars)
New Motorcycle Sales $ 994 $1,175 $1,188
(Millions of Dollars)
ON-ROAD
New Motorcycle Sales 546 655 482
(Thousands of Units)
Average Retail Price $1,048 $1,087 $1,546
(Dollars)
New Motorcycle -Sales $ 572 $ 677 $ 684
(Millions of Dollars)
COMBINATION
New Motorcycle Sales 542 556 468
(Thousands of Units)
Average Retail Price $ 598 $ 639 $ 819
(Dollars)
New Motorcycle Sales $ 324 $ 341 $ 346
(Millions of Dollars)
OFF-ROAD
New Motorcycle Sales ' 226 308 239
(Thousands of Units)
Average Retail Price $ 434 $ 545 $ 717
New Motorcycle Sales $ 98 $ 158 $ 158
(Millions of Dollars)
1975
885
$1,278
$1,069
425
$1,805
$ 725
226
$ 834
$ 179
235
$ 758
$ 167
*Discrepancies in 1973-1975 Data due to derivation technique used on
monthly data series.
Source: Motorcycle Industry Council, "Manufacturers Shipment Reporting System"
(Data representing approximately 94 percent of estimated retail level sales in
units and dollars factored to derive data shown in Table).
8-8
-------
TABLE 8-5
MOTORCYCLE MARKET SHARE, BY FUNCTION
On-Road
Off -Road
Combination
1973
43.04
20.2
36.5
1974
40.47
20.08
39.32
1975
48.0
26.5
25.5
On-Road Motorcycle Sales by c.c. Class
While total on-road motorcycle unit sales declined from 655,000
units to 425,339 units over the period 1973 to 1975, there were significant
differences in the rates of decline among the various cc classes over this
period. Sales of motorcycles of over 900c.c. displacement increased,
however, by 240 percent in 1974 and by 65 percent in 1975, from 15,373
units to 86,335 units. Sales of on-road motorcycles in the less than
lOOc.c. category went from 25,267 units in 1975 to only 659 units in 1975.
In general, market shares of on-road motorcycles shifted towards the larger
cc classes.
TABLE 8-6
ON-RQAD MOTORCYCLES MARKET SHARE BY CC CLASS
Less than lOOcc
100 - 169cc
170 - 349cc
350 - 449cc
450 - 749cc
750 - 899cc
Greater than 900cc
1973 %
3.9
8.6
12.16
32.32
24.74
18.19
2.4
1974 %
.8
4.2
9.2
32.29
25.78
16.79
10.88
1975 %
.15
5.3
6.4
25.7
23.68
18.00
20.62
8-9
-------
Combination Motorcycle Sales, by cc Class
All categories of combination motorcycles registered dramatic
declines in unit sales between 1973 and 1975, with corresponding declines
in total dollar revenues. The market for combination motorcycles is domi-
nated by motorcycles in the 100 to 349 cc classes (the 100 to 169 cc and
170 to 349 cc groups). Together they accounted for 69% of unit sales in
1973, for 74% in 1974 and for 69% of sales in 1975. These two classes
suffered declines in unit sales proportionately greater than all of the
other classes.
Table 8-7 COMBINATION MOTORCYCLES MARKET SHARE BY CC CLASS
Less
100
170
450
than 100 cc
- 169cc
- 349cc
- 749cc
1973 %
19.7
36.2
33.2
.5
1974 %
15.59
34.35
39.73
.2
1975 %
18.44
33.86
34.55
.6
Off-Road Motorcycle Sales by cc Class
Historically, total unit sales of off-road motorcycles have declined
from a level of 289,224 units in 1973 to 220,757 units in 1975, a decrease
of 23.7 percent. Revenues, however, increased by 5.8 percent over this
period. This revenue increase is accounted for by the increases in average
unit price of off-road motorcycles, from $545 per motorcycle in 1973 to
$758 in 1975.
Traditionally, the majority of off-road unit sales have been
claimed by the 0 to 99, the 100 to 169, and the 170 to 349 cc classes. In
1973, these three groups accounted for 94.0 percent of sales, in 1974 for
92.4 percent, and in 1975 for 91.8 percent of sales. Over the 1973 to
1975 interval, the distribution of market share by cc class did not change
significantly. (See following table.)
8-10
-------
TABLE 8-8
OFF-ROAD MOTORCYCLES MARKET SHARE BY CC CLASS-PERCENT
Less
100
170
350
450
than lOOcc
- 169cc
- 349cc
- 449cc
- 749cc
1973
63.7
18.4
11.9
4.3
1.7
1974
53.3
27.3
11.8
5.2
2.4
1975
50.4
23.2
18.2
6.6
1.6
8.1.2 Recent Market Developments
Over the period 1973 to 1975 total unit motorcycle sales declined
by 42 percent, while the average unit price of motorcycles increased by 57
percent.
This sales decline occurred at a time when the U.S. economy was
experiencing its worst recession and inflation of the post-war period.
Real GNP (in 1972 dollars) declined in 1974 and again in 1975; real per-
sonal disposable income declined by 1.4 percent in 1974 and increased
slightly in 1975. The unemployment rate moved from 4.9 percent of the
work force in 1973 to 5.6 percent in 1974 and increased to the record high
rate of 8.5 percent in 1975. Additionally, the inflationary situation be-
came severe. As measured by the consumer price index, the rate of inflation
reached 11.1 percent in 1974 and 9.2 percent in 1975.
Given this recessionary environment, the consumer drastically cut
back on expenditures. In 1974, real personal consumption expenditures for
durable commodies declined by 7.0 percent while the decline in 1975 was
2.6 percent. (See following, table.)
8-11
-------
TABLE 8-9
HISTORICAL ECONOMIC INDICATORS
REAL GROSS NATIONAL PRODUCT
% CHANGE
REAL DISPOSABLE INCOME
% CHANGE
UNEMPLOYMENT RATE
% CHANGE
REAL DURABLE CONSUMPTION
% CHANGE
CONSUMER PRICE INDEX
% CHANGE
IMPLICIT PRICE DEFLATOR
% CHANGE
1973
1,233.4
5.3
855.7
6.8
4.9
-13.4
120.9
8.7
1.330
6.2
1.0590
5.9
1974
1,210.7
-1.8
843.7
-1.4
5.6
15.8
112.5
-7.0
1.477
11.1
1.1625
9.8
1975
1,186.1
-2.0
856.7
1.5
8.5
51.0
109.5
-2.6
1.613
9.2
1.2633
8.7
While real personal consumption expenditures on durable comodities
declined from $120.09 billion to $109.5 billion, or by 9.5 percent from
1973 to 1975, unit sales of motorcycles declined by 57 percent. This
dramatic drop in slaes can be attributed to three major factors:
(a) Demographic trends in the motorcycle buying group,
(b) the impact of the recession on the real purchasing power of potential
motorcycle buyers, and
(c) the impact of increased motorcycle prices.
Demographic Developments
Evidence indicates that the relevant consuming group for motorcycles
were males in the age cohort 20 through 34 years. The relevant demographic
group for analysis of buyer behavior is the number of males with income in
this age group.
Over the period 1973 to 1975, the growth rate for the number of
males with income declined. Thus the effective demographic market for
motorcycle sales was impaired over this period. The following table gives
8-12
-------
the percentage changes in the number of males with income in the age
cohorts 20 to 24 and 25 to 34 years. The large age cohort, males 25 to
34 years, suffered declining rates of growth in 1974 and 1975. The age
group 20 to 24 years increased its growth rate in 1974 but shewed vir-
tually no growth in 1975. The long-term growth potential for motorcycle
sales will be constrained by the growth rates in these effective popula-
tion age groups, unless there is a structural shift in the buying patterns
of older age groups.
TABLE 8-10
PERCENT CHANGE IN THE NUMBER OF MALES WITH INCOME
Males,
Males,
20 -
25 -
24
34
1973
2.46
4.6
1974
3.17
3.83
1975
.6
1.36
TABLE 8-11
MOTORCYCLE BUYER'S DEMOGRAPHIC PROFILE
Sex
Male
Female
All Owners
91%
9%
Marital
Status
All Owners
Age
Under 16 years
16 - 17 years
18 - 20 years
21 - 24 years
25 - 29 years
30 - 39 years
40 - 49 years
• w j
50 and over
Undesignated
Total
Median age
13%
10%
13%
15%
15%
19%
10%
4%
1%
100%
24 yrs.
Married
Single
Widowed/Divorced
Undesignated
Total
Education
8th grade or less
High school incomplete
High school graduate
College incomplete
College graduate
Undesignated
Total
49%
48%
2%
1%
100%
10%
24%
33%
20%
11%
2%
100%
Source: Gallup Organization, "Survey of Motorcycle Ownership, Usage, and
Maintenance".
8-13
-------
Real Income Trends
While the real disposable income (in 1972 dollars) for the U.S.
as a whole declined by 1.4 percent in 1974, the real mean income (in 1974
dollars) of the effective market for motorcycles declined by more than
three tiroes that amount, by 4.6 percent. This age group traditionally is
more seriously affected by downturns in the economy than older age groups.
The age group/ males 20 to 34 years, which comprises between 36 and 37
percent of the age group 20 to 34 years, suffered a decline in real mean
income of 6.6 percent. Nor did the real earning power of the age group
20 to 34 years recover in 1975 when the total U.S. real income increased
by 1.5 percent. Instead, the real incomes of potential motorcycle buyers
actually declined by 3.4 perent. (See Table.)
Thus with a declining rate of growth in the number of potential
buyers and an absolute decline in the real incomes of this group, the
market environment for motorcycle sales in 1974 and 1975 was severely
impaired.
TABLE 8-12
PERCENT CHANGES IN REAL INCOME OF MOTORCYCLE BUYERS
Disposable Income for the
U.S. (1972 $)
Mean Income (1974 $) Males,
20 to 34 years
Mean Income (1974 $)
Males, 20 to 24 years
Mean Income (1974 $)
Males, 25 to 34 years
1974
-1.4
-4.6
-6.6
-4.1
1975
+1.5
-3.4
-6.3
-2.8
Price Trends
The average unit price of motorcycles increased from $814 in 1973
to $1,095 in 1974, or by 34.6 percent. During the same period, the price
of all other goods competing for the consumer budget, as measured by the
Consumer Price Index, increased by 11.1 percent. Thus the relative price
of motorcycles vis-a-vis all other commodities increased three-fold in one
year. Nor did this competitive disadvantage of motorcycles correct itself
8-14
-------
in 1975, although the situation was ameliorated somewhat; the average
price of motorcycles increased by 16.7 percent in 1975 as opposed to a
9.2 percent increase in the Consumer Price Index.
Table 8-13 PERCENT CHANGES IN THE AVERAGE UNIT PRICE OF
MOTORCYCLES AND THE CONSUMER PRICE INDEX
Average Unit Price of Motorcycles
Consumer Price Index
1974
+34.6
+11.1
1975
+16.7
+9.2
With a deteriorating effective purchasing power base for
motorcycle sales and a growing uncompetitiveness of motorcycles vis-a-vis
other commodities, the severe decline in unit motorcycle sales over the
period 1973 to 1975 is understandable.
8.1.3 Baseline Forecast of New Motorcycle Sales
The analysis of the market environment for motorcycles and the
price of motorcycles (and other prices) over the period 1973 to 1975
indicated the approach to model statistically the determinants of demand
for unit motorcycle sales. Statistical equations were estimated econo-
metrically by relating unit motorcycle sales {by type and function) to
demographic, income, prices, and motorcycle characteristics (i.e., price)
over the period 1973 to 1975. Given these estimated equations, and the
forecasts of the explanatory variables from Data Resources, forecasts of
unit sales and revenues (given prices) for each class of motorcycle were
generated.
The forecasting model used to predict future sales in the absence
of noise regulations is described in appendix F. Total motorcycle unit
sales are forecasted to register a sharp upturn in 1976 and 1977 (14.9
percent and 14.0 percent increases, respectively), consistent with the
strong growth in the real income of males aged 20 to 34 expected to result
from an upturn in the business cycle. The growth rate in sales will level
off in 1978 and 1979 when a mild correction in the economy is expected.
This correction will occur because of the monetary policy expected as a
result of an overheating of the economy in 1977. The upturn in motorcycle
sales in 1976 and 1977 will also be facilitiated by an increase in the
growth rate of the demographic base for motorcycle sales. Total male
population (with income) is forecast to increase by 3.1 percent respectively
in 1976 and 1977. This growth rate is expected to decline somewhat in 1978
and 1979.
8-15
-------
1980 and 1981 will see a resumption of growth in the economy with
real incomes of the potential market increasing by 6.4 percent and 4.8 per-
cent respectively. The population growth rate will also increase to 3.0
percent and 3.1 percent respectively. A mild correction in the economy is
forecast for 1982 and 1983, with a cyclical upturn in 1984 and 1985.
Thereon to 1990, the economy and the real incomes of the purchasing age
group will remain relatively flat. From 1982 through 1990, the number of
males aged 20 to 34 is forecast to remain virtually flat. Sales of motor-
cycles will basically follow this cyclical pattern. A plateau for sales
growth will be reached around 1985, given the current market structure for
motorcycles. Figure 8-4 shows the history and forecast for total unit
motorcycle sales and real mean income in the age group 20 to 34 years.
It is interesting to note that by 1990, total unit motorcycle
sales will only be 31.5 percent greater than in 1973. Furthermore, despite
the impressive gains for motorcycle sales forecast for 1976 and 1977, the
1973 level of 1,522,354 units will not be reached until 1981.
With the assumption of average unit motorcycle prices increasing
by 7 percent per year, total motorcycle revenues will reach the 1973 level
by 1976. By 1990, the total motorcycle market is forecast to be one of
$7.0 billion. This is shown in Figure 8-5.
Forecasts for on-road, off-road and combination motorcycle sales
are expected to follow approximately the same growth pattern as total unit
sales from 1978 through 1990. In 1976 and 1977, however, the relative
growth rates diverge significantly, with combination motorcycles showing
the strongest comeback in 1976. Combination motorcycle sale's are forecast
to increase almost 61 percent in 1976, rebounding from its low level of
226,093 units in 1975. This is shown in Figure 8-6.
8-16
-------
FIGURE 8-4
PROJECTED TOTAL UNIT SALES VS. MEAN INCOME, MALES, AGES 20 TO 34
Z
_
:
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r
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72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
YEAR
8-17
-------
PROJECTED TOTAL REVENUE VS. TOTAL UNIT SALES
OQ
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72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
YEAR
FIGURE 8-5
-------
PROJECTED STREET, OFF-ROAD, AND COMBINATION UNIT SALES
1.0-
w
2
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FIGURE 8-6
-------
PROJECTED STREET UNIT SALES VS. TOTAL UNIT SALES
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FIGURE 8-7
-------
PROJECTED OFF-ROAD UNIT SALES VS. TOTAL UNIT SALES
i
i .
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} 8£
1
L
9C
1
YEAR
FIGURE 8-8
-------
PROJECTED COMBINATION UNIT SALES VS. TOTAL UNIT SALES
•
i
i >
IS)
E
I 2-
a
' •
a.
in
tn
(
•
(
> (
1
«
(
• ;
"OTA
L
>
T T T
11 tT
,. 1 1 T
111
(_L
)
(
(
)
> c
) C
) «
A
\
•\ (
y
) (
) <
} C
> <
Occ
) C
iMBIf
) (
JATIC
) C
IN
) C
> (
)
72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
YEAR
FIGURE 8-9
-------
8.2 Impacts on New Motorcycle Demand
8.2.1 Price Increase Impacts
The primary impact on demand for alternative regulatory standards
is expected to be the relationship between demand and unit price increases
that are attributable to the alternative regulatory standards. The DRI
New Motorcycle Demand Model described previously was used to relate de-
mand impacts to the unit price increases shown in Section 6.
Price elasticities are shown in Table 8-14. The elasticities were
calculated at the mean of the independent variable of the historical data
base (see Appendix F). Four possible regulatory levels were studied with
the lead times listed below.
Table 8-14 MOTORCYCLE PRICE ELASTICITY
Displacement
Category
Below lOOcc
100
170
350
750
- 169cc
- 349cc
- 749cc
and above
Street
-.928
-.935
-.967
-.836
-.768
Motorcycle Type
Street/Off-Road
-.867
-.997
-.74
-.912
-.45
Off-Road
-.953
-1.148
Table 8-15 MOTORCYCLE NOISE EMISSION STUDY LEVELS AND
POSSIBLE EFFECTIVE DATES
Date Regulatory Level
(SAE J331a)
January 1978 Promulgation
January 1979 33
January 1981 80
January 1984 78 dBA
January 1988 75 dBA
8-23
-------
The alternative noise standards used in this analysis are expressed
in not-to-exceed regulatory levels. It is assumed, based on available data,
that for each regulatory level manufacturers must design for a level 3 dB(A)
less than the regulatory level, in order to account for production and test
variabilities. In the remainder of this analysis, this level will be re-
ferred to as the design level.
Estimates of reductions in demand are summarized in Table 8-16,
for both nominal and worst cases. Relative reductions in unit demand from
a baseline forecast are shown in order to express the reduction in real
terms. A decrease in motorcycle demand is projected because of the nega-
tive price elasticities for motorcycles that were determined in this study,
and the increase in retail price levels attributable to the implementation
of noise control measures. The projected reductions for each study level
analyzed are shown in Figure 8-16. The data indicate that significant
reductions in demand are expected for sound level standards below 80 dB(A)
(J331a).
The impact of each standard is discussed in more detail below.
83 dBA Regulatory Level, 1979
The baseline demand forecast for all new motorcycles in 1979 is
1,346,000 units, broken down as follows: 1,036,000 street motorcycles, and
310,000 off-road motorcycles. An 83 dBA regulatory level in 1979 (J331a)
is expected to reduce demand by 1.5 percent in the nominal case and 2.0
percent in the worst case in the first year of the standard.
80 dBA Regulatory Level, 1981
This regulatory standard is expected to reduce demand anywhere
from 4.5 percent in the nominal case, to 11.1 percent in the worst case.
The product category with the largest potential impact is street motor-
cycles between 170 to 349cc. Reduction in demand is expected to be 8.8
percent in the nominal case and 20.6 percent in the worst case for this
product category.
8-24
-------
TABLE 8-16
ESTIMATED RELATIVE REDUCTION IN DEMAND FOR NEW MOTORCYCLES
DUE TO NOISE CONTROL REGULATIONS
FIRST YEAR OP EACH STANDARD
CATEGORY ^^
RELATIVE REDUCTIC
1979 1981
REGULATORY LEVEL* : 83 dBA i 80 dBA
Nominal (Expected) Case ,
Street-Legal
99cc and Belov
-
100-l69cc
'
350-7 U9cc
750cc and Above
'
' Off-Road
99cc and Belov
i
: 100-l69cc
i
. 350-7l*9cc»*
All Motorcycles
!
[Worst Case
! Street-Legal
99cc and Belov
100-l69cc
170-3U9cc
'• 350-7l*9cc
750cc and Above
Off-Road
99cc and Belov
100-l69cc
170-3U9cc
All Motorcycles
1.8* ; 5.0*
0.7* 0.7*
1.8* 5.2*
t
2.6* 8.8*
2.0* 1 5.8*
0.5* 1.5*
i
1.5* ! 1.8*
I
0.6*
0.6*
0.1** , ; 1.2*
2.3* 6.5*
—
1.5*
2,2*
1.0*
2.2*
3.1**
2.5*
0.6*
1.1*
0.9*
0.5*
3.0*
2.0*
~
U.5*
13.3*
.1.0*
1U.9*
20.6*
1U.5*
3.3*
3.7*
0.9*
2.5*
1U.8*
11.1*
3N IN DEMAND (*)
1981*
78 dBA
16.2*
1988
75 dBA
U.W
6.6* J17.5*
22.0*
22.5*
15.7*
3.6*
7.2*
6.0*
u.u*
15.7*
-
1U.2*
31. W
8.5*
55.2*
39.2*
27.2*
6.3*
12.7*
7.5*
11.0*
27.3*
26.9*
1*1*. 5*
1*1.2*
29.8*
6.6*
15.6*
15.3*
8.9*
28.5*
-
27.9*
1*1*. 0*
22.1*
76.0*
53.7*
37.6*
8.5*
20.6*
19-2*
15.1*
37.1*
1*6.3*
* Not to Exceed Regulatory Level (SAE J331a).
** Data Analysis Inconcliisive for this Product Category
8-25
-------
OO
2,200
2,100
2,000
1,900
1,800
& 1,700
1,600
s
| 1,500
e i.Uoo
1,300
1,200
•
__
IEGUL
,
i
ITORY
5LL
r-4
—
83.
1977 78 79 80 81 82 83 8U 85 86 87 88 89 90
YEAR
FIGURE 8-10 ESTIMATED REDUCTION IN DEMAND FOR NEW MOTORCYCLES DUE TO NOISE REGULATIONS
-------
78 dBA Regulatory Level, 1984
A 78 dBA standard in 1984 could reduce the baseline forecasted
demand by 14.2 percent in the nominal case, and by 26.9 percent in the
worst case. The product categories that would be affected the most would
be street-legal motorcycles between 100 to 169cc and 170 to 349cc. These
categories experience reductions up to 55.2 percent in the worst case.
Apparent reasons are that motorcycles in these categories experience the
greatest relative price increase, and are the most sensitive to price
changes (they have greater price elasticities). The street motorcycles,
750cc and above are expected to have the least severe impact: 3.6 percent
reduction in the nominal case and 6.3 percent in the worst case. These
are the least sensitive to price increases.
75 dBA Regulatory Level, 1988
A 75 dBA regulatory level in 1988 could reduce baseline forecasted
demand by 28 percent in the nominal case and 46 percent in the worst case.
Again, street-legal motorcycles between 100-349cc would be affected most,
and street motorcycles in the largest displacement class would be affected
least. This is a reasonable result, because it is expected that most motor-
cycles will require a major model change to comply with 75 dBA regulatory
levels. Major model changes would tend to impact smaller models more
adversely.
8.3 Impacts on Demand for Products and Service
8.3.1 Historical Aftermarket Sales and Trends
The motorcycle aftermarket represents sales of motorcycle replace-
ment parts, accessories, apparel and services. A broader definition of the
aftermarket would include motorcycle insurance, and miscellaneous items
such as consumer publications, advertising and so forth. The aftermarket
has experienced extremely rapid gorwth. For the broader definition, after-
market sales in 1975 were estimated1 to be $1.8 billion, an increase of
approximately 20 percent over 1974. For the two years prior to 1974, sales
increased an average of 40 percent per year, the market more than doubling
in the past four years? Table 8-17 provides estimated aftermarket sales
for the period 1972 to 1975.
lData for aftermarket sales and growth trends are approximations because
motorcycle aftermarket industry is relatively new and no organized data
collection effort has been made. Most of the detailed data available is
for calendar year 1974.
2Frost and Sullivan "Motorcycle Original Equipment and Aftermarket Study
Announcement", April 1975.
8-27
-------
Table 8-17 AFTEEMARKET SALES GROWTH
Year
1972
1973
1974
1975
Aftermarket
Sales
(Millions of $)
764
1,070
1,500
1,810
Percentage Increase
Over Previous Year
-
40%
40%
20% (E)
Total Number
of Motorcycles
(Millions of Units)
5.4
6.2
7.0
Sources: 1. The 1974 data point obtained from Ziff-Davis Publishing
Company, "Motorcycle Aftermarket Study".
2. Growth rate estimates from Frost and Sullivan "Motorcycle
Original Equipment and Aftermarket Study Announcement".
(E) Estimate provided by Motorcycle Dealer News.
The total aftermarket is being stimulated by the growing base of
motorcycle owners, improved advertising and merchandizing, new products,
more affluent and sophisticated riders, and the trend toward using motor-
cycles for basic transportation. The growing base of motorcycles is
particularly important: Figure 8-11 shows the correlation between sales
and number of motorcycles in use.
A Ziff-Davis Motorcycle Aftermarket survey taken early in 1975
indicated that approximately 85 percent of all motorcycle/mini cycle owners
bought replacement parts, accessories, or apparel items in the motorcycle
aftermarket. Twenty-two percent of these owners spent more than $100 for
their purchases. On the average, each owner spent $86 for these items,
broken down as follows: $54 for replacement parts and accessories, $32
for clothing.
Ziff-Davis Publications, "Motorcycle Aftermarket Study".
2Ibid.
8-28
-------
oo
O
Q
UJ
UJ
^
o:
2,500
2,000
1,500
1,00.0
500
1974
:1973
4 5 6 7 8 9 10 11 12
TOTAL NO. OF MOTORCYCLES IN USE (MILLIONS)
FIGURE 8-11 AFTERMARKET SALES VERSUS TOTAL NUMBER OF FULL-SIZED
MOTORCYCLES IN USE
REFERENCE: TABLE 8-17
8-29
-------
A detailed breakdown of 1974 motorcycle afteonarket sales
determined in the Ziff-Davis Study is shown in Table 8-18. The market for
exhaust system products, which was $30.6 million in 1974, will be particu-
larly impacted by the establishment of motorcycle noise control standards.
Detailed data for exhaust system purchases by motorcycle owners is shown
in Table 8-19. This data indicates that 616,000 buyers (8.8 percent of
all motorcycle owners) purchased 1.4 exhaust system products (mufflers,
expansion chambers, etc.), and spent an average of $50 for each purchase,
or $35 per unit. Most of the exhaust system products (63 percent) were
bought from dealers.
8-30
-------
Table 8-18 MOTORCYCLE INDUSTRY AFTERMARKET SALES, 1974
1974
Annual Sales*
Item (Millions of Dollars)
Replacement Parts and Accessory Items 400
Air Filters 5<9
Brake/Clutch Levers 9^7
Cables 12!l
Cafe Racing Kits 4^1
Carburetors 8^7
Chain Lubricants 7.9
Cleaners and Waxes 3)3
Custom Seat 12^9
Drive Chain 18 !l
Exhaust System Products 30 i 6
Fairings 29.2
Fenders 6.6
Gas Tank 9 Q
Hop-Up Kit 11.'2
Lubricants (other than chain) 14.1
Luggage Rack 13.5
Mirrors 5.8
Replacement Tires 55.6
Saddle Bags and Tote Boxes 12.0
Shock Absorbers 6.8
Side Cars 14.7
Sissy Bars 16.4
Spark Plugs 24.6
Specialty Wheels 13.4
Sprockets 16.7
Tools 31.4
Windshields 5.2
Apparel
Service Receipts/Repair
Insurance
Miscellaneous (Consumer Publications, etc.)**
Total 1,508
Source: Ziff-Davis Publications Motorcycle Aftermarket Survey
**Energy and Environmental Analysis, Inc., "Economic Assessment of
Motorcycle Exhuast Emission Regulations".
8-31
-------
Table 8-19
EXHAUST SYSTEM SALES
Purchased New in Past 12 Months
Total Number of Buyers
Average Number Purchased
Total Units Purchased
Average Amount Spent (Total)
Total Dollar Volume
Exhaust
System
Products
8.8%
616,000
1.4
862,000
$49.73
$30,633,000
Where Purchased
Dealer where cycle bought
Other motorcycle dealer
Motorcycle accessory shop
Chain/department store
Discount auto center
Mail order
Other
Not stated
22.2%
41.3
25.0
1.0
7.7
1.0
4.8
Brand Awareness Among Purchasers
42.3%
Source: Ziff-Davis Publications, "Motorcycle Aftermarket Survey"
*8.8% of 7,000,000 Total Motorcycle Owners.
May add to more than 100.0% due to multiple answers.
8-32
-------
Estimated aftermarket sales in 1975 are shown in Table 8-20 The
estimates are based on a 20 percent growth projection of 1974 aftermarket1
sales. Each of the components is discussed in more detail in the followinq
paragraphs. y
Table 8-20 MOTORCYCLE INDUSTRY AFTERMARKET SALES, 1975
Replacement Parts and Accessories
Clothing
Servi ce/Repairs
Insurance
Miscellaneous
Total
1975 (Est.)
480
268
540
462
60
1,810
Percent
of Total
27%
15%
30%
25%
3%
100%
Note: This estimate based on 20 percent growth projection of 1974 after-
market sales indicated in Ziff-Davis Motorcycle Aftermarket Survey.
Replacement Parts and Accessories
The market for parts and accessories in 1975 was estimated at $480
million, which represents approximately 27 percent of aftermarket sales.
These aftermarket items are generally purchased for performance, styling,
functional or maintenance purposes. Performance and styling are particu-
larly significant—exhaust system products, mechanical parts and hop-up
kits are big sellers in this category. Sales of styling/functional items
that appeal to riders of large street touring motorcycles, such as fair-
ings, windshields, saddle bags and tote-boxes are increasing significantly
as the result of the indicated growth in this type of motorcycle. Any
change in the demand for replacement parts and accessories will directly
affect aftermarket manufacturers, distributors and retail outlets such as
dealers, accessory shops, discount stores and mail order firms.
Motorcycle Dealer News
8-33
-------
Apparel
Sales of apparel (including helmets) were estimated to be almost
$270 million in 1975. The same manufacturers, distributors and retail
outlets that are affected by changes in the market for replacement parts
and accessories will be affected by changes in the market for apparel.
Service/Repairs
Service and repair receipts totaled an estimated $540 million in
1975. Service revenues are increasing principally because of the larger
base of motorcycles in use. Service receipts primarily affect dealers,
since on the average these receipts make up 15 percent of each dealer's
revenue.
Insurance
Motorcycle owners paid an estimated 462 million dollars for
insurance premiums in 1975. Average premium for motorcycle owners pur-
chasing insurance is in the $90-100 range for liability and comprehensive
coverage. Cost generally varies with motorcycle size. Changes in the
demand for motorcycle insurance will have very little effect on the motor-
ized vehicle insurance industry, since it is a very small proportion of
total underwriting. However, there are a few companies that specialize
in motorcycle insurance and these companies will be significantly affected
by actions affecting motorcycle insurance revenues.
Miscellaneous
Miscellaneous includes revenues from motorcycle publications,
books, schools and consultants.
Aftermarket Demand Considerations
Because of its rapid growth in recent years, future aftermarket
sales are particularly difficult to forecast since extrapolation of his-
torical data may lead to unrealistically optimistic projections. However,
one of the key determinants of future aftermarket sales will be the annual
sales of new motorcycles. New motorcycles contribute to the total number
of motorcycles in use, which in turn is closely related to aftermarket sales
(refer to Figure 8-11). Figure 8-12 shows the relationship of new motor-
cycles and total number of full sized motorcycles in use for th3 period
1967-1974. There is growth potential for aftermarket sales as long as
the total number of motorcycles in use increases. The baseline forecast
for new motorcycles indicates that this will continue to occur (as long as
the relationship between new motorcycle sales and total full sized motor-
cycles in use shown in Figure 8-12 holds true). The figure shows that in
8-34
-------
67 68 69 70 71 72 73 74
FIGURE 8-12 RATIO OF CHANGE IN TOTAL MOTORCYCLE POPULATION
WITH NO. OF NEW MOTORCYCLES SOLD
TABLE 8-21
TOTAL NO. OF MOTOR-
CYCLES IN USE*
(THOUSANDS OF UNITS)
INCREASE FROM PRIOR
YEAR
(THOUSANDS OF UNITS)
NEW MOTORCYCLE
(THOUSANDS OF UNITS)
CHANGE IN POPULATION
NEW MOTORCYCLES SOLD
YEAR
67
2,790
-
-
68
3,001
211
583
0.36
69
3,309
308
733
0.42
70
4,021
712
1,002
0.71
71
4,779
758
1,238
0.61
72
5,431
652
1,314
0.50
73
6,214
783
1,520
0.52
74
7,099
585
1,180
0.50
'FULL-SIZED MOTORCYCLES
8-35
-------
recent years (1972-1974), for every two new motorcycles added to the total
motorcycle population, one older motorcycle is retired from the population
for a net increase in the total of one.
The forecast for general aftermarket products and services demand
was not quantified, but it is believed that the aftermarket, in general,
will not be affected significantly by regulatory actions as long as the
number of motorcycles in use is increasing. The effect of regulatory
actions is likely to be a slight reduction in the growth rate of demand
over a 5 to 10 year period, as opposed to reductions in the demand level.
In fact, aftermarket sales may increase in the short run as the result of
regulatory actions, since higher prices of new motorcycles resulting from
regulations could provide the incentive to repair and maintain older motor-
cycles for longer periods. Again, this'would be exceptionally difficult to
quantify.
8.3.2 Price Increase Impacts on Demand for Replacement Exhaust Systems
In 1974, 862,000 exhaust system components were sold at an average
price of $35.5 per component. At this time there is no historical data to
use as the basis for demand projections. However, the following considera-
tions should be noted.
A survey of exhaust system manufacturers indicated that one of
the major product classes in the industry is the complete exhaust system
(headers and mufflers) for multi-cylinder 4-stroke street motorcycles.
This type of system dominates the product line for many of the exhaust
system manufacturers.
Data in Table 7-29 shows expected increases in muffler costs
versus regulatory levels, based on an independent cost estimate. This
estimate shows that muffler cost increases from 33% at 83 dBA to 289%
at 75 dBA can be expected for a large "4 into 1" exhaust system. The
revised costs were inserted into the price mark-up structure in Table 7-28,
to obtain the revised price increases shown in Table 7-30. The price of
the equivalent total exhaust system can increase from 9% (83 dBA) to 89%
(75 dBA). A similar procedure was followed for a "2 into 1" system on a
street motorcycle assumed to be between 350 and 749cc.
Demand impacts on exhaust system manufacturers may be severe,
since relative price increases are greater for exhaust systems than for
new motorcycles for equivalent reductions in sound levels. For example,
in order to meet 78 dBA regulatory levels (J331a), a street motorcycle in
the 170-349cc size category might expect a 13.2 percent price increase
in the nominal case, and a 23.1 percent increase in the worst case. By
contrast, a "4 into 1" or "2 into 1" exhaust system might have a price
8-36
-------
increase of 40 to 50 percent/ as a result of, meeting the same 78 dBA motor-
cycle regulatory level. Projected price increases for the same exhaust
system to meet 75 dBA regulatory levels range from 89 to 114 percent.
In addition, an exhaust system manufacturer's success is very
dependent on the styling, performance and tonal quality characteristics of
his product. Impact of changes in these factors on demand cannot be quanti-
fied, but are believed to be extremely significant, perhaps more significant
than price change impacts.
Price elasticities alone, therefore, cannot be used to estimate the
impact of noise regulation on demand for replacement mufflers. Estimates of
reduced demand based on manufacturer estimates are made below (sec. 8.4.2).
8-37
-------
8.4 Total Annualized Costs
Increases in purchase costs and operation and maintenance costs
for each of the study levels represent a stream of costs attributable
to noise control options. Purchase cost increases are incurred at the
time of sale, and operation and maintenance costs are incurred annually
for the life of the product. In order to compare regulatory options for
a given product and between products it is necessary to use a statistic
to characterize this cost stream. The statistic used for all new product
noise regulations is "uniform annualized costs", or more simply, annual-
ized costs. A cost stream over a given period is represented by a uniform
cost stream (annual costs of equal dollar amount) that has the same present
value. That is, the cost stream to be represented is converted to a pre-
sent value using a specified time value of money. This present value is,
in turn, converted to a cash stream of equal units, which, using the same
time value of money, has the same present value. In essence, a cost stream
over a given period is converted to an annuity over that same period.
This statistic, therefore, accounts both for the size and timing of costs
incurred. The individual product purchase cost increases developed in the
previous sections are used to calculate total purchase cost increases in
each year based on particular study levels and assumed effective dates.
The numbers of units sold in each year is adjusted by fehe expected
decrease in demand calculated above. Increased purchase costs are all
in 1975 dollars. Similarly, the increased operation and maintenance
costs developed above are applied to the population of vehicles in any
year (adjusted for decreased demand). Again, these costs are expressed
in 1975 dollars.
8.4.1 Vehicle Annualized Costs
Table 7-25 displays the nominal and worst case estimates for
increases in purchase price expected at the various study levels. The
nominal estimates range up to $336 per motorcycle for the above 750c.c.
street motorcycle class at 75dB(A). Section 8.2 contains the sales fore-
cast at each of the regulatory levels. Four street motorcycle options
are assessed:
Effective Date
Option 1979 1981 1984 1988
I-S
II-S
III-S 83 80 78
IV-S 83 80 78 75
-------
Four off-road motorcycle options are assessed:
Effective Date
Option 1979 1981 1984 1988
I-OR 86 dB(A)
II-QR 86 83
III-OR 86 83 80
IV-OR 86 83 80 78
Ihe options in each category differ only in the ultimate level
considered; all intermediate steps are the same.
The cost stream for each of these options is assessed over a
total 20 year period (up to 1996) to fully account for the costs of the
ultimate level considered. Ten percent is used for the time value of
money.
Operation and maintenance costs are applied to the existing
population in any given year. Street motorcycles are assumed to be effec-
tively retired after six years, off-road motorcycles after four.
For each option, nominal and worst case estimates were calculated.
The annualized purchase cost increase, the annualized operation and
maintenance cost increases, and the total annualized costs of each option
are presented in Table 8-22.
The discount factor tends to de-enphasize the differences in costs
between the final two regulatory options, both for street and off-road
motorcycles. Whereas in any given year, a 75dB(A) street motorcycle
standard would cost about twice as much as a 78dB(A) standard, the uniform
annualized cost is only about 50% larger. These differences can be more
easily seen from the undiscounted costs that would be incurred once an
ultimate level is fully implemented. The fully implemented costs are
shown in Table 8-23. The sales and population figures are normalized to
1976 levels.
8-39
-------
Table 8-22
TOTAL ANNUALIZED COSTS
(Millions of Dollars)
Street Motorcycles
Regulatory Level (dB(A), J331a)
Nominal (Expected) Case 83 80 78 75
Annualized Purchase Costs 25 69 132 179
Annualized O/M Costs _0 33 57 67
Total Annualized Costs 25~ 102 189 246
Worst Case
Annualized Purchase Costs 31 150 237 286
Annualized O/M Costs _0 52 86 88
Total Annualized Costs 31 202 "323 "374
Off-Road Motorcycles
Regulatory Level (dB(A), J331a)
Nominal (Expected) Case 86 83 80 78
Annualized Purchase Costs 0.8 3.0 9.2 15.0
Annualized O/M Costs 0 1.6 2.9 6.0
Total Annualized Costs 0.8 4.6 12.3 21.0
Worst Case
Annualized Purchase Costs 0.8 4.1 15.3 25.0
Annualized O/M Costs 0 3.2 3.6 7.5
Total Annualized Costs 0.8 7.3 18.9 32.5
1975 Dollars
8-40
-------
Table 8-23
FULLY IMPLEMENTED COSTS
1976 Purchase Levels
(Millions of Dollars)
Street Motorcycles
Nominal (Expected) Case
Annualized Purchase Costs
Annualized O/M Costs
Total Annualized Costs
Worst Case
Annualized Purchase Costs
Annualized O/M Costs
Total Annualized Costs
Nominal (Expected) Case
Annualized Purchase Costs
Annualized O/M Costs
Total Annualized Costs
Worst .Case
Annualized Purchase Costs
Annualized O/M Costs
Total Annualized Costs
Regulatory
83
s 12
0
12
•s 14
0
14
Off -Road Motorcycles
Regulatory
86
•s 0.5
0
0.5
is 0.5
0
0.5
Level
80
39
22
61
85
36
121
Level
83
2.0
0.9
2.9
2.7
1.8
4.5
(dB(A),
78
104
43
147
186
66
252
(dB(A),
M
7.5
3.8
11.3
16.0
5.7
21.7
J331a)
]S_
195
80
275
312
105
417
J331a)
78
19.0
5.8
24.8
32.7
7.7
40.4
1975 Dollars
8-41
-------
8.4.2 Af termarket Exhaust Annualized Costs
Af termarket exhaust system prices as a result of noise regulation
will rise due to two factors: inexpensive non-complying systems will be
eliminated, and currently complying systems will become more expensive as
lower levels require greater complexity. Total annualized costs will be
calculated for this second effect only. It is reasonable to assume that
the fractional increase in prices of currently complying af termarket
systems will parallel the fractional increase of OEM systems at the same
level. Based on Table 7-30, the following increases for currently com-
plying (i.e., OEM level) af termarket systems are assumed:
Regulatory Level (dB(A)-J-331a)
83_ J30 78 ^75
Fractional Increase in Price 10% 25% 50% 100%
To establish the current price of complying af termarket systems,
prices for current complying systems were compared to OEM replacement
prices. Table 8-24 shows that while some systems for the popular models
are less expensive than stock replacements, others are up to $45 more
expensive. This comparison is complicated by differing system configu-
rations and presence or absence of header pipes. The OEM replacement
price for large motorcycles varies between $100 and $250 with many in
area of $175. With replacement systems for smaller motorcycles factored
in, $125 is a reasonable average for OEM replacement systems. Table 8-24
indicates that many large systems are being marketed at up to 33% less
than OEM systems. Accordingly, $100 will be used as the average current
price o£ complying af termarket systems.
The other factor necessary to compute annualized cost is the impact
of regulation on demand for af termarket systems. Using price elasticity
alone would be unrealistic because it does not account for performance and
styling impacts. In addition, such factors are applicable only for price
rises in a narrow range, which is not the expected case for af termarket
systems. Based on discussions with af termarket manufacturers, the following
fractional reductions in demand are estimated:
Regulatory Level (dB(A)->J-331a)
83 ^0 78 75
Reduction in Demand 30% 40% 50% 60%
8-42
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Table 8-24
PURCHASE PRICE COMPARISON BETWEEN
OEM REPLACEMENT AND AFTERMARKET EXHAUST SYSTEMS
Motorcycle
Honda GL-1000
(muffler only)
Honda CB-750 (4:1)
Honda CB-550 (4:1)
Kawasaki KZ900 (4:4)
H-D XLCH (2:2)
Yamaha RD-350 (2:2)
Exhaust
System
Mfr.
A
B
C*
A
B
C
D
A
B
C
D
E
F
A
B
C
D
E
A
B
A
B
Sound Level
( re stock, J-331a)
-2
+1
-2
-2
+1
0
+1
0
-1
+1
0
0
+2
. -1
0
-1
-2
0
+3
+3
+2
+1
Retail Price (S}
(
-31
-31
-61
-85
-30
-10
-25
-32
-42
+35
+43
-42
+28
-85
-95
-30
-10
-5
-5
+10
+45
+5
re stock)
(2 mufflers
(2 mufflers
(2 mufflers
(4:2)
(2 mufflers
(2 mufflers
(2 mufflers
(4:1)
(4:2)
(4:2)
only)
only)
only)
only)
only)
only)
Suzuki GT750 (3:3)
*Not yet in commerce
+1
-53
8-43
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The increase in purchase price and reduction in demand are combined
to calculate total annualized costs:
Regulatory Level (dB(A)^J-331a)
83 J30 78 J75
Aftermarket Total Annualized Costs ($M) 8.2 16.2 22.0 32.8
8.5 Expected Impacts on Individual Manufacturers
8.5.1 Street Motorcycles
Honda Honda currently produces several models that would meet
an 80dB(A) (F-76a) regulatory level (GL-1000, CB-750F, CB-500T, CB-360T,
XL-250). Honda would be expected to have little difficulty bringing its
entire model line into compliance with this level with no major model
changes. Further reductions to the 78dB(A) regulatory level could be
expected to be accomplished on most models with no major model changes.
Based on EPA's motorcycle noise data base, the CB-550 would require the
most attention. It is expected that, given sufficient lead time, Honda's
expertise in motorcycle quieting would allow it to make the major model
changes (including use of liquid cooling for some models) necessary to
produce a limited number of motorcycle models at the 75dB(A) level. Based
on current levels of the larger models, the CB-750F and CB-500T {no longer
in production) appear to be candidates for achieving this regulatory
level.
Yamaha Based on the current levels of Yamaha motorcycles, it is
expected that most models would be controllable to the 80dB(A) (F-76a)
regulatory level without major model changes. The recently introduced
XS-750 indicates Yamaha's ability to produce large 4-stroke models with
low mechanical noise. At the 78dB(A) regulatory level, it is felt that
several models may require major model changes including liquid cooling,
depending on the mechanical noise contribution to the total vehicle noise.
Even with extensive use of liquid cooling, Yamaha might have great diffi-
culty in producing a large number of models at the 75dB(A) level.
Kawasaki Based on the current levels of Kawasaki motorcycles,
it is expected that most models would be controllable to the 80dB(A)
(F-76a) level without major model changes. The most difficult model would
be the KZ-900 series (now KZ-1000). Due to the particular properties of
this motorcycle, its F-76a level is louder than average for this size
motorcycle in comparison with J-331a. At the 78dB(A) regulatory level
it is felt that major model changes, including liquid cooling, may be
necessary for the larger street motorcycles. Even with extensive use
of liquid cooling, Kawasaki might have great difficulty in producing a
large number of models at the 75dB(A) level.
8-44
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Suzuki Based on current levels of Suzuki motorcycles, it is
expected that most models would be controllable to the 80dB(A) (F-76a)
regulatory level without major model changes. Suzukis generally tested
quieter than average on the F-76 test and the larger motorcycles are
already near this level (GT-750, GT-550, RE-5). Suzuki's recently
introduced 4-stroke models incorporate many quieting features. At the
78dB(A) level, several models may need major model changes. The GT-750
and RE-5 already feature liquid cooling. Even with extensive use of
liquid cooling, Suzuki may have great difficulty in producing a large
number of models at the 75dB(A) level.
AMF/Harley-Davidson
(1) Large Models
Barley-Davidson motorcycles equipped with a California exhaust
system just meet the California 83dB(A) (J-331a) standard. It is apparent
that current Harley-Davidson engine types would need major redesign to meet
an 80dB(A) Federal requirement. All known quieting techniques, perhaps
including liquid cooling, might be necessary at this level. EPA concludes
that there is a reasonable chance that Harley-Davidson models may be able
to achieve an 80dB(A) regulatory level with major redesign in conjunction
with a performance and tonal charateristics penalty that AMF/Harley-Davidson
may feel is damaging from a marketing standpoint. Lead time to accomplish
such major redesign would be a primary issue in Barley-Davidson's ability
to manufacture large motorcycles at this level.
It is clear, however, that levels below 80dB(A) are probably not
achievable with the current engine types. Completely new engine designs
would likely be necessary. Again, lead time for such effort would be a
significent consideration.
It is clear from other manufacturers of large-bore twins, however,
that the 75dB(A) level is essentially unachievable with these designs (see
BMW, Moto Guzzi, Ducati). It is also clear that Barley-Davidson's marketing
position makes it unfeasible for them to switch engine types to the multi-
cylinder designs common to the Japanese manufacturers.
(2) Small Models
Based on current sound levels, the Harley-Davidson 2-stroke models
should be able to meet an 80dB(A) requirement without major model changes.
Major model changes may be necessary at the 78dB(A) level and the 75dB(A)
level may not be achievable.
8-45
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BMW BMW motorcycles tested much quieter than average on the
F-76 test and 80dB(A) is expected to be achievable with little change
to current models. BMW felt levels below 80dB(A) (J331a; 77-78dB(A)
on F-76a for these motorcycles) were unachievable with their large bore,
horizontally opposed twin cylinder engine.
Moto Guzzi, Ducati, Benelli/ MV Agustaf Moto Morini These Italian
manufacturers of large street motorcycles felt that 80dB(A) (J-331a; also
estimated to be 80dB{A) on F-76a) was possibly achievable but that at
levels below 80dB(A) the small fraction of their motorcycles produced for
the U.S. would force them to consider withdrawing from the U.S. market.
NVT Motorcycles (Triumph) NVT felt that 80dB(A) was possibly
achievable on the current Bonneville and Tiger models being produced.
Lower levels would require mechanical treatment beyond their resources to
quiet. It was felt that the Wankel motorcycle under development could be
possibly quieted to 80dB(A). Since mechanical noise is relatively low,
lower levels might be achievable at a great performance loss. Use of
liquid cooling would rob the motorcycle of its desirable features and
would be beyond NVT's severely limited resources.
Can-Am (Bombardier) Can-Am has produced versions of its high
performance off-road and MX motorcycles as enduro models intended for
limited street operation. Such enduro models would be subject both to
EPA air emission and noise regulations applicable to street motorcycles.
The combined effect of these regulations could cause Can-Am to drop these
models from the U.S. market at or below the 80dB(A) level. Bombardier
indicated that the high cost of labor and raw materials in Canada required
continued production of high performance motorcycles in order to compete
with the Japanese.
Bultaco Like Can-Am, Bultaco produces enduro versions of its
high performance off road and MX motorcycles as enduro models intended for
limited street operation. Bultaco is currently struggling to meet the
California 83dB(A) standard. Since Bultaco enduro motorcycles are based
on their off-road versions, major model changes such as liquid cooling
are not feasible. The combined effect of air emission regulations and
noise regulations could cause Bultaco to drop enduro models from the U.S.
market at or below the 80dB(A) level.
Rokon Rokon, the only other U.S. manufacturer with vehicle assembly
in the United States besides Barley-Davidson, manufactures an enduro model
of its MX motorcycle. It is beyond Rokon's resources to meet air emission
standards so these models are likely to' be marketed as off-road only when
the air emission regulations become effective.
8-46
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Other Manufacturers Montesa, KTM/Penton, Carabela and other
manufacturers also manufacture "enduro" models which have been street
legal in some states. Since these manufacturers probably do not intend to
meet air emission standards, they will undoubtedly be sold as off-road onlv
motorcycles in the future.
8.5.2 Off-Road Motorcycles
Honda, Yamaha, Kawasaki, Suzuki All of the major Japanese
manufacturers could use technology developed for their street and combina-
tion motorcycles to meet an 86dB(A) requirement. Given sufficient lead
time, all manufacturers are judged capable of 4-stroke conversion and
mechanical treatment to achieve an 80dB(A) regulatory level for large
off-road motorcycles and a 78dB(A) regulatory level for small off-road
motorcycles. At these levels, however, severe performance impacts can be
expected.
Other Manufacturers Husqvarna, Can-Am, Bultaco, OSSA, Montesa,
KIW, Maico, CZ, Carabela, Hodaka, Rokon and several other manufacturers
produce off-road and conpetition MX motorcycles. Almost all of the manu-
facturers EPA talked with agreed that the 86dB(A) Calfornia standard was
achievable at only a limited performance penalty. The manufacturers
generally felt that 83dB(A) might be achievable at some time in the future
but that consumer shifts to higher performance competition models and user
modifications to restore lost performance would make this effort fruitless.
Since these manufacturers specialize in high performance, their demand
would drop off significantly in comparison to the lower priced Japanese
models below 86dB(A). Between 83 and 80dB(A), most of these manufacturers
would either drop out of the U.S. market or would market competition models
only.
8.5.3 Aftermarket Exhaust Systems
It is estimated that approximately half of the firms currently
making replacement motorcycle exhaust systems will either go out of
business or be forced to switch to alternate product lines as a result
of Federal noise standards. These firms are typically small, low volume
enterprises devoted exclusively to manufacturing motorcycle exhaust
system production, with little or no capability for product design and
development. Other firms currently marketing replacement exhaust systems
may likewise be forced to make major readjustments. Catalog suppliers such
as J. C. Whitney, and other retailers who offer a wide range of automotive
type products may be forced to find new suppliers, or may discontinue
selling exhaust systems entirely. Some firms may resort to copying the
designs of other manufacturers, a common practice at present.
8-47
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The ten to twenty leading firms in the industry are expected to be
able to produce complying systems, although at similar price and perfor-
mance penalties associated with OEM systems. Although total demand for
aftermarket systems is expected to decline, these firms ought to at least
preserve their unit volume as other manufacturers withdraw from the market.
The twenty or thirty other firms that are expected to remain in the after-
market muffler market are expected to experience severe difficulties in
remaining competitive, with profits shrinking to the near break even point.
These expected impacts are based upon the assumption that the
regulations will be effectively enforced at the state level to prohibit
widespread sale and use of systems "designed" for motorcycles manufactured
before the effective date of the Federal regulations, or "competition"
exhaust systems reconfigured by the operator for use on a regulated motor-
cycle.
8.6 Impact on U.S. Employment
Vehicle Manufacturers
Barley-Davidson, Rokon, Kawasaki and a few others are the only
motorcycle manufacturers with assembly facilities in the U.S. Assuming
these manufacturers will stay in the market at any given regulatory level,
their decrease in employment ought to follow the total market decrease
in demand. Based on elasticities developed from historical price-sales
relationships, the following impacts on employment would be expected at
each regulatory level studied: 83dB(A)—50 positions; 80dB(A)—150;
78dB(A)—450; 75dB(A)—880. There is reason to believe, however, that
actual impact would be considerably less. Barley-Davidson, however, is not
expected to be able to produce large motorcycles at the 75dB(A) level.
Barley-Davidson's withdrawal from the market at the 75dB(A) or any other
level would result in a complete loss of its motorcycle-related positions
(approximately 3,300).
Aftermarket Manufacturers
Total employment in the exhaust system manufacturing industry is
expected to follow impact on total demand for those systems. As discussed
above, some firms are expected to increase production but a large number
are expected to be forced out of the replacement exhaust business at any
regulatory level. Using the same assumptions as in Section 8.4.2,
the decrease in exhaust system manufacture employment would be: 83dB(A)—
360 positions; 80dB(A)—480; 78dB(A)—600; 75dB(A)—720. Other aftermarket
manufacturers are not expected to suffer any loss of positions at any level.
8-48
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Distributors/Dealers
Employment amongst dealers and distributors is expected to
decline in proportion to the decreased demand for vehicles and exhaust
systems as a fraction of their total business. With the same assumptions
for decreased demand, the decrease in dealer/distributor employment is
expected to be: 83dB(A)—800 positions; 80dB(A)—1800; 78dB(A)—4000;
75dB(A) —6800 •
Total U.S. Employment Impact
Table 8-25 sums the total expected employment impact at each
regulatory level. Although the levels assessed are for street motorcycles,
complementary off-road regulations are expected to contribute to the total
shown.
Table 8-25
EXPECTED U.S. EMPLOYMENT IMPACTS
Regulatory Level (J-331a)
83 8£ ^8 75
Vehicle Manufacturer 50 150
Aftermarket Exhaust System Manufacturer 360 480
Other Aftermarket Manufacturer 0 0
Dealer/Distributor 800 1800
Other 0 0
Total 1210 2430 5050 8300
These are reductions from current employment levels. Expected
growth in the industry would more than compensate for these losses,
netting a gain in total employment at any regulatory level. Again, these
figures are based on historical prices-sales relationships which at felt to
overestimate the impact. However, the aftermarket exhaust segment of the
total market is expected to suffer a net loss at any regulatory level.
8.7 Regional Impacts
The largest employment impacts are expected to occur at the
dealer/distributor level. Except for a certain amount of concentration in
California and other regions of high motorcycle interest, this impact is
expected to be distributed more or less evenly nationwide. The largest
regional impact is expected to be in Southern California, the location of
8-49
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most of the aftermarket exhaust system manufacturers. Other regional
impacts could occur in Milwaukee, York (Pennsylvania), or Lincoln
(Nebraska) if Harley-Davidson withdrew from the market or Kawasaki closed
its U.S. assembly plant. In each of these regions, however, motorcycle-
related employment is a very small fraction of total area employment.
8.8 Impact on GNP and Inflation
Total annualized cost for the most restrictive regulatory noise
level studied is less than $350 million annually. Since this figure is
considerably less than one-tenth of one percent of the over one trillion
dollar U.S. economy, there is expected to be no impact on the U.S. Gross
National Product or on general inflation as a result of this regulation.
Since motorcycles are not commercial goods, price increases are not passed
along in higher prices for other commodities, and no inflation multiplier
applies.
8.9 Impact on Foreign Trade
The impact of any Federal motorcycle regulation on trade with
Canada or Europe is expected to be negligible. Motorcycles do, however,
account for a significant portion of total U.S. trade with Japan. In
the peak sales year of 1973, the U.S. imported about 1.3 million motor-
cycles from Japan. At an average purchase price of about $1000 per
motorcycle (1973 dollars) 'this represented about $1.3 billion in imports,
almost 14% of the total $9.6 billion in goods imported from Japan that
year. Since 1970, the U.S.-Japan annual balance of trade has fluctuated
between almost $600 million net U.S. imports (1974) to over $400 million
net U.S. exports (1972).
Clearly, any large impact on Japanese motorcycles could affect
this balance significantly. The price elasticities developed above have
an absolute value of less than one at modest price rises, indicating that
a price rise would result in a revenue increase despite falling demand.
However, the price elasticity has an absolute value greater than one for
larger price rises, indicating that net revenue to Japan would decrease
in such a situation. Accordingly, Federal motorcycle noise regulation is
likely to marginally increase or'decrease the value of U.S. imports from
Jauan, depending on the regulatory level selected.
1
Data Resources, Inc.
2 ,
Ibid.
8-50
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SECTION 9
OTHER ENVIRONMENTAL EFFECTS
-------
Section 9
OTHER ENVIRONMENTAL EFFECTS
The primary effect of a motorcycle noise regulation will be to
reduce the number of people exposed to motorcycle noise. There will also
be several secondary effects.
WATER QUALITY
In recent years there has been a general trend away from two-stroke
and toward four-stroke motorcycles for street use; EPA exhaust emission
regulations may accelerate this trend somewhat. Currently off-road motorcycles
are typically two-stroke configurations. Several manufacturers have indicated,
however, that in order to comply with the lower possible study sound level
standards for off-road motorcycles, they may switch to four-stroke configura-
tions, although the Agency's analysis shows no significant cost difference.
Two-stroke motorcycle engines generally employ intake oil injection
for lubrication. One characteristic of this system can be an oily exhaust.
A slight decrease in street surface run off of oil may be realized, and water
quality slightly improved if the number of two-stroke motorcycles is reduced.
ENERGY
Ah increase in fuel economy is expected upon switching from two-stroke
to four-stroke configurations. However, such conversions may be negated to some
extent by the additional weight of heavier mufflers and other sound control
apparatus expected to be required for regulated motorcycles. A five to ten
percent reduction in fuel economy is expected to increase fuel consumption by
10 to 20 million gallons per year, as discussed in Section 6.
*
SOLID WASTE
In general, changes in the amount of raw materials used by motorcycle-
related industries are not expected to be significant, although some slight
increase in such use is foreseen. No change in the amount of solid waste is
expected. The scrapping of old motorcycles should not increase as a result of
noise regulation. In fact, increased motorcycle prices and possible performance
decrements should have, to a small degree, a reverse effect: users may be
encouraged to retain old motorcycles longer.
WILDLIFE
Although there are differing opinions as to the significance of noise
Impact on animals, it is generally agreed that the impact is somewhat detrimental
Therefore, quieting motorcycles may have some beneficial effect on wildlife
and domesticated animals, although.the benefit can not be quantified.
9-1
-------
AIR POLLUTION
Noise regulations are not expected to significantly increase
exhaust emmissions from off-road motorcycles. Noise regulations should
not make it more difficult for manufacturers to comply with street motor-
cycle exhaust emission standards. The relationship between Sound Level
Regulations and Exhaust Emission Control is discussed in more detail in
Section 6.8.
9-2
-------
SECTION 10
REGULATORY ALTERNATIVES
-------
Section 10
REGULATORY ALTERNATIVES
The primary purpose of any proposed sound level regulation would
be to reduce the impact of motorcycle noise on human health and welfare
There are a number of alternative methods of achieving this goal, but the
options of the EPA are limited to those authorized by the Noise Control
Act. Under the provisions of the Act, the EPA may establish sound level
limits for newly manufactured motorcycles and replacement exhaust systems
Also, the EPA may require that products be labeled with information on
their noise emissions. Any standard established by the EPA would preempt
state and local standards, unless such standards are indentical to the
EPA standard.
The five options available to EPA are:
(1) Take no action and emphasize state and local regulation and
enforcement efforts.
(2) Require manufacturers to label the sound emission level of
their product.
(3) Regulate to one or more of the study options evaluated in this
document.
(4) Regulate to either lesser or greater levels than those selected
for evaluation here.
(5) Alter the timing of the proposed regulations.
Each of these alternatives is discussed below, in addition to
alternatives not available to EPA.
EMPHASIZE STATE AND LOCAL REGULATION AND ENFORCEMENT EFFORTS
Even without federal regulation, a slight reduction in nationwide
impact from motorcycle sound levels may occur, due to the sound level
standards recently enacted in the State of California. Since California
comprises a significant portion of the total motorcycle market, motorcycles
are generally manufactured to comply with the State's standards, resulting
in a small decrease in average motorcycle sound levels nationwide.
10-1
-------
An alternative available to EPA, therefore, would be to support
the development of state regulations for new motorcycles, rather than
promulgate Federal standards. Such a policy, however, would allow
manufacturers to market unquieted products in states not having regula-
tions for motorcycles. In the past, for example, several manufacturers
have produced special models for sale only in California. A number of
individual state regulations would futhermore cause a heavier compliance
burden for the motorcycle industry. The need for separate treatment at
the state level is also questionable (given the alternative of uniform
national standards) in view of the fact that a great part of the motor-
cycle noise problem is due to exhaust-modified vehicles. Regulations
aimed at controlling the use of these modified motorcycles are likely
to be more effective in reducing overall noise impact for motorcycles.
The health and welfare analysis in Section 5 of this document shows
clearly that regulation of aftermarket exhaust systems is imperative
to reducing motorcycle noise impact. EPA considered regulating exhaust
systems only, since the analysis does indicate that exhaust modified
motorcycles are a primary source of impact. For instance, a fifty
percent reduction in owner modifications to street motorcycles would
result in the same benefit as a 10 dB reduction in new street motorcycle
sound levels. However, most motorcycles are unmodified; without regula-
tions on new street motorcycles, they will stand out as'the single
loudest traffic noise source when noise emissions of other vehicles are
regulated. In addition, State and local government officials have
indicated that the stationary test procedure and tampering provisions
included in the Federal regulation would be helpful enforcement tools.
Although any Federal regulation would be preemptive, the States will,
in any case, reserve the authority to regulate the use of motorcycles.
These regulatory alternatives include issuing violations for exceeding a
state-established sound level,- restrictions on areas where motorcycles
can be operated, and license fees which could discourage the use of motor-
cycles in general or of certain types of motorcycles. These options are
not available to the Federal government, except for motorcycles used on
Federal land. For example, the U.S. Bureau of Land Management (BLM)
could set sound level standards or restrict motorcycle operations on BLM
lands. This approach could reduce the impact from off-road noise greatly,
since it is estimated that approximately half of all recreational off-road
vehicle use takes place on lands administered by the BLM. These lands
represent 20% of the nation's land area.
EPA considered several alternative methods of dealing with the off-
road motorcycle noise problem. 'Several labeling schemes were evaluated,
as was the option of reserving Federal authority and allowing state and
local governments to establish their own new product regulations.
10-2
-------
It is generally agreed that the fundamental problem with off-road
motorcycles is incompatible land-use, and that reducing the noise from
such vehicles will only help, not solve, the problem. In-use regulation
are the most effective methods of dealing with these incompatible land-
uses. Although progress is being made in some quarters, state and local
officials report great difficulty in getting proper in-use and land-use
requirements established and in properly enforcing them once established.
The fact that off-road vehicles are usually not licensed, that operators
are difficult to apprehend once observed in a violation, and that many of
the offenders are juveniles contribute to these difficulties. Virtually
all state and local officials contacted felt that reduced sound levels
would help the problem and either urged EPA to establish regulatory sound
levels or were establishing new off-road motorcycle sound level limits
themselves.
Since some new off-road motorcycles are extremely loud, any reasonable
Federal standard, with its tampering/ replacement muffler and stationary
labeling provisions, can help to reduce the impact of off-road motorcycle
noise considerably. Provided that Federal regulations do not critically
impair off-road motorcycle performance, EPA has concluded that reduced
sound levels from the majority of unmodified off-road motorcycles are a
necessary complement to state and local in-use and land-use regulation. '
At any level of regulation, however, incompatible land use will continue
to exist, and restrictions on the use of off-road motorcycles in certain
wilderness areas and in residential areas will still be necessary in many
jurisdictions.
The Agency carefully considered the desirability of Federal noise
emission standards for competition motorcycles. Acceleration sound
levels of competition motorcycles are often one hundred decibels or more.
Since several types of competition motorcycles are well suited for off-
road operation, the use of such extremely loud vehicles in desert and
trail environments is considered to be a serious and widespread problem.
One manufacturer suggested that, in conjunction with the vehicle label,
engines or other components of competition motorcycles be of a distinc-
tive color to aid enforcement officials in identifying and controlling
their use off-road.
In addition to the problem of off-road use of competition motor-
cycles, noise generated from racetracks where motorcycle competition
events are held has in a number of cases become a source of considerable
public annoyance in surrounding residential areas. Although Federal
noise regulations for competition vehicles are one approach to solving
this problem, other solutions such as boundary line noise ordinances
or time limit restrictions are available to local authorities. Since
racing motorcycles are disassembled between races, vigorous state and
local action would still be necessary in any jurisdiction with competi-
tion motorcycle noise problem, even if Federal noise standards were
10-3
-------
established. By reserving Federal authority, state and local governments
are free to establish boundary line or vehicle performance standards at
their option.
LABELING
Labeling was considered as an alternative to, or in conjunction with,
Federal sound level limits for both off-road and competition motorcycles.
In either case, it would assist state and local enforcement officials in
determining compliance with applicable laws and ordinances.
Different types of labels may be useful for in-use enforcement
purposes. Labels which bear a motorcycle's sound level as measured by a
simple, stationary procedure can simplify enforcement programs in which
actual testing is performed to determine compliance with a standard. The
presence of a compliance-type label on a motorcycle or exhaust system
could also be used by enforcement authorities as providing evidence that
the vehicle is not violating standards tied to a Federal regulation.
Labels which indicate the sound level (as measured by a specified
test procedure) of a motorcycle or exhaust system could possibly result
in generating an awareness of and a consumer preference for quieter
products.
Competition motorcycles would be labeled as not meeting Federal noise
emission regulations, and for use only in officially-sanctioned closed-
course competition. Labeling of motorcycles and replacement exhaust systems
would advise buyers that the product is sold in conformity.with applicable
regulations, and would also alert the user that the motorcycle possesses
noise attenuation devices which should not be tampered with or removed.
Labeling alone at the Federal level would allow state and local
governments to establish noise emission regulations for new motorcycles in
addition to in-use regulations. However, almost all concerned state and
local officials believed that Federal regulation of new off-road motorcycles
would help to solve the noise problem in their jurisdictions.
REGULATE TO ONE OF THE STUDY OPTIONS
The analysis in Section 5 presents the reduction in impact on human
health and welfare in terms of various levels to which motorcycles might
be regulated. Different regulatory study levels have been examined for
street motorcycles and off-road motorcycles, since the technology for
quieting street motorcycles is not directly applicable to off-road motor-
cycles. Weight and ground clearance requirements for off-road motorcycles
limit the amount of muffling that can be, applied. Liquid cooling which
will probably be necessary for large displacement motorcycles at regula-
tory levels below 80 dB(A), is not feasible for off-road motorcycle due
to the weight and "crashability" constraints.
10-4
-------
The range of off-road motorcycle sound levels is rather wide:
small off-road motorcycles of 170 cc or less have a median acceleration
sound level of about 80 dB(A), while the sound levels of off-road
motorcycles over 170 cc range from 87 to above 90 dB(A). Sound level
reduction treatments for small off-road motorcycles are fairly straight-
forward, with only minor performance decrements. To achieve the same sound
levels in larger off-road motorcycles will result in severe performance
decrements. An additional problem mentioned by both motorcycle users
and some government officials is that there may be an increased tendency
for motorcyclists to either modify their off-road motorcycle or switch
to an unregulated competition motorcycle to counteract severe performance
penalties. For these reasons, EPA has considered establishing two differ-
ent regulatory limits, according to displacement, for off-road motorcycles.
Available technology for such regulation is discussed in more detail in
Section 6. Cost of compliance and economic impact are addressed in
Sections 7 and 8 respectively.
REGULATE TO LEVELS NOT CONSIDERED HERE
The regulatory levels studied in this document were based on the
application of various incremental treatments to the motorcycles. Lesser
sound level reductions would not measureably improve public health and
welfare, and, as indicated by the analysis of available technology in
Section 6 of this document, greater reductions in the sound levels of
motorcycles do not appear to be acheivable with "Best available technology"
as required by the Noise Control Act.
ALTER THE TIMING OF THE REGULATION
Both "normal" and "accelerated" schedules of regulatory lead times
were considered by the Agency. These are indicated in Tables 5-2 and
5-16. The normal lead times were based on a rapid but orderly redesign
schedule for a major manufacturer. Smaller manufacturers are expected
to need accelerated programs to meet these schedules. Accelerated lead
times would require the major manufacturers to redesign many models
simultaneously"with substantially increased research and development
costs: smaller manufacturers may not have the additional research and
design capabilities to meet the accelerated schedule. Since there is
a maximum difference of three years between the two schedules, the
additional environmental benefits are negligible (as discussed in section
5.5.1.
Longer lead times were also considered, since most of the smaller
manufacturers would benefit considerably if given an additional year
or two to acheive the 78 or 80 dB(A) regulatory levels. As discussed
above, the loss of environmental benefits would be small.
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ALTERNATIVES NOT WITHIN THE AUTHORITY OF EPA
There are a number of other strategies which could reduce motorcycle
noise levels but which are not within the present authority of the
Federal government. These strategies include a mandatory reduction in
the sale of motorcycles, a special tax on motorcycles, and a limit on
the sale of motorcycles by permit. Another strategy would be to establish
economic incentives to reduce pollution. For instance, some European
countries apply a graduated tax to products according to the sound level
they produce, in order to provide an incentive to the manufacturers to
produce a quieter product or lose a share of the market.
The proposed Federal sound level regulation is only one of the
several strategies to reduce noise. These strategies may be used to
ccnplement one another, not at the exclusion of each other.
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SECTION 11
ENFORCEMENT
-------
Section 11
ENFORCEMENT
11.1 General. The EPA enforcement strategy applicable to the new
motorcycle noise emission standards will place a major share of the
responsibility on the manufacturers of the new motorcycles for pre-sale
testing to determine the compliance of their products with these standards
and regulations. This approach leaves the manufacturers in control of
many aspects of the compliance program, and imposes a minimal burden on
their business. To be effective, this strategy requires monitoring by
EPA personnel of the tests conducted and actions taken by the manu-
facturers in compliance with these regulations.
The enforcement strategy that will be proposed in the regulations
consists primarily of four parts: (1) Production Verification, (2) Label
Verification for the labeled stationary value, (3) Selective Enforcement
Auditing, and (4) In-use Compliance.
The enforcement strategy for irotorcycle replacement exhaust systems
will place a major share of the responsibility on replacement exhaust
system manufacturers and on original equipment manufacturers for pre-sale
testing to determine compliance with the regulations and standards.
The effectiveness of this strategy will again necessitate monitoring by
EPA personnel of tests conducted and actions taken by manufacturers in
complying with the regulations.
In the development of'the enforcement procedures for motorcycle
replacement exhaust systems several preliminary issues were given careful
consideration. The major issues were: (a) What test procedure can
be required of aftermarket exhaust system manufacturers; (b) Should the
aftermarket be required to meet original equipment production sound
levels or, instead, be allowed to assign their own Sound Level Degradation
Factor in complying with the Acoustical Assurance Period, and (c) What
testing and labeling requirements should be made applicable to "universal"
mufflers.
11.2 Test Procedures. Motorcycle manufacturers are required to
verify compliance with the new product noise emission standard by con-
ducting the acceleration test proposed by EPA. However, it does not
appear at this time to be feasible to require exhaust system manufacturers
to perform all required testing using this procedure. Manufacturers of
replacement exhaust systems have indicated that requiring the use of
the acceleration test procedure for all testing could pose a major
problem, due to the difficulty of acquiring new motorcycles for testing
purposes (although it is not an EPA requirement that the test motorcycle
be a new motorcycle). These manufacturers have indicated, however, that
new motorcycles are readily available from dealers for design purposes,
as long as mileage is not accumulated on the vehicles. The acceleration
test procedure would require some mileage accumulation, hence a stationary
test would be desirable.
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The Agency has investigated the relationship between test results of
the proposed acceleration and stationary test procedures. Test data
indicate that if a replacement exhaust system causes a motorcycle
to emit sound levels higher than original equipment levels on the stationary
short test, then in most cases it would cause the sound levels as measured
by the acceleration test to be increased as well.
The regulations prohibit manufacturers from distributing exhaust
systems into commerce if such systems cause vehicles for which they are
designed and marketed to exceed the applicable Federal standard.
In this way both aftermarket and original equipment manufacturers must
meet the same standard. However, the strategy proposed herein allows
aftermarket manufacturers to demonstrate compliance using the stationary
procedure to show that their exhaust system does not cause the test
vehicle to exceed its labeled stationary sound level. This labeled value
is determined by the original equipment manufacturer using the same
stationary test procedure. If the vehicle exceeds the labeled value, the
aftermarket manufacturer must conduct the acceleration test and demonstrate
that his system does not cause the vehicle to exceed the Federal Standard.
The Agency realizes that there may be instances where an exhaust
system passes the stationary test procedure, but is later determined by .
the Agency to not be in compliance with the standard when tested with the
acceleration procedure. In these cases, the Agency will exercise its
discretion in formulating a remedial order to be issued to the manufacturer
of the replacement system. At a mimimum, however, the Agency would
require that the manufacturer cease further marketing of that system for
the particular model motorcycle until such time as the non-conformity
is remedied.
11.3 Original Equipment Sound Level. The manufacturers of new
product motorcycles and motorcycle replacement exhaust systems are
required to design their products so that they will meet the noise
standard for the period of time specified as the Acoustical Assurance
Period. It has been explained to the Agency that the expected degradation
in motorcycle noise level, if any, will likely be attributable to muffler
system deterioration. For this reason it is resonable to require a
replacement muffler manufacturer to assign a sound level degradation
factor to his exhaust systems to assure compliance with the AAP. The
regulations will not require the aftermarket manufacturer to account
also for the vehicle SLDF as determined by the motorcycle manufacturer,
on the presumption that the vehicle SLDF is predominately exhaust system
related. The SLDF attributable to the remainder of the vehicle is con-
sidered to be nearly zero.
The SLDF concept is employed when conducting the acceleration test
which defines the standard. It is not employed when conducting stationary
sound level test procedures.
11.4 Universal Muffler. A universal muffler is one which is designed
to fit 'many models of motorcycles. If a universal muffler is marketed
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for Federally regulated motorcycles, the manufacturer must show that it
meets the Federal standard for each of these motorcycles. Exhaust system
manufacturers have commented that they do not know how the sound level
performance of their mufflers varies from one model motorcycle to another.
They further maintain that it would not be possible to categorize
motorcycles in order to test a worst case to assure that all other
motorcycle models in that category would meet the standard with the same
replacement exhaust system. Ihe proposed strategy requires testing of
all motorcycle/replacement exhaust system combinations that are marketed.
It is not certain what problems may arise from requiring the universal
muffler to be labeled for those motorcycles for which it is marketed. In
cases where a universal muffler is marketed for only a limited number of
models, labeling may not prove to be a burden to the manufacturer. Where
they are marketed for several models, labeling may be more difficult.
The Agency is considering several alternative methods of dealing with
this situation. One would require manufacturers to list on the label all
motorcycle models for which the muffler is marketed. Another would allow
exhaust system manufacturers to supply the mufflers with different
labels. In this way the manufacturer could include a partial list of
models on each exhaust system.
11.5 Production verification. Production verification (PV) is the
testing by a motorcycle or motorcycle replacement exhaust system manu-
facturer of early production models of a category or configuration
(replacement exhaust systems will be tested by categories only) of the
product, and submitting a report of the results to the EPA. This process,
using the proposed methodology, gives the EPA some assurance that the
manufacturer has the requisite noise control technology in hand and the
capability to apply it to the production process. Models selected for
testing must have been assembled using the manufacturer's normal assembly
process and must be units assembled for sale.
PV does not involve any formal EPA approval or issuance of certi-
ficates subsequent to manufacturer testing. The regulations would
require that prior to the distribution in commerce of any regulated
product, that products must undergo production verification. Responsi-
bility for testing lies with the manufacturer. However, the Administrator
reserves the right to be present to monitor any test (including simul-
taneous testing with his equipment) or to require that a manufacturer
ship products for testing to the EPA's Noise Enforcement Facility in
Sandusky, Ohio or to any other site the Administrator may find
appropriate. The motorcycle manufacturer would be allowed a conditional
and temporary waiver of the PV testing requirement under special circum-
stances such as inclement weather conditions.
The basic production unit selected for testing purposes is a product
configuration or category. Motorcycle manufacturers will be required to
test configurations of their products. Configurations are sets of
vehicles which are grouped together on the basis of parameters which will
most likely affect their noise emission characteristics.
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The motorcycle manufacturer would be required to verify production
products of each configuration. The regulations, however, also allow
manufacturers to group configurations into categories based on engine
parameters and to verify by category. This is done by selecting and
testing the configuration in each category that the manufacturer determines
will have the highest level of noise emissions at the end of its Acoustical
Assurance Period (AAP) (based on tests or on engineering judgment). If
when tested in accordance with the test procedure, that configuration
does-not exceed a sound level defined by the new product standard minus
that configuration's expected noise degradation over the period of its AAP,
then all configurations in that same category are considered product
verified.
Replacement exhaust system manufacturers will be testing exhaust
system categories. A category is a model line of an exhaust system which
is marketed for a particular model of motorcycle. The category is
described by attenuation parameters of the exhaust system and its intended
application. Any exhaust system comprised of different combinations of
these parameters constitutes a separate and distinct category. The
manufacturer is required to production verify each category.
The Administrator reserves the right to test vehicles or exhaust
systems at a manufacturer's test facility using either his own equipment
or the manufacturer's equipment. This will provide the Administrator an
opportunity to determine that the manufacturer's test facility and test
equipment meet the required specifications. If it is determined that the
facility or equipment do not meet these specifications, he may disqualify
them from further use for testing under this subpart.
The Administrator may require that manufacturers submit to him any
product tested or scheduled to be tested pursuant to these regulations or
other untested products at such time and place as he may designate.
If a manufacturer proposes to add a new configuration or category to
his product line, or to change or deviate from an existing configuration
or category with respect to any of the parameters which define a con-
figuration or category, the manufacturer must verify the new configuration
or category either by testing a product and submitting data or by filing
a report which demonstrates verification on the basis of previously
submitted data.
. A motorcycle manufacturer may production verify a configuration or
category at any time during the model year or in advance of the model
year if he so desires. Manufacturers may not, however, distribute
into commerce any products within a configuration or category which have
not been production verified.
Production verification is an annual requirement. However, the
Administrator, upon request by a manufacturer, may permit the use of data
from previous production verification reports for specific configurations
or categories.
Production verification performed on early production models provides
EPA with confidence that production models can conform to applicable
noise emission standards and limits the possibility that non-conforming
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products are distributed in commerce. Because the possibility still
exists that subsequently produced vehicles or exhaust systems mav not
conform, selective enforcement auditing (SEA) testing is also incorporated.
}l'* . Selective enforcement auditing. Selective enforcement auditing
(SEA) is the testing of a statistical sample of assembly line (production)
products from a specified product configuration or category to determine
whether the motorcycle and motorcycle replacement exhaust systems comply
with the applicable noise emission standards.
SEA testing is initiated when a test request is issued to the
manufacturer by the Assistant Administrator for Enforcement or his
designated representative. The test request will require the manu-
facturer to test a sample of products of a specified category or con-
figuration produced at a specified plant. An alternative category or
configuration may be designated in the event that products of the first
category or configuration are not available for testing.
Motorcycle SEA; Noise Emission Standard
Ohis SEA plan employs a technique known as inspection by attributes.
The basic criterion for acceptance or rejection of a batch is the number
of sample products in the batch which fail to meet the standard.
A multiple batch sampling inspection plan will be used on motorcycles
for SEA testing. Multiple sampling differs from single sampling in that
small test samples are drawn from consecutive batches rather than one
large sample being drawn from a single batch. It offers the advantage of
keeping the number of products tested to a minimum when the majority of
such vehicles are meeting the standards.
A batch will be defined as the number of products produced during a
time period specified in the test request. This will allow the Admin-
istrator to select batch sizes small enough to keep the number of
products to be tested at a minimum and still draw statistically valid
conclusions about the noise emission levels of all vehicles in that
category or configuration.
The sampling plans are arranged according to the size of the batch
from which a sample is to be drawn. Each plan specifies the sample size
and the acceptance and rejection number for the established acceptance
quality level (AQL). This AQL is the maximum percentage of products
exceeding the applicable noise emission standard that for purposes of
sampling inspection can be considered satisfactory. An AQL of 10% was
chosen for new motorcycles to take into account some test variability.
The number of failing products in a sample is compared to the acceptance
and rejection numbers for the appropriate sampling plan. If the number
of failing products is greater than or equal to the rejection number,
then there is a high probability that the percentage of non-complying
products in the batch is greater than the AQL and the batch fails.
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Since the sampling strategy involves a multiple sampling plan, in
some instances the number of failures in a test sample may not allow
acceptance or rejection of a batch so that continued testing may be
required until a decision can be made to either accept or reject a
batch.
When a batch sequence is tested and accepted in response to a test
request, the testing is terminated. When a batch sequence is tested and
rejected, the manufacturer must cease introducing these products into
commerce. If the manufacturer desires to continue production and intro-
duction into commerce of the failed configuration (category), he may do
so provided he tests all of the vehicles in that category or configuration
produced at that plant. He may then distribute the individual products
that pass the test.
Regardless of whether a batch is accepted or rejected, failed
products would have to be repaired or adjusted and pass a retest before
they can be distributed in commerce.
The manufacturer can request a hearing on the issue of non-compliance
of the rejected category or configuration.
Since the number of vehicles tested in response to a test order may
vary considerably, a fixed time limit cannot be placed on completing all
testing. The proposed approach is to establish a limit on test time per
product. It is estimated that motorcycle manufacturers can test a
minimum of ten (10) products per day.
Replacement Exhaust System SEA
This SEA plan also employs the inspection by attributes technique.
The basic criterion for acceptance or rejection of an exhaust system
category is the number of failing exhaust systems in the test sample. A
single sampling inspection plan will be used on replacement exhaust
systems for SEA tesing.
The proposed inspection plan defines a rejection number for each
test sample size. The test sample size will be designated by the Admin-
istrator in the test request. The rejection number specifies the number
of allowable failing exhaust systems in a test sample for the established
acceptance quality level (AQL). This AQL is the maximum percentage of
failing exhaust systems exceeding the applicable noise emission standard
that for purposes of sampling inspection can be considered satisfactory.
An AQL'of 10% was chosen to take into account some test variability. If
the number of failing exhaust systems is greater than or equal to the
rejection number, then there is a high probability that the percentage of
non-complying exhaust systems of the specified category is greater than
the AQL and the exhaust system category is considered in non-compliance.
When an exhaust system category is rejected and therefore considered
in non-compliance, the manufacturer must cease introducing these products
into commerce. If the manufacturer desires to continue production and
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introduction into commerce of the failed category, he may do so provided
he proceeds with one of the following options: (1) He tests all of the
exhaust systems in that category produced at that plant and then he may
distribute the individual products that pass the test. (2) If he was
required to conduct the original SEA using the stationary test procedure,
he may elect to conduct an identical.SEA (using the same products) with
the acceleration test to show compliance.
The manufacturer can request a hearing on the issue of non-compliance
of the rejected category.
One of the advantages to this single sampling plan is that tne
number of exhaust systems tested in response to a test request- will not
vary as it does in multiple sampling. Under multiple sampling neither
EPA nor the manufacturer ';ill know the number of required tests to be
conducted to determine acceptance or rejection. The replacement exhaust
system manufacturer, however, knows when he receives the test request the
exact number of products he must select and test to determine compliance.
In some cases the number of products tested under single sampling could
be greater than under multiple sampling. However, since the replacement
exhaust system manufacturer will know how many products he will be
required to test, he is able to plan his complete testing requirements
before he begins testing, and therefore, it is expected that his admin-
istrative burden will be less. Also, under this sampling plan, EPA can
more easily proportion a manufacturer's testing requirements to his
actual production, so as to minimize the burden on his time and business.
A fixed time limit will be placed on completing all testing. It is
currently estimated that replacement exhaust system manufacturers can
test a minimum of five (5) exhaust systems per day if the acceleration
procedure is used or fifteen (15) per day with the stationary test.
One of the problems that replacement exhaust system manufacturers
may have in completing the testing under the fixed time limit will be the
acquisition of motorcycles on which to conduct the acceleration test. It
is expected that no motorcycle acquisition problem will be incurred with
the stationary test. In almost all cases the test request will specify a
particular model motorcycle that will be tested with a particular model
exhaust system. 'Therefore, the replacement exhaust system manufacturer
will, in most cases only have to acquire one particular model motorcycle
to conduct his SEA testing.
11.7 Stationary sound level verification. The labeling scheme
included in these proposed regulations would require that the manufacturer
label each motorcycle at a sound level representative of the 90th per-
cent ile sound level of all vehicles of that class. A class is described
by engine and exhaust system parameters. These regulations do not
specify the amount of testing a manufacturer must conduct to establish
that value but rather require the manufacturer to conduct whatever
testing is necessary to determine it accurately. The manufacturer must
maintain the records and data which were used to determine the class
stationary sound level.
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Every new motorcycle subject to the standards prescribed in this
subpart prior to distribution into commerce shall satisfy the stationary
sound level verification requirements. This requires the manufacturer to
determine a class stationary sound level for each class of motorcycles
and to retain in his files the calculations on which these determinations
were based. In addition, each class must pass a stationary sound level
audit (described in the next section), and the manufacturer must submit
to EPA.a label verification report. Once these stationary sound level
verification requirements are met, the manufacturer may distribute
products of that class into commerce.
11.8 SEA; (Stationary sound level). Selective enforcement auditing
for stationary sound levels is the testing of a statistical sample of
assembly line (production) products from a specified class to determine
whether the products are properly labeled.
One such test must be conducted each year for each class prior to
distribution into commerce for stationary sound level verification.
Additional required testing, if any, will be initiated by a test request
issued to the manufacturer by the Assistant Administrator for Enforcement
or his designated representative. The test request will require the
manufacturer to test a specific number of products of a class produced at
a specific plant. An alternative class may be designated in the event
that products of the first are not available for testing.
The testing plan employs a technique known as inspection by attri-
butes. The basic criterion for determination of compliance or noncom-
pliance of a class stationary sound level is the number of sample
products in the test group which exceed the labeled value.
The proposed inspection plan defines a maximum and minimum number of
vehicles in a sample which may exceed the labeled stationary sound level,
consistent with the requirement that 10% of the vehicles must exceed that
value.
If the number of vehicles exceeding the labeled value is outside of
the acceptable range then there is a significant probability that the
labeled value is not representative of the 90th percentile and the
class is deemed mislabeled and in noncompliance.
It is estimated that motorcycle manufacturers can test a minimum of
thirty (30) products per day during a stationary sound level audit.
The Administrator may require at his discretion that test vehicles
be submitted to him for testing at a site and time of his choice. In
addition, he reserves the right to be present to monitor any testing by
the manufacturer.
11.9 Labeling. These regulations require that motorcycles subject to
them be labeled to provide notice that the product complies with the
noise emission standard and to display the stationary sound level for
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that vehicle. The label shall also contain a notice of tampering pro-
hibitions. These regulations also require that motorcycle replacement
exhaust systems, marketed for Federally regulated motorcycles, be labeled
to provide notice that the product complies with the noise emission
standard and that it should only be used on the motorcycle models speci-
fied on the label. The label shall also contain the full corporate name
and trademark of the manufacturer along with month and year of manufacture.
u-10 Right of Entry and Record Keeping. In this regulatory scheme
where a significant part of the regulatory activity is controlled by
those being regulated, it is essential that EPA personnel have free
access to all aspects of the system in order to determine whether the
requirements of the regulations are being followed and if conforming
motorcycles and replacement exhaust systems are being introduced into
commerce. Such access includes all facets of the testing program required
by_the_regulations, all records, reports, and test results which must be
maintained, and all facilities where test products are present or where
any product to be distributed into commerce is manufacturered, assembled
or stored. The regulations will specify which records and other documents
concerning the testing of production units, must be retained, and for how
long.
The regulations will also provide for a sanction against any manu-
facturer who refuses to allow EPA personnel entry to a facility to
conduct authorized activities. This sanction is in the form of an order
issued by the Administrator to cease distribution into commerce of
vehicles or exhaust systems of the specified category or configuration
that are being manufactured at that facility. The Administrator will
provide a manufacturer the opportunity for a hearing prior to the
issuance of such an order.
In instances where a foreign manufacturer markets its products in
the U.S. or where a domestic manufacturer maintains a manufacturing
facility in a foreign country, the regulations make it clear that
all testing and production facilities, wherever located, are subject to
the same record keeping and inspection requirements. These requirements
are necessary to ensure the integrity of the testing process, and the
conformity of production vehicles and exhaust systems to the regulations.
Tests which are not subject to such requirements cannot be considered
reliable, nor can there be assurance that production facilities not
subject to them are producing products that conform to the regulations.
In addition, to fail to apply these requirements to facilities located
overseas would discriminate unjustly against domestic manufacturers in
favor of their foreign competition.
The regulations will apply even to facilities located in jurisdic-
tions where foreign law forbids the kind of summary inspection they
allow. Though it is well established that American courts will not
order a person to disclose documents or other information located in a
foreign jurisdiction that forbids such disclosure, the reason behind that
rule is to avoid a conflict of laws, and is not applicable here. EPA will
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not attempt to make any inspections which it has been informed that local
law forbids. However, if foreign law makes it impossible to do what is
necessary to ensure the accuracy of data generated at a facility as to
the conformity to design requirements of products produced at it, no
informed judgment that a product complies with the regulations can
properly be made. It is the responsibility of the manufacturer to locate
his testing and production facilities in a jurisdiction where this
situation will not arise.
11.11 Exemptions. The regulations will also outline the procedures by
which EPA will administer the granting of exemptions from the prohibitions
of the Act to various product manufacturers, pursuant to section 10(b).
The substantive scope of the exemption provisions of sections 10(b)(l)
and (2) are defined and procedures whereby exemptions may be requested
are set forth. Exemptions will be granted for testing and national
security reasons only. Export exemptions for vehicles and exhaust
systems manufactured in the United States will be automatically effective,
without request, upon the proper labeling of the products involved.
Testing exemptions must be justified in writing by a sufficient demon-
stration of appropriateness, necessity, reasonableness, and control.
Requests for national security exemptions must be endorsed by an agency
of the Federal Government charged with the responsibility of national
defense.
11.12 In-Use Compliance. In-use compliance provisions are included to
ensure that degradation of emitted noise levels is minimized provided
that the vehicles or exhaust systems are properly maintained and used.
These provisions include a requirement that the motorcycle manu-
facturer provide a noise emission warranty to purchasers (required by
section 6(d) of the Noise Control Act), provide information to the
Administrator which will assist in fully defining those acts which
constitute tampering (under section 10(a)(2)(A) of the Act), and provide
retail purchasers with instructions specifying the maintenance, use,
and repair required to reasonably assure elimination or minimization of
noise level degradation (authorized by section 6(c)(l) of the Act).
Under the warranty provisions, intended to implement 6(d)(l) of the
Act, it is required that the motorcycle manufacturer warrant to
the ultimate and subsequent purchasers that new motorcycles subject to
these regulations are designed, built, and equipped so as to conform at
the time of sale with the Federal noise control regulations. The
manufacturer must furnish this time-of-sale warranty to the ultimate
purchaser in a prescribed written form, which will be reviewed by EPA in
order that the Agency can determine whether the manufacturer's warranty
policy is consistent with the intent of the Act.
The tampering provisions require the manufacturer of the motorcycles
to furnish a list of acts which may be done to motorcycles in use and
which, if done, are likely to have a detrimental impact on noise emissions.
The Administrator will then use this information to develop a final list
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of those acts which are presumed by EPA to constitute tampering. A
statement of the Federal law on tampering, which will include the final
list of acts which constitute tampering as determined by EPA, must be
provided in written form to the ultimate purchaser.
The sections dealing with instruction for proper maintenance, use,
and repair of the motorcycle are intended to ensure that purchasers know
exactly what is required to minimize or eliminate degradation of the
noise level of the motorcycle during its life. A record or log book also
must be provided to the ultimate purchaser in order that the purchaser
may record maintenance performed during the life of the product. Ihe
instructions may not contain language which tends to give the manufacturer
or his dealers an unfair competitive advantage over the aftermarket.
Finally, the regulations will provide for Agency review of instructions
and related language.
The in-use provisions for motorcycle replacement exhaust system
manufacturers are similar to the requirements for motorcycle manufacturers
and require that the manufacturer provide a noise emission warranty to
purchasers, a statement on tampering prohibitions and a warning statement
on use of the product when it is not meeting the prescribed standard.
Under the warranty provisions, again intended to implement 6(d)(l)
of the Act, it is required that the manufacturer warrant to the ultimate
and subsequent purchasers that replacement exhaust systems subject
to these regulations are designed, built, and equipped so as to conform
at the time of sale with the Federal noise control regulations. Ihe
manufacturer must furnish this time-of-sale warranty to the ultimate
purchaser in a prescribed written form.
The tampering provisions require the manufacturer to include a
statement explaining to the ultimate purchaser what tampering is and what
acts are likely to constitute tampering.
The warning statement which the manufacturer is required to provide
to the ultimate purchaser is intended to warn purchasers that if the
system has degraded significantly through use and is no longer meeting
the standard, the owner may become subject to penalties under state and
local ordinances. The warning statement, the statement on tampering
prohibitions and the warranty must be submitted to the ultimate purchaser
with the exhaust system inside any packaging in the format specified by
EPA. If there is no packaging, the information shall be affixed to
the exhaust system such that it will not be accidentally removed in
shipping.
11.13 Acoustical Assurance Period (AAP) Compliance. The motorcycle and
replacement exhaust system manufacturer must design their products so
that the products will meet the noise standard for the period of time
specified as the Acoustical Assurance Period beginning at the date of
sale to an ultimate purchaser.
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EPA does not specify what testing or analysis a manufacturer must
conduct to determine that his vehicle or exhaust system will meet the
standard during the Acoustical Assurance Period of these regulations.
However, the regulations would require the manufacturers to make a
determination regarding the expected degradation and maintain records of
the test data and/or other information upon which the determination was
based. This determination may be based on information such as tests of
critical noise producing or abatement components, rates of noise control
deterioration, engineering judgements based on previous experience, and
physical durability characteristics of the product or product subcomponents.
The mechanism used in the regulations to express the amount of
expected degradation, if any, is the sound level degradation factor
(SLOP). The SLDF is the degradation (noise level increase in A-weighted
decibels) which the manufacturer expects will occur on a configuration or
category during the period of time specified as the AAP. The motorcycle
manufacturer must determine an SLDF for each of his vehicle configurations.
The replacement exhaust system manufacturer must determine an SLDF for
each of his exhaust system categories (motorcycle/exhaust system
combination). As previously explained it will not be necessary for the
replacement exhaust system manufacturer to know the SLDF of the motorcycle
as determined by the motorcycle manufacturer, in determining his own
SLDF. The replacement exhaust system manufacturer is only concerned with
the sound level increase that would occur on a particular motorcycle
due to his own replacement exhaust system.
To ensure that the vehicles or exhaust systems will meet the noise
standard throughout the AAP, they must emit a time of sale sound level
less than or equal to the applicable new product noise emission standard
minus the SLDF (exhaust system manufacturers who use the stationary test
will not be required to take into account the SLDF). In no case shall
this noise level exceed the Federal standard; i.e., a negative SLDF may
not be used. Production verification and selective enforcement audit
testing both embody this principle.
If the product's noise level is not expected to deteriorate during
the AAP when properly used and maintained, the SLDF is zero. If a
manufacturer determines that a vehicle configuration or exhaust system
category will become quieter during the acoustical assurance period,
the configuration or category must still meet the standard on the time of
sale and an SLDF of zero must also be used for that conf iguation or
category.
This strategy for determining whether a product complies for the
AAP, should impose little, if any, additional cost on the manufacturers.
In fact a basic assumption in our analysis has been that the noise level
of a motorcycle which is properly used and maintained will not degrade,
at least not any appreciable amount. With the exception of certain
glass pack mufflers, it is also expected that the majority of replacement
exhaust systems will not degrade significantly during the AAP.
EPA is not dictating that a product's noise level cannot deteriorate
during its AAP, but rather merely requiring that it not deteriorate above
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the standard. It may be that most of the data required to determine an
SLOP will already be in the hands of the manufacturer since this informa-
tion is typically used for general product development work. In any
event, EPA is not now proposing to require long term durability tests to
be run as a matter of course.
11.14 Administrative orders. Section ll(d)(l) of the Act provides
that: "Whenever any person is in violation of section 10 (a) of this
Act, the Administrator may issue an order specifying such relief as
he determines is necessary to protect the public health and welfare."
This provision grants the Administrator discretionary authority to
issue remedial orders to supplement the criminal penalties of Section
ll(a). The proposed regulations provide for orders to: (1) recall for
failure of products to comply with regulations; (2) cease to distribute
products not properly production verified; and (3) cease to distribute
products for failure to test.
In addition, the regulations provide for cease to distribute orders
for substantial infractions of regulations requiring entry to manu-
facturers' facilities and reasonable assistance. Ihese provisions would
not limit the Administrator's authority to issue orders, but give notice
of cases where such orders would in his judgment be appropriate. In all
such cases notice and opportunity for a hearing will be given.
•U.S. GOVERNMENT PRINTING OFFICE : 1.977 0-720-335/6010
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