United States
Environmental Protection
Agency
Office of Noise Abatement
and Control (ANR-490)
Washington, D.C. 20460
December 1980
EPA 550/9-80-217
Noise
oEPA
Regulatory Analysis for the
Noise Emission Regulations for
Motorcycles and Motorcycle
Exhaust Systems
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EPA 550/9-80-217
REGULATORY ANALYSIS
FOR THE NOISE EMISSION REGULATIONS
FOR MDTORCYOiBS AND MOTORCYCLE EXHAUST SYSTEMS
December 1980
U.S. Environijental Protection Agency
Office of Noise Abatement and Control
Washington, D.C. 20460
Permission is granted to reproduce this material without further clearance.
This document has been approved for general availability. It does not consti-
tute a standard, specification or regulation.
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TABLE OF CONTENTS
Page
Number
Section 1 INTRODUCTION 1-1
Section 2 INDUSTRY DESCRIPTION
2.1 Product Definition 2-1
2.2 New Vehicle Manufacturer 2-2
2.2.1 Market Shares and Sales 2-3
2.2.2 Product Lines 2-8
2.2.3 Motorcycle Prices 2-8
2.2.4 Typical New Motorcycle 2-8
Manufacturers
2.3 Afterrnarket Industry 2-26
2.4 Motorcycle Dealers 2-34
2.5 Total U.S. Motorcycle Industry 2-37
Employment
2.6 Motorcycle Warranties 2-38
Section 3 NOISE LEVEL TEST PROCEDURES
3.1 Application and Criteria 31
3.2 Moving Vehicle Test Procedures 3—2
3.3 Stationary Vehicle Test 3—23
Proce du res
3.4 Measurement Distance Substitution 3-33
Section 4 NOISE LEVEL DATA BASE
4.1 Content and Format of the Data Base 4-1
4.2 Test Site, Rider, and Vehicle Variables 4-14
4.3 Data Base Statistical Suninaries 4-18
4.4 Aftermarket Exhaust Systems 4-19
4.5 Noise Levels at the Operator and 4—25
Passenger’s Ear Position
Section 5 EVALUATION OF EFFECTS OF MOTORCYCLE NOISE
ON PUBLIC HEALTH MD WELFARE
5.1 Introduction 5-1
5.1.1 Effects of Noise on People 5—1
5.1.2 Measures of Benefits to PublIc 5—3
Health and Welfare
5.1.3 Regulatory Schedules 5—4
5.2 Description of Traffic Noise Impact 5-4
5.2,1 Street Motorcycles 5-4
5.2.1.1 Current Street Motorcycle 5—7
Sound Levels
5.2.1.2 Noise Emission Levels of 5—13
Regulated Street Motorcycles
5.2.1.3 Motor Vehicle Noise 5—13
5.3 Noise MetrIcs 5—17
5.3.1 Equivalent Sound Level L 5-17
5.3.2 Day Night Sound Level, L 5—18
5.3.3 Sound Exposure Levels, L 5 5—18
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Table of Contents (Continued)
Page
Number
5.4 Fractional Impact Method 5-19
5.5 Health and Welfare Criteria - General 5-19
Adverse Response
5.6 Health and Welfare Criteria - Single 5-24
Event Response
5.6.1 Sleep Disturbance 5-27
5.6.2 Speech Interference 5-29
5.6.2.1 Indoor Speech Interference 5-32
5.6.2.2 Outdoor Speech Interference 5-32
5.6.2.3 Pedestrian Speech Interference 5—32
5.7 Noise Prediction Model 5...33
5.7.1 General Overview of the Model 5-33
5.7.2 Overview of the Noise Exposure 5-35
Predictions: General Adverse
Response
5.7.3 Overview of the Noise Exposure 5-38
Predictions: Single Event
Response
5.7.4 Overview of 1oise Impact 5-40
Estimates: General Adverse
Response
5.7.5 Overview of Noise Impact 5-42
5.7.6 Data Groups 5-42
5.8 Results of Analysis - Street Motorcycles 5-46
5.8.1 General Adverse Response 5_47
5.8.2 Single Event Activity 5-52
Interference
5.9 Analysis of Noise Impact of Motorcycles 5-75
Used Off-Road
5.9.1 Distribution of Off-Road 5-82
Motorcycle Sound Levels
5.9.2 Detectability Criteria 5-85
5.9.3 Off-Road Motorcycle Operations 5-87
5.9.4 Estimate of Current Noise Impact 5-87
5.10 Regulatory Schedules 5-92
5.11 Results of Analysis-Off-Road 5-92
Motorcycles
Section 6 NOISE REDUCTION TECHNOLOGY
6.1 DIagnostic Evaluation of Noise Sources 6-1
6.2 Noise Reduction Technology 6-1
6.3 Impacts of Noise Reduction Technology 6-9
6.3.1 Performance Impacts 6-9
6.3.2 Operation Impacts 6-9
6.3.3 Maintenance Impacts 6-11
6.3.4 Aesthetic Factors 6-12
6.4 Production Variations 6-12
6.5 “Best Available Technology” 6-13
6.6 Lead Times 614
6.7 Deterioration of Motorcycle Noise 6-15
levels
ii
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Table of Contents (Continued )
Page
Number
6.7 Deterioration of Motorcycle Noise 6-15
levels
6.8 Relationship to Air Emission Control 6—16
6.9 Technology to Achieve Noise Levels 6-16
Based on Different Measurement
Methodologies
Section 7 COSTS OF COMPLIANCE
7.1 Unit Cost Increases 7—1
7e1.l Manufacturing Unit Costs 7-5
7.1.1.1 Manufacturer Estimates 7—5
7.1.1.2 Generalized and Independent 7—6
Estimates
7.1.2 Research and Development Costs 7-17
7.1.3 Tooling and Other Manufacturing
Equipment Costs 7—23
7.1.4 Testing & Certification Costs 7-23
7.1.5 Total Weighted Unit Costs 7-37
Increases
7.2 Purchase Price Impacts 7-37
7.3 Replacement Exhaust System Price Impacts 7-45
7.4 Operational Cost Increases 7-45
7.5 Maintenance Costs 7-54
7.6 Costs of EPA Air Emission Requirements 7-54
Section 8 ECONOMIC IMPACT ANALYSIS
8.1 New Motorcycle Sales 8-i
8.1.1 Historical We Motorcycle 8-i
Sales Trends
8.1.2 Sales by Product Category 8—i
8.1.3 Baseline Forecast of New 8-12
Motorcycle Sales
8.2 Impacts on Ne i Motorcycle Demand 8-20
8.3 Impacts on Demand for Products and
Services 8-24
8.3.1 Historical Aftermarket Sales
and Forecasts 8-24
8.4 Total Annualized Costs 8-28
8.4.1 Vehicle Annualized Costs 8-28
8.4.2 Aftermarket Exhaust Annualized 8-32
Costs
8.5 Impact on U.S. Employment 8—35
8.6 Regional Impacts 8-36
8.7 Impact on GWP and Inflation 8-36
8.8 Impacts on Foreign Trade 8-37
8.9 Expected Impacts on Individual 8—37
Manu factu rers
8.9.1 Street Motorcycles 8-37
8.9.2 Off-Road Motorcycles 8-39
8.9.3 Aftermarket Exhaust Systems 8-40
lii
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Table of Contents (Continued )
Page
Nuniber
APPENDICES
A. MOTORCYCLE NOISE EMISSION TEST PROCEDURES A-i
B. TEST SITES AND INSTRUMENTATION B-i
C. PRODUCT IDENTIFICATION AND NOISE LEVELS C-i
D. STATE AND LOCAL NOISE REGULATIONS fl-i
E. FOREIGN MOTORCYCLE NOISE LAWS E-i
F. MOTORCYCLE DEMAND FORECASTING MODEL AND F-i
ESTIMATION OF REPLACEMENT EXHAUST SYSTEM
SALES
G. RELATION BETWEEN STAWDARD TEST METHODOLOGIES G-i
AND REPRESENTATIVE ACCELERATION CONDITIONS
H. ADDITIONAL MOTORCYCLE NOISE LEVEL DATA H-i
I. REFINEMENT OF MOTORCYCLE TESTING PROCEDURE 1-1
J. EXPLORATION OF A STATIONARY TEST INCORPORATING
AN ELECTRONIC IGNITION DISABLE SYSTEM J-l
K. FURTHER STUDY OF THE IGNITION DISABLE DEVICE K-i
L. MOTORCYCLE NOISE ESTIMATED FROM TIME/DISTANCE L-i
MEASUREMENTS DURING ACCELERATION IN URBAN
TRAFFIC SITUATIONS
M. FRACTIONAL IMPACT PROCEDURE M-1
N. NATIONAL ROADWAY TRAFFIC NOISE EXPOSURE MODEL N-i
0. NATIONAL MOTORCYCLE NOISE CONTROL EMPHASIS 0-1
PLAN - SUMMARY
iv
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SECTIO 1
INTRODUCTION
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SECTION 1
INTRODUCTION
Statutory Basis for Action
Through the Noise Control Act of 1972 (86 Stat. 1234), Congress estab-
lished a national policy “to promote an environment for all Americans free
from noise that jeopardizes their health and welfare.” In pursuit 0 f that
policy, Congress stated in Section 2 of the Act that “while primary respon-
sibility for control of noise rests with State and local governments, Federal
action is essential to deal with major noise sources in conu erce, the control
of which requires national uniformity of treatment.” As part of that essen-
tial Federal action, subsection 5(b)(1) requires the Administrator of the
Environmental Protection Agency (EPA), after consultation with appropriate
Federal agencies, to publish a report or series of reports identifying
products (or classes of products) which in his judgment are major sources of
noise. Further, Section 6 of the Act requires the Administrator to publish
proposed regulations for each product identified 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, 1975 published a report identifying new motorcycles as a major
source of noise. 1 Section 6 requires EPA 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 applica-
tion 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 components of
those products which have been identified as major sources of noise. Replace-
ment 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 motor-
cycles.
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 compliance with applicable laws and
ordi nances.
1. Federal Register ; 40 FR 23105, May 28, 1975
1—1
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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 corrtii nation 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.
St udy App roach
In June 1974 EPA published a preliminary study report which examines
motorcycle quieting technology and the costs of applying such technology.
This study provided the Agency with an initial assessment of the feasibility
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.
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 EPASS 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
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 motorcycle dealers. Advance copies of
a draft Notice of Proposed Rulemaking (NPRM) and selected sections of the
_ — or ceN flse,VolurneI, Techonology and Cost Information .
1-2
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supporting regulatory analysis were distributed to manufacturers and inter-
ested government officials several months prior to publication of the NPRM to
allow additional time for analysis and COLtflleflt. 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 1r 1 the Agency.
On March 15, 1978 a Notice of Proposed Rulemaking for Motorcycles and
Motorcycle Replacement Exhaust Systems was published in the Federal Register
(40 FR 10822). Public hearings were held in Anaheim, California, April 28 —
May 1, 1978; in St. Peterburg, Florida, May 5, 1978; and in Washington, D.C.,
May 9, 1978. All coirinents submitted with respect to the proposed regulation
during the public hearings and during the public coninent period have been
given careful consideration. An analysis of these coim nts is included in
this document.
Outline and Sunmary of the Background Locuinent and Appendices
Section 1. Introduction
Section 2. Industry Description. General information on motor-
cycles, motorcycle manufacturers, exhaust system manufacturers, and the
structure of the industry is presented in this section.
Section 3. Noise Level Test Procedures. This section contains
a discussion of existing noise measurement methodologies for motorcycles,
and a presentation of EPA’s final procedure for use in regulatory compliance
testing.
Section 4. Noise Level Data Base. This section presents noise levels
of motorcycles and replacement exhaust systems which were obtained using
various test procedures.
Section 5. Public Health and Welfare Analysis. An analysis of
current iirpacts of motorcycle noise, and impacts expected as a result of
various regulatory options is described.
Section 6. Noise Reduction Technology. A discussion of motorcycle
noise reduction feasability is included in the section. In addition the
various engineering techniques involved in controlling noise from motorcycle
noise subsources are also analyzed.
Section 7. Costs of Car 1iance. 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. Estimates 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.
Appendix A. Motorcycle Noise Level Test Procedures. Texts of the
noise level test procedures discussed in Section 3 are presented in this
appendix.
1—3
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Appendix B. Test Sites and Instrumentation. This appendix presents
descriptions and photographs of the instrumentation and the test site loca-
tions used in performing EPA’s motorcylce noise testing.
Appendix C. Product Identification and Noise Levels. This appendix
includes noise level data developed by EPA on individual motorcycles and
replacement exhaust systems.
Appendix U. A synopsis of State and local laws applicable to motor-
cycle noise.
Appendix E. This appendix includes a summary of foreign motorcycle
noise laws.
Appendix F. Motorcycle and Aftermarket Exhaust System Demand Fore-
casting Model. This appendix describes the econometric models used to
forecast motorcycle and afterrnarket exhaust system demand.
Appendix G. Relation Between Standard Test Methodologies and Repre-
sentative Acceleration Conditions. The assessed relationship between
motorcycle noise levels under rapid acceleration conditions (the official
EPA test procedure) and noise levels under representative unconstrained
traffic acceleration conditions is detailed in this appendix.
Appendix H. Additional Motorcycle Noise 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 investigate tachometer
response characteristics. Operator ear and stationary test data are also
presented.
Appendix I. This appendix describes results of EPA ’s efforts to
develop a sliding scale of closing RPM so that more accurate comparisons
could be made between the noise levels of various motorcycles displacement
classes. Also tachometer log was investigated.
Appendix 3. Exploration of a Stationary Test Incorporating an
Electronic Ignition Disable System. This appendix summarizes a study where
EPA evaluated the use of an ignition disable device for both moving vehicle
and stationary vehicle test procedures.
Appendix K. Further Study of the Ignition Disable Device. Data
are included in this appendix to show results of EPA’s efforts to refine the
ignition disable device and to keep rpm overshoot within acceptable values.
Appendix L. Motorcycle Noise Estimated from Time/Distance Measure-
ments During Acceleration in Urban Traffic Situations. This appendix
summarizes a text program which was undertook by EPA to define motorcycle
acceleration profiles and associated noise emissions as the Vehicle operated
in an urban traffic situation.
Appendix M. Fractional Impact Procedure. The procedure used in
assessing the health and welfare impact and benefits to be derived from
regulating noise emission are summarized in this appendix.
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Appendix M. Fractional Impact Procedure. The procedure used in
assessing the health and welfare i pact and benefits to be derived from
regulating noise emission are summarized in this appendix.
Appendix N. National Roadway Traffic Noise Exposure Model. This
appendix includes a detailed discussion of the National Roadway Traffic Noise
Exposure Model. This discussion encompasses the data, calculations, and
assumptions that underline the model with focus on those details relevant to
considerations of noise emission standards for motorcycles.
Appendix 0. National Motorcycle Noise Control Emphasis Plan - Sum-
mary. This appendix is a summary of the Agency’s plans to assist States and
local governments in developing and implementing programs to control nKtor—
cycle noise.
Docket Analysis. All of the questions, comments, and issues raised in
the public hearings and in written submissions to the docket are addressed in
detail.
1-5
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SECTION 2
iNDUSTRY OESCRIPTION
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SECTION 2
INDUSTRY DESCRIPTION
2.1 ProductIon Definition
For the purposes of the EPA motorcycle noise regulation all motor-
cycles 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
Moped-type street motorcycles
Enduro motorcycles intended for limited street operation
Minicycles intended for street operation
Motor-dri yen scooters
This street motorcycle category encompasses vehicles having the following
characteristics:
Approximately 50 to 1300 cc engines, developing from I to 100 horsepower
Two-stroke, four-stroke and rotary engines
One to six cylinders
Liquid, fan and air cooling systems
Two and three wheels
Light to heavy-weight
Shaft and chain drive
Manual and h ydraulic torque converter automatic transmission
Moped-type street motorcycles are two—wheeled vehicles intended for
use on streets and roads. These vehicles, which are popular in Europe and
Asia and which have been already Introduced into the U.S., have the following
features:
Not more than 50 cc engines
Not more than 2 horsepower
Top speed less than 30 mp.h.
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-
2—1
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course competition events, are considered to be hoff-road” motorcycles.
This off-road motorcycle category includes:
Off-road, trail, and cross—country motorcycles
Enduro motorcycles not intended for street operation
Minicycles not intended for street operation
Trials motorcycles
All-terrain motorcycles not intended for street operation
This off-road category encompasses vehicles having the following charac—
ten sti Cs:
50 to 750 cc engines
Two-stroke and four-stroke engines (great majority two-strokes)
Single cylinder
Air cooled
Two and three wheels
Light—wef ght
Chain drive
Manual, centrifugal clutch and continuously variable (belt) automatic
transmission
For the purpose 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 the labeling provisions of the motorcycle noise
regulation. Closed—course competition events include: short track, dirt
track, drag race, speedway, hiliclint, ice race, and the Bonneville Speed
Trials.
Two and three wheeled tractors are not considered to be motorcycles fo,
the purpose of the EPA motorcycle noise regulation. Also, electric an
battery-powered motorcycles are not subject to the provisions of the regula-
tions.
2.2 New Vehicle Manufacturers
More than 30 different manufacturers from all over the world sell motop-.
cycles in the U.S. Manufacturers described in the Motorcycle Industry’ 5
Council’s 1978 StatistIcal Annual are listed in Table 2-1.
Almost all foreign motorcycle manufacturers have companies in the u.s
distributing their products. The four major Japanese companies have whol1
owned subsidiaries located in Sourthern California. Most of the smaller
2-2
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manufacturers are represented by independent distributing firms who represent
thur brand under contractual arrangements. Distributors are listed in Table
2-1 with the associated manufacturers.
Along with motorcycle manufacturers there are a few other U.S. com-
panies 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 manufac-
turers. Representative companies in this category are:
Company Motorcycle
Nelson Industries Mufflers Harley-Davison
l3riggs & Stratton Engines Heald
Tecumseh Engines Heald
wisconsin Engines Heald
Most of these companies are not entirely dependent on the motorcycle
industry, but sell their products to manufacturers in other industries such as
automobiles, lawn mowers, and snowmobiles.
The remainder of the new motorcycle industry description is oriented
primarily toward the manufacturers of full-sized 2-wheel motorcycles, since
this segment is by far the largest element in the industry in terms of number
of units sold.
2.2.1 ilarket Shares and Sales
The new motorcycle manufacturing segment of the industry is character-
ized by a small 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. Total industry sales figures since 1969 are shown in Figure 2-1.
Available sales and market share data for each of the 10 leading companies are
listed in Table 2-2.
In 1978, the five leading manufacturers (Honda, Yamaha, Kawasaki,
Suzuki and AMF/Harley-Davidson) had 96.4 percent of the market, based on
the number of new iiotorcycles registered. This is only an approximation
because an estimated 30 percent of all motorcycles sold are riot 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 indivi-
dual brands, tne largest share of the market is held by Honda, which had 35.9
percent of the market, followed by Yamaha - 25.9 percent, Kawasaki - 15.0
percent, Suzuki — 13.3 percent, and Harley-Davidson - 6.3 percent.
Pill other amifacturers coinbi ned shared approximately 4 percent of
the market, and none individually had a share 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
2-3
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Table 2—1
YIORCYCLE MANUFAC’IURERS AND DISThIBULORS
W Y
OF
BRAND U • S. DISTRIBUTOR MANUFAC’IURE
AMMEX Apache Linüted Mexico
Arco/E—Z Rider Dialex U.S.
Bajaj Bajaj Arrerica, Inc. India
BMW Butler & Smith — East West Germany
Butler & Smith — West
Bertelli/MOtO Benelli Cosn Dpolitafl Motors Italy
Benelli East, Inc.
BultaCX) BultaOD International Ltd. Spain
Can—AM BolTbardier Corporation Canada
Carabela Ojc le - Kraft Racers, Inc. Mexico
CCM CCM Imports 1w rica England
Ducati Berliner Motor Corp. Italy
Gemini Bulldog Manufacturers Taiwan
Harley—Davidson Harley-Davidson Motor, Inc. U.S.
Heald Heald, Inc. u.s.
Hercules Sachs Motors Corp. of U.S.A. West Germany
Honda Honda Motor Co. Ltd. Japan
Arrerican Honda Motor
Husqvarna Husqvarna Motorcycle Co , Inc. Sweden
Indian Seneca Motorcycle Corp. Taiwan
Itaijet Itaijet U.S.A. Italy
Jawa/CZ AneriCafl Jawa Ltd. Czechoslovakia
K’IM KT 1 Anerica Austria
Kawasaki Kawasaki Heavy Industries Japan
Kawasaki Motors Corp., U.S.A.
Lant)retta Scooter Corp. of An rica Spain
Laverda Slater Brothers Italy
Maico Maico Motorcycles, Inc. West Germany
Maico West
Debenham Imports
Montesa osm po1itan Motors, Inc. Spain
Viva Distributing Co.
Moto Guzzi Berliner Motor Corps. Italy
Premier Motor Corporation
Moto Morini Herdan Corporation Italy
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Table 2—1 (cont.)
i r r
BRAND U.S. DISTRIBUTOR MANUFACTURE
Ossa Ossa Sales Corporation Spain
Puch Steyr Daimler Puch Austria
Rickman Target Products England
Sachs Sachs Motor Corp. of U.S.A. West Germany
Suzuki Suzuki Motor Co., Ltd. Japan
U.S. Suzuki Motor Corp.
Tn—Rod Bletz Industries, mc i u.s.
Triumph Triumph Motorcycles England
Vespa Vespa of America Corp. Italy
Yamaha Yamaha Motor Co., Ltd. Japan
Yamaha Motor Corp., U.S.A.
Sources: 1. “1978 Motorcycle Statistical Annual”, Motorcycle Industry
Council.
2. Discussions with the Motorcycle Industry Council, June, 1980.
3. Individual conversations with motorcycle distributors and
manufacturers, June, 1980.
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Figure 2—1
EST. TOTAL U.S. MOTORCYCLE UNIT SALES
—IN THOUSANDS OF UNITS—
N.)
1600
1400
1200
1000
Boo
600
400
200
0
1969 1970 1971 1972 1973 1974 1975 1976 1977 1978
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Table 2-2
Motorcycle Manufacturer Sales and Market Share Data: 1978
R
A
N
1<
Brand Manufacturer
Location/Mfg.
Location(s)
Approx. Annual
Retail Sales
Range ($M)*
Percentage
of New Regis-
tration**
Cumulative
Percentage
1.
Honda
Japan
500*
35.9
35.9
2.
Yamaha
Japan
350-400
25.9
61.8
3.
Kawasaki
Japan
200-250
15.0
76.8
4.
Suzuki
Japan
150-200
13.3
90.1
5.
Harley-Davidson
U.S.
100-1.50
6.3
96.4
6.
Norton—Triumph
U.K.
10- 20
.8
97.2
7.
BMW
Germany
<10
.6
97.8
8.
Husqvarna
Sweden
<10
.5
98.3
9.
Bultaco
Spain
<10
.3
98.6
* U.S. motorcycle sales only (estimate derived from R. L. Polk registration
data).
** Based on 1978 data for nurther of new motorcycles registered (R. L. Polk
registration data).
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 1978, Kawasaki and Honda market shares declined, while Yamaha, Suzuki, and
Harley-Davidson market shares increased.
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 other four leading manufacturers are estimated to be
between $100 million and $400 million. One manufacturer has annual sales
estimated at between $10 to $20 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 displacement
size are shown in Table 2-3. The Japanese manufacturers are the top four
manufacturers in all categories except the 750 cc, and above category, where
Honda and Harley-Davidson are the leaders.
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2.2.2 Product Lines
There are major differences in the products offered by the manufacturers.
Yamaha and Suzuki are manufacturers that offer models in every category (See
Table 2—4). Yamaha has 30 models and Honda has aPproximately 23 different
models in all size and function categories. Harley-Davidson has 8 models,
all of which are in the large street model category. Most of the other
manufacturers have model lines that are limited to some extent. Many of the
others specialize in large motorcycles, small and medium sized dual-purpose or
off-road motorcycles.
Most models in the large Street motorcycle category and almost all
Honda models have 4—stroke engines. Kawasaki, Yamaha, and Suzuki 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 BMW). A list of engine types by manufacturers is provided in
Table 2—5.
2.2.3 Motorcycle Prices
In general, European motorcycles, particularly in the street motor-
cycle category, have higher retail prices than those of major Japanese
or U.S. brands. Figure 2—3 shows a comparison of prices versus engine dis-
placement size for various street models listed in the N.A.D.A. Motorcycle
Appraisal Guide. In the street category, European manufacturers generally
offer a limited number of models at premium prices.
Price comparison for off-road motorcycles are more difficult because
of the multitude of specialized functions of off-road motorcycles. However,
the Japanese brands are typically 10 to 20 percent less in price for equiva-
lent sized off—road models.
The Secretary of TreaSurY determined in 1978 that Honda, Yamaha, and
Kawasaki had violated Section 201(a) of the 1921 Anti-dumping Act. U.S.
sales prices for these manufacturers were found to be lower than their home
market or third country (market) prices. The revised weighted average margins
on overall sales compared were as follows: Honda, 2.6 percent; Yamaha, 0.82
percent; and Kawasaki, 6.9 percent. However, the U.S. International Trade
Coninisslon determined that ... there is no likelihood of injury or prevention
of establishment of an industry in the United States by reason of sales of
motorcycles from Japan at less than fair value.’ Therefore, no penalties
were im osed on these manufacturers, nor were they forced to increase their
prices.
2.2.4 Typical New Motorcycle Manufacturers
Manufacturers of full sized motorcycles can be classified in the fol
lowing manner:
o Major Japanese Motorcycle Manufacturers
F Motorcycies from Japan, United States InterniETh l Trade Con iis Tö i
Washington, D.C., USITC Publication 923, November 1978.
2-8
-------
Figure 2—2
MAJOR MANUFACTURER’S MARKET SHARE
OF REGISTERED MOTORCYCLES
60-
o — HONDA
o — YAMAHA
— KAWASAKI
50- + — SUZUKI
x — HARLEY-DAVIDSON
— ALL OTHERS
p -] ] O
40
LI
0
I-
30•
C -,
0
20-
— ___
10•- — I
— — 9— — ‘ — A
0- — ___________ ___________ ___________ __________
1972 1973 1974 1975 1976 1977 1978
-------
Table 2—3
Market Share By Product Class*
R S
Minfbi]ces >50 cc
5O 9 TUI6
AT
—
hi KZ
Manufacturer
Pct. Minufacturer Pct. Manufacturer Pct.
1.
Yamaha
48.2 Honda 85.5 Honda 31.6
2.
Kawasaki
19.6 Suzuki 9.0 Suzuki 27.9
3.
Honda
17.2 Yamaha 5.5 Yamaha 20.9
4.
Suzuki
14.9 Kawasaki 18.5
5.
Harley-Davidson .8
Can-Am .2
Bultaco .1
i70-349 cc
>mo cc —____
Al
N Z
Manufacturer
Pct. Manufacturer Pct. Manufacturer Pct.
KE
1.
Yamaha
32.2 Yamaha 37.6 Honda 31.9
2.
Suzuki
23.3 Honda 30.1 Harley—Davidson 21.9
3.
Honda
19.8 Kawasaki 20.6 Yamaha 17.3
4.
Kawasaki
19.6 Suzuki 11.3 Kawasaki 15.5
5.
Harley—Davidson
5.7 Bultaco .4 Suzuki 10.5
6.
Bul taco
.9 BMW .7 BMW 2.0
7.
Can-Am
.5 Moto Guzzi .7
* Market share as determined from R. L. Polk New Motorcycle Registration Data 1978.
Non-registered motorcycles are not accounted for in this tabulation.
2-10
-------
Table 2-4
MOTORCYCLE MA UFACTURERS PRODUCT LINE BY PRODUCT CATEGORY
STREET-LEGAL OFF-ROAD
Under 100- 170-. 350- 750cc Under 100- 170- 350-
MAt1UFACTURER 1000 cc 169 cc 349 cc 749 cc &Over 100 cc 169 cc 349 cc 749 cc
Ammex X
B v1W X X
Benelli/Motto Benelli X X X
Bul taco
Can-Am X X
Carabela x x x
Ducati X
Gemini x
Harley-Davidson X
Heald
Hercules/Sachs X X
Honda X X X X X X X X
Husqvarna X X x
Kawasaki X X X X X X X X
Laverda X X
Montesa X X X X X X
Ossa X X X X
Rickman x
Suzuki X X X X X X X X X
Tn-Rod X
Triumph X
Yahama X X X X X X X X X
Sourcés: Th.A.D.AMotorcyc1e7 6 5 i1 Guide,
First Quarter, 1978.
—. Conversations with individual
distributors and manufacturers,
June, 1980.
2-11
-------
Table 2-5
ENGINE TYPES BY MANUFACTURER
Brand/Manufacturer Engine Type(s )
An iex 2-Stroke
BMW 4-Stroke
Benelli/Moto Benelli 2—Stroke/4--Stroke
Can-AM 2—Stroke
Carabela 2—Stroke
Ducati 4—Stroke
Han ey-Davi dson 2- Strok e/4- Stroke
Hercules/Sachs 2-Stroke
Honda 2-Stroke/4-Stroke
Husqvarna 2-Stroke
Kawasak i 2-Stroke/4-Stroke
Laverda 4-Stroke
Montesa 2-Stroke
Ossa 2-Stroke
Rickinan 2-Stroke
Suzuki 2-Stroke/4-Stroke
Triumph 4-Stroke
Yamaha 2-Stroke/4-Stroke
Sources: - N.A.D.A. Motorcycle/Moped Guide,
First Quarter, 1978.
- Conversations with individual
distributors and manufacturers,
June 1980.
2-12
-------
ENGINE DISPLACEMENT—CC---
Figure 2-3
SUGGESTED RETAIL PRICES OF SELECTED MODELS
VERSUS ENGINE DISPLACEMENT (1977 PRICES)
BMW
- r —
KAWASAKI KZ1000-D1
PRO!7 HARLEY-DAVIDSON FX1200
U)
w
0
0
2
co
U-
0
LU
a:
0
-J
c i :
LU
a:
0
LU
I-
C,)
U i
Q
o
C,)
4000
3500
3000
2500
2000
1500
1000
500
0
I—
(S tlOOE
H
—
HONDA PL_1000 YAMAHA
SUZUKI GS 1000C
HAXS750E
0 TRIUMPH T14OV
1 1
KAWASAKI KZ650S2
-__
HONDA
CB 550K
SUZUKI SP 370
- HODAKA 2 0
-
—
,A
YAMAHA KS 400E
HONDA CB 400T I
I STREET MOTORCYCLES
SOUPCE: N A.DA. MOTORCYCLE/MOPED
L APPRA SAL DATE
I I -I I I—
0
100 200 300 400 500 600 700 800 900
I I
1000 1100 1200 1300
-------
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
A major motorcycle manufacturer is defined as one having U.S. retail
level sales of motorcycles and parts of $100 million or over annually.
Manufacturers with “limited” sales have less than $100 million in U.S. retail
sales annually. Actually, most manufacturers in this category have less than
$10 million in annual retail 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 corn-.
panies with over $100 million in annual U.S. retail sales. There are four
such companies (Honda, Kawasaki, Yamaha, Suzuki) which are all very large
industrial concerns, and motorcycles are a major or significant component
of total company operations. Annual motorcycle production and export for
these companies are listed in Table 2-6. Data indicating the financial size
and strength of these companies are provided in Table 2-7.
There is some variation in the proportionate level of motorcycle—related
sales in each company. Honda 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 Yahama are smaller companies, and have a much larger
proportion (50 percent or more) of their total sales coming from motorcycles.
Table 2-6
JAPANESE MOTORCYCLE MANUFACTURERS
PRODUCTION AND EXPORTS, 1976
Manufacturer
Production
(Units)
Export
(Units)
Percentage
Honda
1,928,576
1,230,797
64%
Yamaha
1,169,175
795,341
68%
Suzuki
832,941
632,233
76%
Kawasaki
284,478
263,760
93%
Total
4,214,170
2,922,131
69%
3öurce: Japan Economic Yea bool, J9II/J9/ i.
2-1 4
-------
-4
0
C-,
C)
m
-Q
Table 2-7
MAJOR MOTORCYCLE MANUFACTURERS FINANCIAL DATA
-4
4
STOCK-
NET HOLDERS WORLD*
SALES ASSETS INCOME EQUITY RANKING
COMPANY COUNTRY INDUSTRY ($000) ($000) ($000) $000 EMPLOYEES 1976 1975 SOURCE
Kawasaki Heavy Japan ShipbuildIng 1,964,628 2,958,589 33,634 368,950 38,410 111 104
Industries Industrial Mach.
Motorcycles
Honda Motor Japan Motorcycles 2,435,632 1,905,803 60,902 402,270 28,218 90 107
Automobiles
Far Machine
BMW Germany Automobiles 1,784,436 949,492 50,792 282,346 30,192 129 161
(Bayerlsche Motern Motorcycles
Werke)
Suzuki Japan Automobiles 613,456 491,391 8,098 102,271 9,000 351 346
Motors Motorcycles
Yamaha Motor Japan Motorcycles 554,234 329,905 7,360 95,806 7,965 386 353
Rec. Vehicles
AP.f/Harley Davidson U.S. Motorcycles 1,229,226 827,411 42,720 341,456 25,152 NA NA 2
Leisure Products
Industrial Products
* Ranked by Sales; excludes U.S. Companies
SOURCE:
1. Fortune Magazine, August 1977 (Fiscal Year 1976 Data)
. Fortune Magazine, May 1973 (Fiscal Year 1977 Data)
-------
Approximately 20 to 40 percept of total Japanese motorcycle production
Is exported to the U.S. Kawasaki S U.S. sales are higher than this average,
while Suzuki’s are somewhat lower.
Characteristics of a major Japanese motorcycle manufacturer are shown in
Table 2-8. On the average, each Japanese firm produces one million motorcy-
cles annually, of which approximatelY 27 percent are exported to the U.S. At
the retail level, these motorcycles are worth approximately $250 million to
$300 million Production capacities of the companies range from 40,000 units
per month and greater.
Several features of Japanese financial practices and economic condi-.
tions 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 are much higher than tn U.S. firms. This makes Japanese
companies more vulnerable in the event of downturns In business activity—-.
large interest expenses can create cash flow problenlc
a central bank (Bank of Japan) that has very strong
Bank of Japan can direct bank loans to companies with fina..
which largely alleviates the hazards associated with high leverage.
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 mean...
ingless due to the difference 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 with U.S. companies.
A factor that may significantly Impact the trade balance between the
U.S. and Japan Is the fluctuating value of the dollar versus the Japanese
yen. For example, the value of the dollar has declined by more than 3Q
percent from 1976 to 1979 (see Figure 2-4). Thus the Impact of the dollar/yea
relationship on motorcycle exports is yet to be determined.
A brief profile of the major motorcycle manufacturers is provided i,
the following paragraphs.
Honda
The Honda Motor Company is located in Tokyo, Japan, and sells auto....
mobiles, motorcycles, and miscellaneous non-vehicular products. The company
earned $60.9 million in 1976 on sales of $2,435 million. Motorcycle sales
accounted for 46 percent of the total sales, automobiles accounted for 3
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 1976, the company manufactured nearly 2
million motorcycles, an estimated 20 to 30 percent of which were exported to
the u.s.
The company has put a strong emphasis on R&D and has a separate whol)
Owned subsidiary, Honda R&D Company, Ltd., which conducts research and
development for both the automobile and motorcycle product lines. In 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, fina ’
2-16
-------
Table 2-8
CHARACTERISTICS OF TYPICAL MAJOR JAPANESE MOTORCYCLE MANUFACTURERS*
U.S. RETAIL SALES RAI JGE
NO. OF FIRMS IN CATEGORY:
ADMINISTRATIVE LOCATION:
MANUFACTURING LOCATI ON:
PRODUCT LINE:
MOTORCYCLE PRODUCT LINE:
TOTAL CORPORATION SALES:
ASSETS:
NET INCOME:
NET PROFIT MARGIN:
STOCKHOLDERS EQUITY:
TOTAL MOTORCYCLE RELATED SALES****
DOLLARS
UNITS
MOTORCYCLE RELATED SALES, U.S.:
DOLLARS
UNITS
MARKET SHARE:
NO. OF EMPLOYEES:
MAXIMUM PRODUCTION CAPACITY
$100 Million +
4**
Japan
J apan ’
Motorcycles, Automobi les,
Recreational Vehicles,
Industrial Machinery
Full line of models for
all product classes
$1,400 Million
$1,400 Million
$28 Million
2%
$242 Million
N .A.
1 Million
$280 Million
0.26 Million
22%
8 ,000
40,000+ Units/Month
Source: Information from Individual companies
N.A. - Not Available
* Based on 1976 data
** Honda, Kawasaki, Suzuki, Yamaha
*** All manufacturing Is done in Japan, Kawasakl has a facility in
Lincoln, Nebraska that assembles certain models
**** Retail level sales
2-17
-------
Figure 2-4
YEN/DOLLAR EXCHANGE RATE
r;Jz
p-.. Li
( )-
350
300
250
200
150
100
50
0
1975 1976
1977 1978
YEAR
1979 1980
-------
cial strength, planning and research commitment arid 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 1 s Engine and Motor-
cycle Group, which provides 20 percent of the corporation’s total sales.
This particular group is located in Akashi, Japan, and manufactures motor-
cycles, 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
number of motorcycles, but exports the highest percentage of its total produc-
tion to the U.S.
Kawasaki has a motorcycle assembly facility in Lincoln, Webraska,
but all engine assembly and most motorcycle assembly is done in Japan.
Approximately 200 employees are involved in the U.S. motorcycle manufac-
turing operations.
The company has a technical research laboratory equipped with so his-
ticated monitoring and diagnostic instruments. A noise research effort
has been in progress for several years, and Kawasaki’s capability in this
area (plant, equipment, personnel) appears to be well established.
Suzuki
Suzuki Motors is a leading manufacturer of motorcycles and lightweight
automobiles with 2-stroke engines. Company sales increased from $467 million
to $613 million between 1970 and 1976, an increase of 30 percent. Profits
during this period declined slightly from $10.9 million to $8.1 million.
Yamaha
Yamaha Motor Company manufactures and sells motorcycles, mopeds, bicyles,
snowmobiles, recreational boats, engines and swimming pools. In addition
the company develops and operates recreational facilities.
A large proportion of the company’s revenue comes from motorcycle
sales. In 1976, the company manufactured slightly over one million motor-
cycles. Sixty-eight percent were exported, and approximately 20 to 30 percent
were exported to the U.S.
Yamaha has 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—Davidson is the only remaining major U.S. motorcycle manu-
facturer. The company was started in 1903, and has specialized in manufac-
turing large touring motorcycles. In 1968, the company was acquired by
2—19
-------
Al1F, Inc., as part of AMF’s extensive diversification effort. In 1977 AMF
earned $42.7 million from sales of slightly over $1.2 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 products in AMF’s 1977 annual sales
indicated tnat motorcycles and other travel vehicles provided $203.6 million
in revenues, or appproximately 17 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 Harley-Davidson product line consists of
eight large touring models, all of which are 1000 cc or more. A sidecar
option is available for the larger models.
A total of 51,000 Harley Davidsons were registered in 1977.2 The
larger models averaged a retail price of $3,200 or more; retail sales for
these models alone were approximately $100 million. Harley-Davidson’s sales
on a unit basis represented a 6.1 percent share of the market in 1977, based
on registration data. Harley-Davidson’s market share on a dollar basis is
somewhat higher, since its product line is oriented toward the larger, more
expensive motorcycles. In 1 78, harley—Davidson had 31.9 percent of the
market for motorcycles 750 cc and over. Sales and financial characteristics
of AMF/ Harley—Davidson are shown in Table 2-9. Harley-Davidson recently
discontinued production of its lightweight motorcycles at their wholly-owned
subsidiary in Italy.
Most people in the motorcycle industry believe that Harley-Davidson has a
unique niche in the market place. duyers of the large Harley-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, Harley-Davidson has increased its market share in
spite of increased competition from major Japanese manufacturers in the large
street motorcycle category.
The strong brand loyalty that was indicated by industry sources to
be characteristic of Harley-Davidson buyers would seem to accord Harley —
Davidson certain advantages. It appears that Harley-Davidson sales are
considerably less sensitive to both price increases and declines in real
income than are other brands.
Large Harley-Davi dsons feature a 1 ongi tudi nal 45 degree V-Twin engine
with common crank pin; a unique design in today’s motorcycle market. This
engine configuration provides Harley—Davidson motorcycles with low center- .
of gravity, narrow profile, and powerful low-end torque. It also features
2 Motorcycle Industry Council, “Manufacturers Shipment Reporting System”
2-20
-------
Table 2—9
Q-IARACTERISTICS OF MAJOR U .3. TORCYCLE MANTJFAC’IURING FIRM
(AMP/HARLEY-DAVIDSON) (1)
CATEGORY: U.S. Motorcycle related sales over
$100 Million annually.
LOCATION: Milwaukee, Wisconsin
CORPORATE ProDUCT LINE: Leisure products (including riotorcycles)
Industrial products and machinery.
N CYIORCYCLE P )DUCT LINE: Milwaukee, Wisconsin and York,
Pennsylvania plants: large touring
rrotorcycles (1,000 cc and 1,200 cc
Y AL CORPORATION SALES: $1229.2 Million
NET INCOME: $42.7 Million
NET P1 JFIT MAF&IIN: 3.5%
ASSETS: $827.4 Million
S]X)CKHOLDER’S EQUITY $341.5 Million
MO’IDRCYCLE AND TRAVEL
VEHICLES SALES $203.6 Mi1lion 2
MCYIDRCYCLE RELATED SALES, U.S.
DDLLARS: $l00+ Million
UNITS REGISTERED (TCYrAL)) 51,000
MARKET SHARE: 6.1%
NO. OF EMPLOYEES, YIORCYCLE 3)
RELATED: 3,700 (as of 979) (
Source: Except where otherwise indicated, AMF Annual Report, 1977.
(1) Harley—Davidson, AMF t s largest manufacturing subsidiary.
(2) Motorcycles sales make up a very large percentage of riotorcycle and
travel vehicle sales, but exact percentage not available.
(3) Cycle News, May 23, 1979.
2—21
-------
low frequency asymmetrical 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 SOundu and
appearance must be retained to preserve demand for Harley—Davidson motor-
cycles.
Engines and parts for the large motorcycles are manufactured in Harley—
Davidson’s Milwaukee, Wisconsin facilities, and are assembled in a York
Pennsylvania plant. Approximately 3,700 people are directly employed in
production of motorcycles, parts, and accessories. Approximately 9,300 people
are indirectly affected to some extent at supplier plants, distribution and
sales locations, and Harley-Davidson dealerships. Harley-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.
From a cost standpoi nt, Harley—Davidson suffers a disadvantage j,
view of the fact that darley-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 allocated
over lesser number of units. This disadvantage is tempered by the fact
that Harley—Davidson has a lesser number of models to manage, and that its
product line is composed of strictly lar je street motorcycles which Can
sustain larger cost increases than smaller models on a relative basis.
However, due in part to vehicle improvement, dealer orders in 198o
have increased to 80,000 units. To meet increasing demand for these motor-
cycles, and to improve efficiency, AMF, since it acquired Harley-Davidson,
has been gradually retooling and automating plant equipment, rearranging
plant layout, and strengthening its engineering operations. For example, the
new five-speed transmission case for the Harley—Davidson FLT Tour Guide can
be built by one aan with automated equipment, while 14 men were required to
build the older four—speed transmission Case. With additional manufacturing
Luprovements, vehicle production could be increased as high as 200,000 Units
per year within the next few years.*
U.S. Motorcycle Manufacturers with Limited U.S. Sales
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
$4 - $5 million range. U.S. employment for the companies ranges from 2 to 34.
employees. The small U.S. company s product line is generally limited t
iinicycles, or small motorcycles (typically less than 135 cc) that are
intended for off-road or dual purpose use. Characteristics of a typical u.s.
company with limited sales is shown in Table 2-10. A brief description of
some of these companies is contained in the following paragraphs.
Dialex (formerly Alexander Reynolds )
Dialex is located in Hackeflsack, New Jersey, and manufactures nhinibjke 5
and go—karts. The ninibikes use Tecurnseh engines.
5 7rce:
2—22
-------
Table 2-10
CHARACTERISTICS OF TYPICAL SMALL U.S.
MOTORCYCLE MANUFACTURERS*
RETAIL SALES RANGE:
NO. OF FORMS IN CATEGORY:
ADMI NISTRATION LOCATION:
MANUFACTURING LOCATION:
PRODUCT LINE:
TOTAL MOTORCYCLE RELATED SALES**
DOLLARS:
UNITS:
MARKET SHARE:
ASSETS:
NET PROFIT MARGIN:
NET WORTH:
NO. OF U.S. EMPLOYEES,
MOTORCYCLE RELATED:
Less than $10 Million
10 — 20 (Est.)
U.S. (Typically Great Lakes area)
Either U.S.. or Foreign
Limited number of specialty models
$5.0 Million
11 ,000
Less than 1.0%
$2 Million
N/A
N/A
20
Source: Information from representative companies.
* 1977
** Almost all companies in this category have all or very large part
of revenues coming from motorcycle business.
N/A - Not Available
2-23
-------
Bletz Industries
Bletz rndustries is located in Mansfield, Ohio, and manufactures Tn—Rod,
a three—wheel vehicle intended for off—road use. The Tn—Road uses Briggs—
Stratton 3, 5, and 8 horsepower engines.
Heald
Located in Benton Harbor, Michigan, Heald manufactures two- and three—
wheel cycles in kit form. The cycles use Briggs and Stratton and Tecumseh
engines. The models are intended for trail and utility purposes (e.g., garden
tractors and dump trucks).
Foreign Motorcycle Manufacturers with Limited U.S. Sales
There are over 30 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 of one
percent of the U.S. market, and is worth approximately $4 million in sales
revenues. The product line is typically limited and concentrated in certain
product categories. For example, many of the Italian companies such as
Ducati, Laverda, Moto Benelli, Moto Guzzl, and Moto Morini, market large
street motorcycles. Characteristics of a typical foreign motorcycle manufac-
turer with limited U.S. sales is shown in Table 2—11.
Descriptions of some of the companies are in the following paragraphs.
Benelli
Moto Benelli Is an established Italian firm that is a subsidiary of
Delomaso Industries. Benelli markets 250 cc, 500 cc, 650 cc and 750 cc
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 motorcycles with horizon-
tally opposed twin cyclinder 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 motorcross motorcycles. Bombardier
makes 10,000 motorcycles per year.
Hercules
Hercules are manufactured by DKW/Hercules, part of the Wankel—Fichtel—
Sachs Manufacturing Group, which is one of German’s largest manufacturers
of motorcycles. The Group Is also a major suppi ier of engines to other
motorcycle manufacturers. 0KW primarily makes enduro and off—road motor—
-------
Table 2-11
CHARACTERISTICS OF TYPICAL FOREIGN MOTORCYCLE MANUFACTURER
WITH LIMITED U.S. SALES*
RETAIL SALES RANGE:
NUMBER OF FIRMS IN CATEGORY:
LOCATION:
PRODUCT LINE:
I4OTORCYCLE PRODUCT LINE:
TOTAL CORPORATION SALES:
ASSETS:
NET PROFIT MARGIN:
NET WORTH:
TOTAL MOTORCYCLE RELATED SALES
DOLLARS:
UNITS:
MOTORCYCLE-RELATED SALES, U.S.
DOLLARS:
UNITS:
1 lARKET SHARE:
NO. OF EMPLOYEES
(U.S. DISTRIBUTORS):
Less than $10 Million
25+
Europe, Taiwan, Mexico, Canada
Motorcycles, Bicycles, Mopeds
Limited number of speciality models
N/A
N/A
N/A
N/A
N/A
20,000
$4 Million (Est.)
4,000
Less than l
40
source: Intormation troin incliviiual U.S. distributors Ot toreign
manufacturers.
N/A — Not Available.
* 1975
2—25
-------
cycles. 0KW also markets a rotary engine model, although production of this
model is relatively limited.
Husgvarna
Husqvarna 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.
Laverda
Laverda is an Italian motorcycle manufacturer that makes large street
motorcycles whose product line is primarily in the 750-1000 cc size range.
Moped-type Street Motorcycles
Moped-type vehicles are street motorcycles intended for use on streets
and roads. These vehicles were first introduced into the U.S. in 1975 after
the National Highway Traffic Safety Administration relaxed its safety stand-
ards so that moped-type street motorcycles similar to the ones sold overseas
could be imported.
Although nine American companies (See Table 2—hA) have entered the
market, most of the moped-type street motorcycles sold in the U.S. are import-
ed. Imports have risen from the 1975 level of 33,136 by 138 percent and 144
percentfor 1976 and 1977 respectively. For the first seven months of 1978 the
number of moped-type street motorcycle imports is 284,494, a 176 percent
increase over the same period in 1977. During 1980 the population of moped..
type street motorcycles is expected to increase to over 1,000,000 vehicles.
Recent Moped sales are estimated by the Moped Association of America
( iAA) as follows:
1975 25,000 Units
1976 75,000 Units
1977 150,000+ Units
1978 250,000 Units
This rapid growth is shown in Figure 2-5. Other Moped characteristics
are suniiiarized in Table 2-12.
2.3 Aftermarket Industry
The structure of the afterr iarket segiiient of the industry is entirely
different from the new motorcycle market segment. The afterinarket industry
is primarily domestic, as compared with the primary product market itself
which has become internationalized. There are an estimated 1500 companies i
2-26
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Figure 2-5
250,000
U.S. MOPED SALES
200,000
150.000
100.000
50,000
C l
YEAR
1975 1976 1977 1978
Source: Moped Association of America
2-21
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Table 2-hA
MOPED MANUFACTURERS AND DISTRIBUTORS
BRAND
U.S. DISTRIBUTOR
COUNTRY OF
MANUFACTURE
AMF Roadmaster
Baretta
Bat avus
Benel ii
Bermuda
Carabela
Casal
Classic
Columbia
Co minu te r
Concord
Co smo
Cuyler
Derbi
E-Z Rider
Fantic
Flying Dutchman
Fox i
Garel ii
Gadabout
H awk
Hercules
Honda
Indian
Jaw a
Kreid 1cr
Mobyl ette
Morini
Motobee
Motron
Moto Guzzi
Murray
Negrini
AMF, Inc.
Baretta of America
Batavus of America
Cosmopolitan Motors
Essex Subaru
Bermuda Bikes, Inc.
Cycle - Kraft Racers, Inc.
Baltimore Cycles, Inc.
Motron Corporation of America
Midstates Appliance
Tiger Cycle Manufacturing
Columbia Manufacturing Co.
Wheelsport Distributing Co.
Columbus Cycle
Cosniopol itan Motors
Cuyler Corporation
Derbi Motor Corp. of America
Dialex
Fantic Moped, Inc.
Flying Dutchman Mopeds
United Moped, Inc.
Agrati-Garelli Corp. of America
American Garelli - West
Yankee Cycle Corporation
American Moped Corporation
Sachs Motor Corp. of U.S.A.
American Honda Motor Company
American Moped Associates
Essex Subaru Moped
American Jawa Ltd.
Kreidler Import Corporation
Motobecane America Ltd.
Herdan Corporation
Motobee Ltd.
Midway Distributing Co.
Premier Motor Corporation
Murray Ohio Manufacturing Co.
Marina Mobili, Inc.
U.S.
Italy
Netherlands
Italy
Belgium
Mexico
Portugal
Italy
Italy
U.S.
Italy
Italy
Spain
U.S.
Italy
U.S.
U.S.
Italy
Italy
Italy
West Germany
Japan
Taiwan
Czechoslovakia
West Germany
France
Italy
Italy
Italy
Italy
U.S.
italy
2-28
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Table 2—hA (cont.)
BRAND U.S. DISTRIBUTOR MANUFACTURE
Pacer Essex Subara Moped Italy
Allied Cycle Distributors
AEON International Corporation
Panther Panther Motorsport Industries U.S.
Peddler 1 s Choice I alsey Distributors Italy
Peugeot Cycles Peugeot (U.S.A), Inc. France
Pryer 3—Wheel Pryer Industries U.S.
Puch Mopeds Midwest Austria
Steyr Daimler Puch of America Corp.
Sachs United Moped West Germany
Sachs Motor Corporation of U.S.A.
Safari Moped Distributors Italy
Motor Bikes Import
Scout Intra Motor U.S.A. Italy
Snark Snark Mopeds, Inc. Italy
Soni Bajaj Scooter Corporation India
Paul Soni of America, Inc.
Sparta Dursor U.S.A., Inc. Netherlands
Sparta/Moby
Tomos U.S. Trade Representatives Yugoeslavia
Tri-Ped American Tri-Ped Corporation U.S.
Yamaha Yamaha Motor Corporation U.S.A. Japan
Source: Individual conversations with moped distributors, June, 1980.
2—29
-------
Table 2-12
MOPED-TYPE STREET MOTORCYCLE CHARACTERISTICS 1
Introduced into the U.S.in 1975
1975 sales: 25,000
1976 sales: 75,000 2 (MAA estimate)
1977 sales: 150,000
1978 sales: 250,000
Features:
(A) 1-2 hp
(B) 50 cc 2—stroke single cylinder engine
(C) Top speed less than 30 m.p.h.
CD) Pedal assisted for acceleration from complete stop
(E) Automatic transmission (centrifgal clutch or direct drive)
(F) Bicycle—type frame, brakes
(6) 60-100 pounds, 120-200 ni.p.g., $300—$500
Noise levels: 3
60-69 dB at 50 feet (full throttle/top speed)
73 dB ISO procedure
Manufacturers
Approximately 24 currently importing to U.S.
Approximately 9 U.S. manufacturers
Markets :
Bicycle Shops 45%
Moped Speciality Shops 30%
Motorcycle Shops and 25%
other outlets
Annual Mileage:
Europe: 2500—3000 miles annually
U.S.: Insufficient experience
State Regulations:
More than 30 states separately define mopeds as a separate
vehicle; remainder classify as motorcycle
Sour i
1. Motorized Bicycle Association.
2. Consumer Reports.
3. Mopeds currently sold in the U.S. and tested by EPA
4. Conversations with individual distributors and
manufacturers, June, 1980.
5. Dealer News.
2-30
-------
the U.S. that are involved to some e tent with manufacturing and distri-
buting 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 eight years.
General Aftermarket Company
Firms in the motorcycle aftermarket industry can be classified as
manufacturers only, manufacturers and distributors, and distributors only.
These companies are not all strictly motorcycle oriented; a significant
nunt er are diversified and involved in other industries. For example, some of
the motorcycle aftermarket manufacturers are large automotive aftermarket
companies which have expanded their operation into the motorcycle market.
Some firms also serve the snowmobile, boating, bicycle and other miscellaneous
industries. In general, the smaller companies in the industry have a large Or
complete dependence on motorcycle products sales, and the large companies have
a relatively small dependence on motorcycle sales. General characteristics
of the aftermarket industry are summarized in Table 2—13.
Exhaust Systems/Components Manufacturers and Distributors
The segment of the after iiarket that will be most directly affected
by noise regulation are companies which manufacture exhaust system pro-
ducts — mufflers, exhaust pipes, expansion chambers, and exhaust headers.
There are over 150 companies in this group who are selling in a 9 arket 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
compete in a crowded market.
Based on a survey of 11 representative firms, companies in the exhaust
system segi 1ent of the aftermarket manufactures 2,500 - 40,000 exhaust systems
and components per year, have annual sales of $100,000 - $1.1 million, and
net 5 to 10 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. Characteristics of exhaust system manu-
facturers shown in Table 2-14 are derived from manufacturer proprietary
i nforrnation.
Typically the president/owner of the company is also the designer
of the exhaust system and components, although one or two people may assist
him in this function. Design emphasis is on styling, performance, and sound;
the priorities are dependent upon individual company philosophies. I Ioise
Motorcycle Dealer tiews.
2—31
-------
Table 2-43
AFTERMARKET INDUSTRY CHARACTERISTICS
Total motorcycle aftermarket sales*
$1.8 Billion
Number of U . S a f te rma rk et ma nu fac tu re rs
550 approximately
Exhaust system afterrnarket sales
$30,663 ,000 retail
616,000 purchasers
862,000 exhaust system products
$49.73 average per purchase
Intake system aftermarket sales
$5,880,000 retail
840,000 purchasers
1,344,000 units
$7.00 average per purchase
*Z ff Iv1j j fl shlng Co., Mof Fcy TeAff rifT tudy - 1974
2-32
-------
Table 2-14
CHARACTERISTICS OF MOTORCYCLE AFTERMARKET
EXHAUST SYSTEM MANUFACTURERS*
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:
flJMBER OF EMPLOYEES, MOTORCYCLE
RELATED:
Afterrnarket Exhaust System
Manufacturer **
90+
U.S., Predominantly California
Mufflers, Expansion Chamber, Headers
$300,000 - $11 Million
$300,000 ***
5 - 10%
N/A
$100,000 — $1.1 Million
2,500 - 40,000
1-3%
10 - 40
Source: Information from sample of representative companies.
* 1975
** Most companies derive most or all of their business from exhaust system
sal e s.
*** Generally 60 to 75 percent of assets is in inventories.
N/A - Not Available
2-33
-------
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.
Estimated market shares replacement parts are presented in Table Uon
Sequester 2—15 and 2-16.
2.4 Motorcycle Dealers
The major retail outlets in the motorcycle industry are dealers, motor-
cycle accessory shops, department store chains, discount stores, mail order
firms and others (e.g., service stations). Some dealers sell new and Us ç
motorcycles, and aftermarket products and services, while other dealers sell
aftermarket products only. Hc ever, most aftermarket parts and accessory
retail sales result primarily from franchised dealers, who are responsible
for 75 to 80 percent of total sales (see table below).
SALES OF MOTORCYCLES, PARTS AND ACCESSORIES
BY TYPE OF OUTLET
OUTLET
PERCENTAG
RETAIL
E OF TOTAL
SALES
Franchised Dealerships
75 - 80
Mail Order
10 - 12
Accessory Shops
6 - 8
Department/Discount Stores
6 - 8
Other
1-2
Source: Frost and Sullivan, “Motorcycle Original Equipment and Aftermarket
Study Announcement,” April 1975.
2-34
-------
Table 2—15
MANUFACTURERS OF MOTORCYCLE ACCESSORY ITEMS
*
CURRENT/FUTURE MARKET ANALYSIS
EXHAUST SYSTEMS
CURRENT SHARE OF FUTURE SHARE OF
MAJOR BRANDS MARKET PERCENT MARKET PERCENT
Honda 21.0 11.0
Hooker 13 .0 30.0
Yamaha 5.0 -
Suzuki 4.0
Torque 4.0 9.0
Bassani 3.0 7.5
Dunstall 2.0 1.5
Kawasaki 1.5 —
Rupp .5 -
All others 46.0 41.0
Table
2-16
*
EXPANSI ON
CHAMBERS
CURRENT SHARE OF FUTURE SHARE OF
MAJOR_BRANDS MARKET PERCENT MARKET PERCENT
Hooker 22 32
Bassani 20 26
Yamaha 8 3.5
Suzuki 4
J R 3 3.5
Kawasaki 2 2.0
Honda 2
All others 39 33
* T omp ansi
2-35
-------
There are an estimated 7,900 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 that offer a small specialized product line; the
typical multiple brand dealer represents more than one of these manufacturers
to expand the variety of models he can sells. Estimated 1977 U.S. retail
sales by franchised motorcycle dealers is $3.4 billion dollars. A further
breakdown is shown in Table 2-17.
Table 2-17
ESTIMATED 1977 U.S. RETAIL SALES BY FRANCHISED MOTORCYCLE DEALERS
New Motorcycle Sales $1.49 billion
Used Motorcycle Sales .37 billion
Accessory Sales .44 billion
Service Sales .43 billion
Parts Sales .47 billion
Other . 20 billion
TOTAL $3.40 billion
Source: Motorcycle Dealer News, 1978.
Nearly 44 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:
New Motorcycle Sales 43.8%
Used Motorcycle Sales 10.9%
Accessories 12.9%
Parts 13.9%
Service 12.5%
Other 6.0%
Sou Mó EóF 1e Dealer News, 1978.
2-36
-------
Average annual sales for motorcycle dealers is approximately $360,000.
Approximately 50 percent of the dealers are in the $100,000 - $499,000 sales
range.
The typical dealer has a relatively small profit margin (3 percent before
taxes), and relies heavily on short term financing for his inventory. In-
terest expense becomes critical when sales decrease for dealers with large
inventories. Such dealers are forced to discount their prices, thereby
reducing their profit margin even more. This process is especially crucial to
the smaller dealers who are generally undercapitalized and have a low sales
volume to support their operations.
2.5 Total U.S. Motorcycle Industry Employment
Total U.S. motorcycle industry employment is shown as follows:
Table 2-18
ESTIMATED U.S. MOTORCYCLE INDUSTRY EMPLOYMENT*
INDUSTRY SEGMENT
NUMBER OF EMPLOYEES
SOURCE
New Motorcycle Manufacturers
and Distributors
5,600
1
Afterriiarket Manufacturers
12 ,000**
2
Franchised Dealerships
35,000
2,3
Other Retail Outlets
5,000
4
Miscellaneous
2,000
TOTAL
59,600
Data derived from following sources:
(1) Information from various companies.
(2) 1otorcycle Dealer News.
(3) Motorcycle Industry Council.
(4) Energy and Environmental Analysis, Inc., “Economic Assessment of
viotorcycle Exhaust Emission Regulations”.
* 1975
** 1200 in aftermarket exhaust system manufacturing.
2-37
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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 and strictly competition motorcycles often have no
warranty. To EPA ’s knowledge formal warranties are extended on very few
replacement exhaust systems, although many manufacturers will repair or
replace products that are obviously defective.
2-38
-------
SECTION 3
XJISE LEVEL TEST PR)CEDURES
-------
SECTION 3
NOISE 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 noise measurement procedure for new motorcycles should:
(a) Characterize the noise as perceived at the wayside In terms that relate
to the adverse impact on humans.
(b) Characterize the noise during the most annoying mode(s) of operation
commonly encountered in areas of impact.
(c) Measure noise 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 cart result in variations of measured noise dispro-
portionate to actual variations In vehicle noise.
(5) Free from ambiguous procedural situations requiring determinations
which can affect the measured noise level.
(6) Minimally influenced by factors affecting vehicle performance,
such as atmospheric conditions, rider weight, accessories, etc.
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—1
-------
3.2 Moving Vehicle Test Procedures
SAE J331a (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 mph or 60 percent of maximum rated
RPM 1 (whichever is slower), accelerating at full throttle commencing 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 earli-
er). Second gear is used unless the vehicle travels less than 50’ before
reaching maximum rated RPM, in which case third gear is used. Six measure-
ments on each side are taken, the highest and lowest discarded, and the
reported level is the average of four readings within 2 dB (A-weighted) of
each other on the loudest side.
The full text of the procedure is in Appendix A.
A. Approach at 30 mph or 60% RPM
(the slower).
p25’ 25’ — B. Accelerate in 2nd gear unless 100%
A B C RPM reached before zone C, in
which case use 3rd gear.
C. Close throttle at 100% RPM or at
Microphone end of zone C (the earlier).
Critique:
(a) The highest noise level achieved during a given test occurs at dif-
ferent distances from the microphone for different motorcycles. This means
that for some motorcycles the highest noise 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—li. 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 noise level generated is at a point where the vehicle is furthest
from the microphone. Data on percent RPM attained are also in Appendix C,
Table C—li.
1 As used fn this dociiment, “maximum rated RPM” means the enginispeid
at which “peak brake power” (as defined in SAE J245) is achieved. Percent
rpm is in reference to maximum rated RPM as 100%.
3-2
-------
Cc) 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.
Cd) Different size sprockets are available as options on most motorcycles,
and are readily interchanged by the user. The 50 foot minimum distance
Criterion makes the SAE J331a 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
ifl 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
SAE J331itesE
Ce) 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
RPM 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.
(i ) This test procedure has the advantage of being independent of tachometer
dynamic characteristics for larger motorcycles (approximately 400—500 cc).
CHP Variation of the SAE J331a (Moving vehicle acceleration test)
The California Highway Patrol (CHP) adopted the SAE J331a method.for
type approval with two variations:
(a) if maximum rated RPM is reached before 30 mph, or If a 50 foot accelera-
t1 distance is not attained, the next higher gear Is to be used. (Other
Stipulations of SAE J331a 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 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 SAE J331a 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 in Appendix A.
3—3
-------
Critique:
(a) Variation “a”, above, will primarily affect the smaller motorcycles,
obviates certain test operation difficulties that may result in over-reving,
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 SAE J331a procedure critique
remain in the CHP variation of SAE J331a.
SAE J986a (Moving vehicle acceleration test)
The SAE J986a procedure, although designed for passenger cars and light
trucks, is prescribed in Canada for the testing of motorcycles.
Major differences, referred to SAE J331a, 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.
Critique:
(a) The speed and gear selection stipulations •are not suited to some motor-
cycles.
(b) The gear selection stipulation will result in full acceleration in
1st gear for the larger motorcycles, with possible hazard to the operator.
SAE J47 (Moving vehicle acceleration test)
The SAE J47 procedure was designed to measure the maximum noise potential
of the vehicle. It differs from the SAE •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 maximum rated RPM at a point 25
feet past the microphone.
(b) The gear employed is the lowest gear that does not result in an accelera-
ting distance of less than 50 feet (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....”
3-4
-------
(c) Approach to the acceleration point is made at 60 percent of maximum
rated RPM in all cases.
The reporting method is the same as SAE tJ331a. The full text Is in
Appendix A.
A. Approach at 60% RPM.
3. Accelerate in lowest gear such that
BC is not less than 50’. If this
variable 25’ results in unsafe condition, use
________________ I next higher gear. By trial, point
A B C B is selected such that maximum
50’ rated RPM is reached at point C.
Microphone C. Close throttle at end point C, 25’
past microphone point.
Critique:
(a) The SAE 347 test provides a more consistent measure of maximum noise
level, since all vehicles reach maximum rated RPM at the same point in
relation to the microphone.
(b) Since the above condition does not prevail in the SAE J331a test, corre-
lation between the two procedures cannot be expected, although maximum
differences by motorcycle category may be developed.
(c) As with SAE 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 SAE 347 test the particular gear used
is of secondary importance, since in this test all motorcycles reach maxi-
mum rated 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 (F-76 procedure description) .
Cd) Since in the SAE 347 test gear selection is of only secondary signifi-
cance in relation to measured levels, the matter of sprocket options
(discussed in critique of SAE J33 a) is also not critical.
(e) The safety aspects of the SAE 347 testing procedure are such as to
require a skilled rider familiar with the behavior of the particular motor-
cycle, and exercise of care in its operation.
(f) The procedure is less sensitive to factors affecting vehicle performance
than is the SAE 3331a.
(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.
3-5
-------
The noise control regulations of Italy incorporate a noise test procedure
which in essence is the SAE 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 dynamometer.
ISO/R-362 (Moving vehicle acceleration test)
The International Standards Organization, (ISO) Recoinmer)dation R-362,
Measureinent of Noise Em1t ed 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 incorporated
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 Convilssion 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 percent rpm for peak power or 50
kin/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 in 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 of each other are required on each side of the
vehicles, and the highest value reported.
Full text of the procedure is In Appendix A.
2. App oved does not necessariTy mean adopftóiETiito the regu1 T i 6f
that country.
3-6
-------
A. Approach at 75% rpm or 50 km/h,
whichever is slower.
lOm lOm B. Accelerate in 2nd gear for vehicles
having up to four speeds, 3rd gear
A C for vehicles having five or more
Microphone speeds.
C. Close throttle.
Critique:
(a) The test is simple, and subjective determination of proper gear selec-
tion has been eliminated.
(b) A technical advantage is that acceleration termination is based on
vehicle position, not RPM, thus eliminating errors in closing RPI 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 noise level will be measured on some motorcycles, not
on others.
(e) The problem associated with sprocket options, as discussed in critique of
the StE J331a 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 ISO/R-362 procedure, various countries have adopted or
proposed modifications to the basic procedure. These are discussed below.
ISO/R-362 Variations (Moving vehicle acceleration tests)
“Modified Method”, Appendix A2 to ISO/R—362—1964:
in this variation, the gear is selected which most closely results
in a vehicle speed of 50 km/h at 75 percent RPM, and approach Is made at 75
percent RPM. It is further stipulated that if the vehicle has more than three
speeds, first gear shall not be used.
“ISO/R-362 Proposed Amendment”, 1974:
In this variation, approach is at 75 percent RPM or 50 km/h (whichever
is slower), except that if the speed corresponding to 50 percent RPM is less
3—7
-------
than 50 km/h, then entry shall be at the speed corresponding to 50 percent
RPM. 2nd gear is to be used, unless 100 percent RPM is reached before the end
of the acceleration zone, in which case 3rd gear Is to be used.
JASO Modification of ISO/R-.362 :
This variation of the ISO/R-362 procedure has been incorporated into the
regulations of Japan and Belgium. Modifications to the basic ISO/R—362 are in
gear selection and approach speed:
JASO* ISO/R—362
Gear
Selection
2nd gear:
2, 3—speed gear box
2nd gear:
2, 3, 4-speed gear
box
3rd gear:
4-speed gear box
3rd gear:
over 4-speed gear
box
4th gear:
over 4-speed gear box
Approach
Speed
25 km/h: under 50 cc
40 km/h: 50-249 cc
50 km/h: 250 cc & over
(or 75% RPM)
50 km/h
(or 75% RPM)
‘Second Draft Proposal”, Revision of IS0/R—362, May, 1975:
Major revisions, referred to the ISO/R-362 procedure are:
(a) Vehicles having 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 measurements.
(b) The procedure for testing vehicles with automatic transmissions is
revised and expanded.
Japanese Acoustical Standards Organization
3-8
-------
Critique:
(a) The numerous variations of ISO/R-362, 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 stuciy 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/R-362 procedure (JASO, iSO, ISO
Proposed Amendment). These variations, differing only in approach speed
and gear selection, yielded measured noise level variations up to 12 dB,
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 noise level. (The Japanese Investigators determined that the JASO
modification of the ISO/R-362 procedure yielded the best correspondence
with average noise due to average acceleration, as related to Japanese
urban traffic situations.)
F-76 (Moving vehicle acceleration test)
While all of the above test procedures are considered to be candidates
for use In the final EPA regulations, all of these procedures were found to
have shortcomings as a methodology for the Federal regulations. These short-
comings fall in one or more of the following areas:
(a) Safety; hazard In testing (SAE J47)
(b) Antlgulty; measured level dependent on gear selection involving a sub-
jective determination (SAE J331a)
(c) Sprocket variables; measured level dependent on sprocket ratio which is
readily changeable; change in measured level disproportionate to change in
vehicle noise (SAE J331a, ISO/R—362)
(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 (SAE J33la, ISO/R-362)
(e) Performance variables: atmospheric conditions, rider weight, or acces-
sories affecting vehicle closing RPM and/or position (SAE J331a, 1S3/R-362).
Representatives of the U.S. Suzuki Motor Corporation and the California
Highway Patrol, submitted preliminary drafts of test procedures designed to
eliminate the above objections. These procedures, together with other
procedures, were evaluated and refined. The resulting procedure has been
designated F-76, and consists of the following:
. See page -4(T.
3—9
-------
Approach is made at 50 percent of maximum rated RPM. The throttle is
smoothly and fully opened, commencing at a point such that 75 percent of
maximum rated 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 accelerating 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 in Appendix A.
A. Approach at 50% RPM.
B. Accelerate in 2nd gear from point
B, selected such that 75% RPM is
1 25’ reached at point C. If BC is less
var ab e _________ than 25’, use next higher gear.
A B C If speed at C is more than 62 mph,
50’ use 1st gear.
Microphone C. Close throttle.
Critique:
(a) Safety. The procedure does not require rapid opening of the throttle;
mandatory requirement is that wide open throttle at 75 percent RPM be attained
25 feet past the microphone. No instances have been encountered in EPA’s
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. Although the
procedure does not require such. 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 that were conducted 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 SAE J47, F—76), are relatively insensi-
tive to gear selection (Table 3-1).
(c) Sprocket variables. The relative insensitivity to gear selection
in the F-76 test shows that a change in sprocket ratio will have little
effect on measured noise levels.
3-10
-------
Table 3-1
EFFECT OF GEAR SELECTION ON MEASURED NOISE LEVELS
SAE
SAE
Bike No. Category Dispi. J331a F
76 J47
101 S 356 —0.2
—1.3
103 SX 123
109 X 248 —5.5
119 S 398 —1.7
126 S 184 -0.3
123 SX 249
127 S 738
130 98 —3.2
131 S 371
132 S 543
134 S 246
135 SX 173 —1 .6
146 X 246
*151 S 949 —1 .7
153 X 248
155 SX 98 -0.9
*160 S 736 -3.7
161 SX 247 —1.1
*166 SX 72 -2.6
173 SX 397 —1.7
181 SX 183 —3.3
191 SX -1.3
197 SX 242 -4.0
3—11
-------
(d) Position variables. In the F-76 test, the noise level, at the sped-
f led power and RPM conditions, Is always measured at the same distance from
the vehicle.
(e) Performance variables. As with the other test procedures, the measured
level in the F-76 procedure will be affected by factors which affect sound
power (such as relative air density); correction factors could be applied for
this. In contrast with the SAE J331a procedure, however, the F-76 measured
level is not affected by RPM/distance relationships associated with variations
in power output.
(f) Methodology substitution. Since the F-76 test is conducted under
controlled conditions of power, RPM, and measurement distance, it can be
deduced that the means used to load the engine are relatively unimportant.
For example, the same result should be obtained on a grade, or on a suitable
dynammeter, as long as the prescribed end-conditions are attained. (The
Italian procedure, which is similar to the SAE J47, permits these substitu-
tions in lieu of the prescribed acceleration test). in contrast, procedures
such as the SAE J331a or the ISO/R-362 offer no possibility of such substitu-
tions as equivalents.
(g) Tachometers. Tachometer lag time can have an inportant effect on the
noise levels measured by F-76. Slow-responding tachometers will indicate
engine speeds higher than those specified in the procedure 25 feet past the
microphone point. These higher engine speeds will result in erroneously high
noise level measurements.
While it Is possible to derive a statistical transfer function between
F-76 and SAE J331a (as has been done in section 4) It is not possible to
predict, for a particular motorcycle, the F—76 level based on the SAE J331a
level using this transfer function. The reasons for this are fundamental.
For the smaller motorcycles, the SAE J331a level is dependent of where in the
end-zone the vehicle reaches 100 percent RPM. If it reaches 100 percent RPM
near the start of the end—zone, the F-76 level (75 percent 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 SAE J331a closing RPM. If the closing RPM Is at a near 100 percent, the
two levels will be near equal; if the closing RPM is well below 100 percent,
the F-76 level will be higher. By making use of these factors, toqether with
vehicle performance data, it would be possible to estimate F-76 levels for
a particular motorcycle, based on the SAE J331a level.
For the above reasons, no close correlation should be expected between
the F-76 levels and SAE J331a levels. It was considered of interest, neverthe-
less, to examine the degree of correlation, which is shown in Figures 3-1 and
3-2. The relatively good correlation in the case of the off-road motorcycles
is no doubt attributable to the fact that most of these are small displace-
ment, low-geared machines, and therefore reach the acceleration end point near
the microphone in both test procedures.
3-12
-------
+ 2 STROKE
4 ST KE
V 17.37 + c .793 X
r = 0.73
= 2.9
I I I I I I I
• I
J331a NOISE LEVEL, dB
FIGURE 3 I CORRELATION BEIWLEN F-76 AND J-
STREET AND COMBINATION sTREET/orF—RoA:
1975—1976 YEAR OF MOTORCYCLE MANUFACTURE
I 10
100
90.
801
70
60
D
+
S
yx
+
+
60
70
I 00
I 10
3—13
-------
I 2,93 + 0.943 X
r= 0.97
1 .72
90
NOISE LEVEL, dB
a
I-
100 110
FIGURE 3—2 CORRELATION BETWEEN F—76
OFF-ROAD (ONLY)
1975-1976 YEAR OF MOTORCYCLE
and J —33Ia TESTS,
MANUFACTURE
+ 2 STROKE
rl A 1flAL’
.)Ir’..ur
+
110
100•
8O
70
a
-J
Lu
Lu
-J
Lu
Li
+
+
S=
yx
“U
60
I I
70 80
J331a
3—14
-------
Note: In the initial drafts of this procedure, a 50 ft. minimum acceler-
ation 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 percent RPM even in the highest gear; others (350 cc class
off-road bikes) would not pull properly from 50 percent 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 refer to Table
3-1) to 25 feet. The 25 ft. minimum distance stipulation presented no prob-
lems in the testing of any of the motorcycles.
F-76a (Moving vehicle acceleration test)
In examining the noise emi 4 ssion data base (Section 4), in terms of
SAE 4 1331a levels (Figure 4—1) , and in terms of F-76 levels (Figure
4-3) , the SAE J331a method yields a regression line nearly flat (noise
level independent of displacement), whereas the F—76 method shows a definite
upward slope of the regression line with engine displacement.
The reason for this is, of course, that in the SAE 3331a test the larger
motorcycles pass through the measurement zone without reachin9 maximum
rated power RPM, whereas in the F-76 test all vehicles are measured at
75 percent RPM. The ISO/R—362 test is similar to the SAE J331a test and
recognizes the fact that both in constant speed and in accelerating modes the
smaller machines will usually be operated closer to their maxiiiiurn potential
than will the larger machines. This is not only because of available horse-
power, but also, in the small machines the torque curve is characteristically
steep, favoring operation at high RPM. In the large street machines the
torque curve is relatively flat, resulting in acceptable performance at lower
rpm’ S.
To take this factor into account, a variation of the F-76 method,
designated F-76a, was investigated. The F-76a procedure differs from the F-76,
in that instead of testing all vehicles at 75 percent RP l, the test RMP is a
function of displacement. The RPM/displacement relationship follows:
y = 90% at (0-100 cc) where y is % RPM
y 95% .05x at (100-700 cc) x is displacement, cc
y = 60% at (70W- cc)
This relationship, shown graphically in Figure 3—3, yields a test
RPM of 90 percent at 100 cc, reducing to 60 percent at 700 cc. Above 700 cc
the closing RPM remains constant at 60 percent. Entering RPM is 50 percent or
20 percentage points below closing RPM, whichever is lower.
The basis of the F-76a RPM/displacement relationship is the data col-
lected in the course of EPA’s test program where a number of motorcycles
were tested at more than one closing RPM. These data appear in Appendix C
and in Tables C-li and C-12, and are surm arized in Table 3-2 and Figure 3-4
in this Section.
4 Figures pertaining to the iToi se emi s Ton datãbi Fi esentèTT i
Section 4.
3-15
-------
0 -
tjJ
I-
I-
0 200 400 600 800 1000
DISPLACEMENT - cc
FIGURE 3-3 CLOSING RPM FOR F76a MOVING VEHICLE ACCELERATION TEST
1200
-------
TABLE 3-2. COMPARISON OF F-76a AND SAEJ331a NOISE LEVELS
Displacement Mean Noise Level, dB Standard Deviation Nun er of
Range SAE SAE Vehicles
cc F76a — J331a F76a J331a in Sample
100 — 125 80.8 80.9 2.57 2.62 10
175 - 250 80.8 80.9 1.73 2.34 8
350 — 400 82.5 81.1 1.77 3.55 6
550 - 750 82.3 81.9 1.38 0.71 6
900 - 1200 82.6* 80.6 1.91 3.58 4
The vehicles in this sample are unmedified, 1975 - 1976 year of manufac-
turer, street and contination street/off-road motorcycles. The F—76a levels
have been derived by interpolation or extrapolation of noise levels measured
at RPM other than the F-76a RPM. The SAE J331a levels are directly measured
data.
*Thjs ma1l sample of 4 included two vehicles whose F—76 level was con-
siderably higher than the average of other vehicles in this category.
-------
Displacement (c.c.)
FIGURE 3—4
COMPARISON OF F76 AND F-76a NOISE LEVELS
3—18
.v
C)
C)
-J
C)
•1
0
r
U.,
r
0 )
C)
-J
C)
0
z
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>
-J
0)
0
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C.)
.,-
C)
>
0)
-J
C)
0
0
LL
+5
—5
+5
—5
.-
—
• •
—
.-
-.
.
—
‘
—-
—
S
..__.•
.
..—
I
•
.
—
.—
p.
.
—.--— ..— S
—
.
S
•
p
S
—.-
•
. •
• S
S
F—76 noise levels for
motorcyci es represented
In Table C-12
200 500
700 850
.
S
.
S
S
.
•
S
4
•
S
p4
U
— I
—
S
S
.
S
S
2•
.
F-76a Noise levels from
linear interpolation and
extrapolation of data in
Table C-l2
1200
0 200 500 700 850
1200
-------
Figure 4_55 shows the difference between F—76 and SAE J331a levels
plotted against displacement, with the upward sloping regression line showing
that statistically the F-76 level is higher than the SAE J331a level for
large motorcycles, lower for small motorcycles. Table 3-2, shows that while
a larger statistical sample of F-76a test data is desirable, the data indicate
that if F-76a data were substituted for F-76 data, the regression line would
not only be independent of displacement, but would also be approximately equal
to the SAE J331a levels on a statistical basis.
A curve of noise level versus percent 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 for the large motorcycles. In the F-76 test, speeds up
to 55 mph were encountered. This would reduce be about 45 mph in the F-76a
test. Manufacturer test data show tire noise of 66 dB at 45 mph on a 750 cc
motorcycle, which indicates that tire noise would not be a significant contri-
butor to total vehicle noise in the F—76a test.
Text of the F-16a procedure is in Appendix A.
R-60 (Moving vehicle acceleration test)
With the same rationale basic to the F—76a test, a staff member of
AMF Harley-Davidson submitted (prior to development of the F-76a test) a
moving vehicle acceleration test procedure designated R-60. The R-60 test is
similar to the F-76a except that the closing RPM is the RPM corresponding to
60 mph in the highest gear (instead of 75 percent RPM for all vehicles).
Entering RPM is 75 percent 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 percent RPM before 60 mph shall be tested at
100 percent RPM.
(b) Similar vehicles, differing only in gearing, could be tested at substan-
tially different RPMS5 yielding substantially different measured levels.
(c) Changing sprockets would result in testing at different RPM’s, with
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 percent RPM, a rather low
test RPM.
5. Figures pertaining to fhëThöise emissio d ii ”1Fë ted f
Section 4.
3—19
-------
90
88
F76 LEVEL
The 75% rpm data point was
obtained using the F76 test
procedure. The test
used to obtain the other data
points was the same except
V
-a
for closing rpm, which was
-J
varied as shown on the plot
U i
w
/6a LEVEL
Ui
1 ) _______ ________
0
82
80 I I
50 60 70 90 100
PERCENT RPM
FIGURE 3-5 EXAMPLE OF NOISE LEVEL AS FUNCTION
OF PERCENT RPM (HARLEY XLH-1000)
3—20
-------
(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 representa-
tive of comon operational conditions for vehicles under-lOU cc. It yields
levels usually close to the SAE J331a levels, and can be expected to yield
levels close to the F-76a test.
Full text of the procedure is in Appendix A.
Problem Areas: Moving Vehicle Test Procedures
(1) Automatic Transmissions
Automatic transmissions are coming into use for both street and off-road
motorcycles, large and small. The following motorcycles with automatic
transmissions were tested:
Street
Moto Guzzi V1000 Converter
Honda CB75OA
Honda NC—50
0ff-Road
Rokon 340 RT
Husqvarna 360 Automatic
Combination Street/Off-Road
Yamaha Chappy (,ninibike)
Mopeds
NTV Model ERB
Kreidler MP3
Vespa Ciao
Motobecane Mobyl ette
Velosolex 4600
Peugeot 1O3LVS.1J3
3-21
-------
Difficulty was encountered in testing the motorcycles with automatic
transmissions. The Moto Guzzi V1000 and the Honda C3750a incorporate a high
and low—range selection; low range produces significantly higher levels for
the SAE J33la test. High-range use for the F-76 test results in excessive
speed. For the F-77 test, however, high—range can cause the engine to
over-rev unless it is specified.
The Rokon 340RT and the Husqvarna 360 Automatic also presented testing
problems. The Rokon 340RT incorporates a variable ratio belt drive; the
driving member is acted upon by centrifugal forces, the driven member is
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 SAE J331a test procedure, does not provide forthe
testing of vehicles with automatic transmissions. (owever, if the gear
stipulation is ignored, a meaningful SAE J331a 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 percent
RPM; with some practice, vehicle speed can be smoothly increased such that 75
percent RPM at full throttle is attained at the required end point, with good
consistency. As discussed in Section 3.2, vehicles which reach 100 percent
RPM near the end of the end-zone in the SAE J331a test exhibit near equal
SAE J331a 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 SAE J331a
test cannot be run, because 100 percent RPM is reached well before the start
of the end-zone, and no rational criteria exists for regulating the throttle
other than wide open. No technique has been developed which would achieve
full throttle at 75 percent RPM at the 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 F-77 testing of two motorcycles with displacements less
than 100 cc and six mopeds, no problems occurred with vehicles with automatic
transmi ssions.
(2) Tachometers
A major problem encountered throughout EPA’s test program was in ob-
taining 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 TAC 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 motorcycles. In some
cases the testing of a motorcycle was abandoned because of inability to obtain
proper functioning of the tachometer.
3-22
-------
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 and matching the two signals 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 hrottle 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 tachometer incorporating a
“max. hold” mode (Emission Control Instruments, Precision Tachometer). In
that study, when the rider performed SAE J47 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 SAE J47 tests were repeated with the closing RPM at the proper value
estabif shed by the electronic tach, measured levels ranged from zero to 2 dB
lower.
Test methodologies such as the SAE J331a 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 dyna ioineter method is free of these problems, since
the tachometer can be incorporated into the dynamoi ,ieter, and measuring
conditions are steady-state.
3.3 Stationary Vehicle Test Procedures
F-50 (Stationary vehicle test)
The F-SO procedure is patterned after the ISO proposed draft, “Method
of Control of t Joise Emitted by Stationary Motor Vehicles,” July 1974. The
test consists of running the engine up to 50 percent RPM, unloaded, and
measuring noise at a distance of 0.5 ni from the exhaust outlet, on a line
displaced 45° from the exhaust axis. The complete text of this procedure
and the ISO draft are 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 SAE J331a
and F-76 levels in Figure 3-6 thru 3—9. The correlation is not sufficien-
tly good as to permit the moving vehicle acceleration noise for a particular
vehicle to be predicted from the stationary level. Major reasons for this
épi e 3-
3-23
-------
+ 2 STROKE
: 4 STROKE
+
-I. ;
0
0
I I -
+
0
y 28.79 + O.764
syx 3.73
60 70 80 90 100
Ho
J331a NOISE LEVEL, dB
FIGURE 3—6 CORRELATION BETWEEN F—50 and J—331a TESTS,
1969—1976 MODEL STREET AND COMBINATION STREET/OFF—ROAD MOTORCYCLES
00
C
1 2O
lic
100
90
80
7n
-J
uJ
U i
V)
‘ -—4
L
LL
+
+
r 0.64
3—24
-------
+
-J
Lu
LU
-J
Lu
( ii
CD
CD
Lu
+ 2 STROKE
4 STROKE
+
+
0
+
+
120
1 10.
100.
90
80
70.
60
+ +
+
++
+
+
+4
0+
+
+ 1 13
y = 24.88 + O.78x
r = 0.73
4.85
I I I I I I I
8b 90
J331a NOISE LEVEL, dB
iob
110
FIGURE 3—7 CORRELATION BETWEEN F—50 and J-33 TESTS,
1969—1976 MODEL OFF-ROAD (ONLY) MOTOR”YCLES
3—2s
-------
+ 2 STROKE
D A STROKE
+
F-If 1 N1C E , cIB
FIGURE 3 - 8 CORRELAT iON BETWEEN F-SO AND F — l B TESTS,
1969-1976 MODEL STREET A W COMR1NPJION STREET/OFF—ROAD MOTORCYCLES
120
110
100
go
cc
-o
-4
1 - 4
w
- 4
U ,
p — i
C
C
U ; )
U -
+
+
+
+
+
C
S
80
C
0
0+ Y 30.85 ÷ 0.726x
syx 3.49
+
r= 0.69
70
70
80
90
100
110
3—2€
-------
+ 2 STROKE
C
+
I I I I I I I
60 70 90 io0
1-76 NOISE LEVEL, dB
FIGURE 3-9 CORRELAT 1 ON BETWEEN 1-50 AND F—76 TESIS,
1967 - 1976 MODE. OFF-ROAD (ONLY) MOT3RCYCLES
aD
m
-J
w
-J
h i
Cjl
0
4 STROKE
+
+
20
IJO
100
90
80
70
+
+
+
+
0+
y = 19.82 + 0.855x
r = 0,77
S =4.63
yx
3—27
-------
are that the engine is not under load, and thus exhaust noise is not represen-
tative 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 noving
vehicle noise 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) noise level was
known and labeled on the machine.
A further alternative to the F-SO test, for use by the exhaust system
manufacturer, could be the dyno-sitnulation of the moving vehicle test, as
discussed later in this section.
iotorcycle Industry Council (MIC) Proposed Field Test Procedure
for Noise Levels of Competition Motorcycles, Rev. 1-30-76
This procedure, the full text of which appears in Appendix A, is similar
to the F—SO procedure, differing mainly in features which make it more con-
venient for application in competitive events. Test RPM is 50 percent red—
line, alternatively 60 percent maximum rated RPM, or alternatively calculated
from a formula as a function of stroke di t1ension.
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-76Uyno-Simulation (simulated moving vehicle acceleration test)
A cursory investigation of the feasibility of simulating moving vehi-
cle acceleration tests on a dynaiaoineter was conducted, using one notorcycle
(honda C D 750) and a Pabatco Dyno (made by Weda Instruments). This dynarnome—
ter is one of the lowest priced portable units connercially available, not
specifically designed for noise testing, and not incorporating any quieting
provisions (Figure 3-12). The motorcycle was successively fitted with seven-
teen different exhaust systems, which resulted in F-76 levels ranging iron
82 to 98 dB. For the dyno-simulated F-76 test, the dynainometer was set up
at the test site at the F-76 test track end point, with the microphone
positioned as it would be for the actual F—76 test noving vehicle test.
Noise level as measured at 75 percent RPM at full throttle was established, a
procedure taking about 15 seconds. Figure 3—13 presents the correlation of
results fro’i 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 syste’is were on the right side only; this because the dyna’4ouneter
confi urdtion precluded taking readings on the right side.
3-28
-------
30 T
I 0
+ 2 STM E
0
o 4 STROKE o
0
20 DO C
D OD
0 0
0
-J 15
I 0 0 0
I 0
C
DOD 0 0
10• I DO
I ODWOD
0 ifiDO 0
D D 00 0
00 0 +
U, 5 DDD 0
000W DO
o oo o
L)
00000
0.
DD
C
—5. 1 I I I I
—5 0 5 10 15 20 25 30
CHANGE IN J331a NOiSE LEVEL, dB
FIGURE 3—10 CORRELATION BETWEEN CHANGE IN F—50 NOISE LEVEL
COMPARED TO CHANGE IN J331a NOISE LEVEL, AFTERMARKET AND MODIFIED
CONFIGURATIONS REFERRED TO ORIGINAL MANUFACTURE
3—29
-------
30—
I I + 2STROKE
I o 4STROKE 0
0
00
I 0
20 I 0 00
-J I 00 0
u - i 0
0 0
u - i
-J 0
u-i 15
0 0 0
C) I 0
0 0
C) I 0 0 0
10 00 0 0
ID 00 DO 0
0 +00 0
I 0 00
1000 +
900
= I o+oo Do
4 othoo o
c - i
O DD
0
--
DiD CD
OH 0
C
I I
.5 Q 5 10 15 20 25 30
CHANGE IN F-76 NOISE LEVEL, dB
FIGURE 3-1] CORRELATION BETWEEN CHANGE IN F-SO NOISE LEVEL
COMPARED TO CHANGE IN F—76 NOISE LEVEL, AFTERMARKET AND
MODIFIED CONFIGURATIONS REFERRED TO ORIGINAL MANUFACTURE
3—30
-------
.1 ; ) .
-
k .
C l ,
(A)
-A
FIGURE 3-12 PABATCO DYNAMOMETER
-------
+,
+4
+
y ‘ l. 0 72x -
r 0.94
5 ‘2.21
yx
I I I I I I
90 95
F-76 NOISE LEVEL,dB
100
FIGURE 3-13 CORRELATION BETWEEN DYNO—SYMULATED F-76,
AND I\CTtJAL F—76 MOVING VEHICLE TEST
105
100
95,
90
85
-J
I-IJ
-J
L J
v)
‘,O
r
U-
LU
-J
>-
+
++
5.474
80
80
85
3-32
-------
Potential advantages of the dynarnoineter 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
determi ‘ ation
- rei3oval of wind, weather, micro-meteorological variables
— minimization of site variables
As discussed in Section 3.2, dyno—siniulation of the SAE J331a or ISu/ -362
test procedures is not feasible.
3.4 Measurement Distance Substitution
All of the noise e iission data presented in this report were measured at
a 50—foot distance (except the F—50 data, which were measured at 3.5 m), as
delineated in the respective procedures. An investigation was made, h ever,
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 acceleration test (as opposed to a
Constant speed test).
The reason for the lack of correspondence bet ieen 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 fro 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 chan i fly
RP1 .
3-33
-------
TABLE 3-3 RELATIONSHIP BETWEEN 25 FT. AND 50 FT. NOISE LEVEL MEASUREMENTS
BIKE
NO.
DISPI.
CC
ENGINE
TYPE*
DIFFFP NCE BETWEEN 25 FT AHD 50 FT
READINGS, dB
J331a F76 F77 55 MPH
101
356
4 5
5.6
6.2
TO2
72
4 5
3.1
4.3
To3
104
123
999
2 S
4 S
5.0
5.8
5.4
.
.
105
736
4 S
7.6
—
1O9
248
4 S
5.0
.
1 0
124
4 S
1.6
1.9
1 1
171
2 5
4.1
1 2
99
4 S
2.1
248
45
a.a
—
114
99
2 S
3.5
4.1
1 5
99
2 S
4.6
4.8
1 7
— 99
2 S
3.1
3.8
1 8
174 —
2 S
5.0
119
400
2 S
4.0
6.0
—
12
746
4 S
3.5
—
140
828
4 S
4.5
5.4
141
49
2 S
50
142
744
4 S
6.3
7.2
143
246 -
25
6.5
6.9
145
981
4 5
5.1
5.3
146
246
2 S
3,6
5.9
14€ .___
246
25
5.3
i i__
151
949
949
4 S
4S
7.3
6.7
7.3
152
336
- 98
2 S
2 S
5.5
4. 6
4. 1
•
—
98
2S
4.3
156
72
2 S
3.5
4.6
5.3
57
49
25
6.5
58
898
4 S
5.8
8.1
,
7 .0
159
750
4 S
5.4
6.1 —
16o
736
4 S
4.4
—
160
736
4 S
5.2
160
:i i____
736
247
4
2 S
69
4J
—
U_
247
124
2 S
2 S
..9
6.8
5.8
63 —
903 —
4 S
7.1
6.6_
6.6
* 2S denotes 2 stroke
4S denotes 4 stroke
3-34
-------
10
9
a
8
0
U
7. + + u c i
+ +
0 ri I
6 + 1 0 0
U,
+0 0
+ +
5’ + ++
Lf)
4 o
£11
+ + +
LU
++ + 0
. 0+
LU C l
V.)
2 STROKE +
2 4 STROKE 0
U
0 I I I
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 3—14 DIFFERENCE BETWEEN 50 FT. AND 25 FT. MEASURED NOISE LEVELS
DURING ACCELERATION (J331a AND F-76) TESTS
-------
10
9.
8
7. 0
00
C
5.. 0
+
Li.J
3
2 2 STROKE
4 STROVSE iii
1
0 I I I
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
FIGURE 3-15 DIFFERENCE BETWEEN 50 FT. AND 25 FT. MEASURED NOISE LEVELS
DURING CONSTANT SPEED (35 (‘PH AND 55 ( ‘PH) TESTS
-------
REFERENCES
1. Motorcycle Noise Studies , report published by the Japan Automobile
Manufacturers Association, Inc., 1otorcycle loise Control Comittee,
July, 1975.
2. Hornett, H. and Williamson, I. 11., Evaluation of Stationary and Moving
Motorcycle Noise Test Methods for Use in Proposed Regulations , McL)onnell
Douglas Astronautics Company report prepared for €he Motorcycle Industry
Council, Inc.
3-. 37
-------
SECTION 4
NOISE LEVEL DATA BASE
-------
SECTION 4
N0ISE LEVEL DATA BASE
4.1 Content and Format of the Data Base
The basic motorcycle noise level data base used for this regulation
is presented in Appendix C. Noise data for the following are included:
(a) 159 new 1976 model year iotorcycles (manufactured in 1975 and 1976);
(b) 60 motorcycles (manufactured in 1974) in stock configuration;
(c) 257 in—service motorcycles in stock configuration, manufactured 1969-
1973 (includes the data developed in the MIC motorcycle testing program);
(d) 43 in-service modified motorcycles, manufactured 1969-1976;
(e) 107 motorcycles with new afterrnarket exhaust systems.
Motorcycles in group “a” above provide the best noise level baseline
for assessing cost and economic impact of adoption of standards more stringent
than 83 dB (for Street i otorcycles) 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 the off—road category, since regulation of noise emissions
from those vehicles has been very limited in most states.
iotorcycles in group “a” through “d” provide a baseline for assessing
environmental improvement that can result from regulation of the new vehicle,
the after iiarket product, and user modifications.
Motorcycle afterinarket data, group “e”, show the degree to which curren-
tly offered-for-sale aftermarket exhaust systems affect new vehicle noise
emi ssions.
The total sample of vehicles, groups “a” through “e” above, were employed
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
BMW R9OS
BMW R60/6
Bultaco 250 Alpina
Bul taco Frontera
Bultaco 350 Sperpa T
Bulotaco Matador MK9
Bulotaco 250 Pursang
Can Am 125 TNT
Can Am 250 TNT
Can AM 250 MX1
Carabela 125 Marquesa MX
Carabela 250 Centauro
Ducati DM75OS
Garelli Moped
Harley FXE—1200
Harley FLH—1200
Harley SS125
Harley SS175
Harley SS250
Harley SX 125
Harley SX 175
Harley SX 250
Harley XLH1000
Hodaka Road Toad
Hodaka 250
Honda CB 400F
Honda CB 500T
Honda CB 750A
Honda CB125S
Honda CB 1255
Honda CB200T
Honda CB35OF
Honda CB 360T
Honda CB 450
Honda CB 550
Honda CB 550F
Honda CB 550T
Honda CB 750
Honda CB 750F
Honda CJ3601
Honda CL360
Honda CL450
Honda CR125M
Honda CT7O
Honda GL1000
Honda MR5O
Honda t4R175
Honda MR12S
Honda TL250
Honda XL7O
Honda XL7OK2
Honda XL100
Honda XL1 25
Honda XL1 75
Honda XL2SO
Honda XL3 50
Honda XR— 75
Honda ZSOA
Honda All terrain
Honda CT9 0
Honda NC5O
Husqvarfla 360
Husqvarfla 360
Indian Mu 75
Kawasaki 900Z].
Kawasaki KD8O
Kawasaki KE125
Kawasaki KE175
Kawasaki KH 100
Kawasaki KH 250
Kawasaki KH 400
Kawasaki KM lOOA
Kawasaki KT 250
Kawasaki KV 75
Kawasaki KY 100
Kawasaki KZ 400
Kawasaki KZ 400D
Kawasaki KZ 400s
Kawasaki KZ 750
Kawasaki KZ 900
Kawasaki KZ 9 00LTD
Kreidler MP3
Laverda 750SF
Larerda l000Three
1ontesa 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 Cormiiando
NVT ERB Moped
Ossa Desert Phantom 250
Ossa 250 Pioneer
Ossa 250 Plonker
Peugeot 103 LVS V3
Rokon RI —340 11
Suzuki G1185
Suzuki GT380
Suzuki G1500
Suzuki GT550
Suzuki G1750
Suzuki RE—5 Rotary
Suzuki RM125
Suzuki RV9O
Suzuki 1M75
Suzuki TS100
Suzuki TS185
Suzuki TS400A
Suzuki TS400S
Velosolex 4600 Moped
Vespa Ciao Moped
Yamaha Chappy
Yamaha DT100C
Yamaha DT175
Yamaha 0T175C
Yamaha DT250
Yamaha D1250C
Yamaha DI400C
Yamaha DT65OC
Yamaha MX125
Yamaha RD125B
Yamaha RD200B
Yamaha RD200C
Yamaha RD250
Yamaha RD350
Yamaha RD400C
Yamaha RS100B
Yamaha TX750
Yamaha TY8O
Yamaha XS36OC
Yamaha XS65OB
Yamaha XS65OC
Yamaha XTSOOC
Yamaha X1500
Yamaha YZ125C
Automatic
WRX
4-2
-------
The vehicle population tested encompassed street, off—road, and combina-
tion use motorcycles; 50 to 1200 cc displacement; 2-stroke, 4-stroke and
rotary engines; 1, 2, 3, 4, and 6 cylinders; manual gear shift, automatic
clutch, hydraulic torque converter, and centrifugal torque converter trans-
missions; a few mopeds were also included.
Test methodologies employed in acquiring the data base include the
SAE J331a, F-76, and R-60 acceleration tests; the F-77 full—speed/full—throt-
tle test for under-lOU cc bikes; the F—SO 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. Noise levels at 35 mph and 55 mph,
constant speed pass—by, have also been obtained on a representative group of
vehicles.
The noise level data base of new motorcycles manufactured 1975—1976 is
presented primarily in terms of SAE J331a, 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 presentations is as
follows:
(a) SAE J331a 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:SAE J331a, by displacement category and overall --
Figures 4—S 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 1975-1976 year of manufacture motorcycles, but also
similar data for 1969- 1974 in-service motorcycles, motorcycles with modified
exhaust systems, and data on aftermarket products. The tabular presenta-
tions include:
(a) Noise levels (SAE J331a, F—76, R—60, F—77, F-50, 35 mph, 55 mph) by
displacement and use categories; new motorcycles, year of manufacture 1975 and
1976: Table C—4.
(b) Same data as Table C-4; by manufacturer: Table C-5.
(c) Noise levels (SAE J331a, F—76, F-77, F-50, 35 mph, 55 mph) by displace-
merit and use categories; in—service motorcycles, year of manufacture 1969-
1974, in stock configuration: Table C-6.
4-3
-------
= 780 81.5
a4.44 a2.95
n15 n=1O
81.4
o = 3 .96
\ 2 STROKE f
4 STROKE H
y= 80.55 3 O.00079x
0
0 .9
800 900 lfJOO 1100 1200 1300
0
0
OF F- ROAD
120
1
83.1
a = 4.49
n 23
1
80.6
a = 2.99
100
÷
-J
LU
LU
I .)
-J
90
+
+
+
80
ci
+
U
ci
+
+
70
I3
U
+
I
I
I
I
I
I
9
0
60
B
0
100
200 300 400 500 600 700
LHSPLACEMENT, cc
FIGURE 4-1 J331a NOISE LEVELS, STREET AND COMBINATION STREET 1
- MOTORCYCLES MANUFACTURED 1975-1976
-------
78.8
3.35
5
1÷
1+
I
9L8
a = 10.11
1÷
IF
DISPLACEMENT, cc
FIGURE 4—2 J331a NOISE LEVELS, 0FF—ROAD (ONLY)
MOTORCYCLES MANUFACTURED 1975-1976
x =
0 =
•; •= 92.3
(7 = 3.79
7
88.8
a = 4.96
Ti = 16
-J
U i
LU
-J
LU
C l )
C)
El
+
+
+
y = 82.23 •f O.026x
2 STROKE +
4 STROKE fl
0
L
300
400 500 oo 700
800 900 1000 yj 1200 1300
-------
120
. .= 79.5
o - 2.64
Ti = 10
I /f
DISPLACEMENT, cc
FIGURE 4-3 F-76 NOISE LEVELS, STREET AND COMBINATION STREET/OFF-ROAD
MOTORCYCLES MANUFACTURED 1975-1976
-= 77.0
a 4.22
Ti = 1 1
1
•• = 81.95
a = 4.94
‘1 = 40
1
= 81.9
a = 2.63
Ti =40
• = 85.5
a =. 3.47
= 18
4
-
4 ’
—J
w
u - i
-J
u - i
(I- )
0
IL
+
+
110
100
90
80
70
60
0
+
2 STROKE
4 STROKE
+
-4-
Li
0
+
++
B
U
a
0
9
B°
c i
U
0
ci
c i
y = 75.7 + 0.01 x
100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
-------
. ‘262x
DISPLACEMENT, cc
FIGURE 4—4 F—76 NOISE LEVELS, OFF—ROAD (ONLY)
MOTORCYCLES MANUFACTURED 1975-1976
= 76.4
a = 1.82
n
86.8
a 5.34
= 88.7
a = 10.4
1
ci
‘I
-J
U i
U i
-J
L i i
V)
‘a
r;.
y 79.54 4 0
+
+
U
2 STROKE -
4 STROKE 0
600
700
-------
DISPLACEMENT, cc
2 STF )KE 4
FIGURE 4-5 COMPARISON OF F—76 A [ ) J331a NOISE LEVEL .
STREET AND COMBINATION STREET/OFF-ROAO
MOTORCYCLES MANUFACTURED 7975-1976
to
a
-J
w
-J
= -1.82
a 1.94
= 11
= -1.82
a = 1.89
7) 11
5
= —1.27
a = 1.80
= 22
= 1.21
a = 2.26
11 = 39
--
LU
U,
‘—4
C .,
= 40
a = 2.72
71 = 18
I \
c o
o ci
o ci
0
+
a
0
ci
+
0
+
-J
LU
LU
-J
0
+
0
—5
C
0
c l i i i
LU
U,
L
+
+
+
+
ci
y -2.48 + O.0066x
- 10
I
4 STROKE H
500
900
1000
1100
1200 1300
-------
10
x = -1.5 x = -2.0 = -2.0
a 1.0 a = 1.73 C l = 1.83
ri= 3 n16
9.
LU
i
1’
I ’ I
I I i I I
I I I I
LU i
I I I I
V ) I
I I
I I
I I I
I I I
I I I
I I I I
1 • I
I I I
(V) i + 1
- I I
____ ___ _________ I _____________________ I ____________________
0 I _____________
-w + +1 I
I I
-hr
y = - 2.21 + O.0012x.
+
I I
LU I • - +
-J
I • I
w -5 I 1 2STPOK [ +
I I
c i 4 STPOV.E [ 1
I I I
I I I p
I I , I
N .. I I I
• I I I p
I I I I
I I I
I I I I
—10 It I I I I
0 100 200 300 400 500 600 700 800 900 11 uo 111)0 1200 1300
DISPLACEMENT, cc
FIGURE 4-6 COMPARISON OF F-76 AND J331a NOISE LEVELS, OFF-ROAD (ONLY)
MOTORCYCLES MANUFACTURED 1975-1976.
-------
4 STROKE H
I 300
FIGURE 4-7
D1SPLACEMENT cc
F-50 NOISE LEVELS, STREET AND COMBINATION STREET/OFF-ROAD
MOTORCYCLES MANUFACTURED 1975-1976
= 88.5
= 3.44
= 10
ic = 86.3
a 5.25
n=12
= 89.5
= 5.54
= 89.8
a = 327
n
x
U
90.2
4.4
25
—I
C D
+
20
Ito
- tOO
-J
LU
LU
-J
LU 90
Lf)
-4
C)
C D
b 80
70
60
+
+
0
B
U
0
B
+
0
0
0
I
89.9 + 0.0028x
U
II
0 tOO
200
300
400 500 600
2 STROKE +
1000 1100 1200
-------
120
= 87.25 94.7 = 93.8
ci4.57 +09.5 ci=7.84
n4 n=16
/
110
I I I I
I I t I
I I I I
I + I I
I I I
I I I I
I I I I
1O0 I I + ++
I I I
.
_ 90
-J
w
+ y 88.6+O.O 72x
U i
i+I +1
— I I
CD I I
I I I I
80 I
I $ I I
c) I I
I I I I
LL
I I I
2 STROKE I
I I
I I I
4 STROKE H
70. I I
I I
I I
I I
I I I
I I
I I
I I
60 _ + I 4, 4
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
DISPLACEMENT, cc
‘I1URE 4-8 F-50 NOISE LEVELS, OFF-ROAD (ONLy
MOTORC’YCLES MP NUFACTURED 1975-1976
-------
120
I I
110• I 2 STROKE -f
I I 4STROKE n
100 II
90. 1
I 1
I I I
-c
E i
80 y 71.6 - O.O012x I
1+1
1+ I I [ J
70 I I
1+ DI U
I I 1
I I
60- ___________________________— I -‘-—- ——1— 4
00 200 300 400 500 600 700 800 900 1000 1100 1200 1300
DrsPLAcEMENT, cc
FIGURE 4-9 35 mph NOISE LEVELS, STREET AND COMBiNATION STREET/OFF-ROAD
MOTORCYCLES MANUFACTURED 1975-1976
-------
120
110•
100
90.
80
70.
;= 77.4
= 1.67
‘2
+1
I I
I I
I I
I I
I I
0 100 200 300
-; = 75.0
o = 2.29
;= 74.7
0 2.21
= 10
2 STROKE +
4 STR0V E 1]
y = 78.65 - 0.0044x
+
. . __________________
900 1000 1100 1200 1300
400 500 600
7ó0 800
DISPLACEMENT, cc
55 mph NOISE LEVELS, STREET AND
MOTORCYCLES MANUFACTURED 1
COMBINATION STREET / OFF-ROAD
975-1976
= 79.8
a = 3.77
n= 4
-J
LjJ
I .jJ
—J
U i
c M
C D
E
In
FIGURE 4-10
-------
(d) Noise levels (SAE J331a, F—76, F—77, F—50), by displacement and use
categories; in-service motorcycles, manufactured 1969-1976, modified exhaust
system: Table C-7.
(e) Change in noise levels (SAE J331a, F-76, F-50), referred to original
equipment manufacture (OEM), associated with installation of aftermarket
exhaust systems and user modifications: Table C —b.
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 were obtained at eleven different test sites:
LETTER
CODE _____ LOCATION
A go Th tington B TiT F
B Orange County Fair Grounds, California
c Daytona Beach, Florida
0 Los Alamitos Naval Air Station, California
E Pomona, California
F Houston, Texas
G St. Petersburg, Florida
H Albany, Georgia
Chapel Hill, North Carolina
Suffolk, Virginia
K Ft. Belvoir, Virginia
Test sites B, D, E, H, and U comply fully with the SAE J331a. Recomh1 ended
Practice in all respects; the other sites depart in varying degrees (but were
the best sites available in the respective local areas), Particularly
reference to the requirement for concrete or asphalt ground surfacing between
the vehicle path and the microphone. Oescriptions and photographs of the test
sites are in Appendix B.
In iloving vehicle tests, noise reaches the microphone by two path 5 .
the direct path, and a reflected path, as illustrated below:
Uirect and reflected
noise paths.
SOURCE
-------
410
SOURCE O FEET FROM M1C OrHO (
SOURCE 50 FEET FROM MICROPI1ONE
T s
A
/
/
/
/
‘R(tAlIYt POK!( OF
/ A —WLIGHTIMC P tI Ofl
/
I,
ioe
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. 1/
-h
IODO 10000
FREOUE CY . HERTZ
Di spi acement
50-99 cc
100-169 cc
170-349 cc
350-749 cc
750 cc and over
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 noise source. 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 statis-
tical summaries (as shown on the graphical presentations), the statistics of
Figure 4-1, SAE J331a vs. displacement were re-computed with data from the
non-conforming sites exiuded. Results of this comparison are as follows:
Data from test Data from test
____________ sites A thru K sites B, D, E, H, J
I = 78.0*
0= 4.44
n = 15
I = 81.5
0= 2.95
n = 10
I = 83.1
0= 4.49
n = 23
I = 80.6
0= 2.99
n = 45
1= 81.4 82.3
0= 3.96 4.17
n=28 15
is the mean noise level, dB
is the standard deviation, dB
n is the number of vehicles in the sample
Source I see page 4-29
x=
x=
n=
78.4
3.53
11
80.9
2.27
7
83.6
4.78
19
81.6
2.22
25
4-15
-------
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, II, 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-iS.
Rider Variables
At test site C (Daytona Beach) •each motorcycle was operated by the
owner of the vehicle; rider weight specifications of the SAE J331a 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...
seritative of vehicles currently on the read.
At all of the other sites, the rider was within the 165-175 lb. specifi-
cation. 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 is coninon. Samples taken over a
six-month period by one manufacturer have shown a total variation range of
to 4 dB. The reason for the latter, which may be a seasonal variation has
not been explained. This suggests that a 2 dB allowance between design a,
not-to-exceed levels is an absolute minimum, without considering the need or
a further allowance in the enforcement situation.
Combined Variables Effect
Factors known or suspected to affect measured noise levels include:
(a) Weather variables affecting noise propagation:
— sunny vs overcast sky
- wind velocity/gradient/direction
- temperature and temperature gradients
- barometric pressure
- humidity
(b) Weather variables affecting engine sound power generation:
- barometric pressure
- temperature
- water vapor pressure
- dry barometric pressure
- dry air density
4-16
-------
(c) Manufacturing/assembly/adjustment tolerances affecting engine noise power
generation:
- di ensiona1 variations
- spark timing
- fuel/air mixture
- compression variations
(d) Operation variables:
- engine temperature
- entering RPM or speed (SAE J331a)
- rapidity of throttle opening (SAE J331a)
- entering start point (SAE J331a)
- choice of year selection (SAE J331a)
- closing RPM (SAE J331a and F-76)
- closing point (F-76)
(e) Site variables (site assumed to be in compliance with SAE J331a Recom-
mended 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 (SAE J331a)
- tachometer steady-state accuracy (SAE J331a)
- tachometer dynamic lag (SAE J331a and F-76)
Much work has already been done in assessing the effect of many of
1 ,2/
these variables ; 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.
In addition, in the process of acquiring the noise data base, sub-
stantial information was collected on the effects of contined variables.
Noise level data comparisons between/among vehicles were made in four group-
ings:
(a) Different vehicles of the same model tested at different sites;
(b) Different vehicles of the same model tested at the same site;
tTotes 1 and 2 see page 4-29
4-17
-------
(c) The same vehicle tested at different sites; and
(d) The same vehicle tested at the same site.
The noise level variations (summarized in paragraph 4.3 detafled 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
Noise levels, motorcycles manufactured 1975-1976:
SAE J331a F-76
Displacement Street* Off-Road Street* Off—Road
50-99 cc = 78.0 78.8 77.0 16.4
Ø- 4.64 3.35 4.22 1.82
n=15 5 11 5
100-169 cc = 81.5 91.8 79.5 88.7
0= 2.95 10.11 2.64 10.4
n=10 4 10 3
170-349 cc = 83.1 88.8 81.95 86.8
0’ 4.49 4.96 4.94 5.34
n=23 16 40 16
350-749 cc = 80.5 92.3 81.9
cT= 2.99 3.79 2.63
n=45 3 40
750 cc and Over i = 81.4 85.5
0= 3.96 3.47
n=28 18
Transfer function, F-76 to SAE J331a noise levels (least squares linear
regression line):
y = -2.48 + 0.0066x for street* motorcycles
y = -2.21 * O.0012x for off-road motorcycles
y = F-76 level - SAE J331a level
x = displacement, cc
The F-76 method yields statistical levels 4.1 dB higher than the
J331a method at a displacement of 1000 cc, reducing to 1.9 dB lower at
100 cc for the street machines, with a similar trend in the off-road vehicles.
Includes combination street/off-road motorcycles
4-18
-------
Constant speed 55 mph noise levels as a function of displacement (least
squares linear regression line), motorcycles manufactured 1975—1976:
y = 78.65 - 0.0044x
y = noise level, dB 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 statistically
3.9 dB quieter than motorcycles in the 100-250 cc range, in the 55 mph oper-
ating mode.
Variability in noise level data (from Table C-14); combined effect
of site, rider and vehicle variables:
SAE J331a F—76 F-50
= 0.91 1 = 1.17 1 = 1.21
cr= 1.29 0= 1.58 0= 1.83
n=87 n=69 n=85
Comparison of motorcycles with modified exhaust systems vs. stock
configurations; data from test site C (Daytona Beach) only:
SAE J331a Sound Levels, dB
Motorcycles in Motorcycles with obviously
stock configuration modified exhaust systems
1 =84.4 1=93.6
0 . . = 7.2 0. = 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 organi-
zations 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 afterrnarket manufacturers
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 eval-
uation program of aftermarket exhaust systems. These meeti ngs were attended
4-19
-------
by manufacturer representatives from all parts of the United States, thereby
giving broad exposure to the program.
Subsequently, formal contacts were made with selected afterrnarket
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.
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*
i3assani*
Bates Industries
Butte Industries
Custom Chrome
Cyci one
Dean Maro’s Pipelyne
Di scojet
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 E ngi neeri ng*
Triple—A Accessories*
Winning Performance Products
Aftermarket Exhaust System Testing Program
An important part of the EPA motorcycle noise study involved noise
testing of aftermarket exhaust systems. With the full cooperation and partici
pation 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 motorcycles 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 afterrnarket exhaust systems. In ddjtj to
testing with the applicable aftermarket and stock exhaust systems, variatjo 5
were tested such as removing inserts, baffles, fiberglass, and ifl SO Cases
removing the mufflers altogether, all of which represent forms of mOdified
motorcycles found in circulation.
Toured facility
4-20
-------
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, Trabaca and R.C. Engineering. Figure 4-11 shows some of the exhaust
systems laid out at the test site prior to installation and testing. 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.
Aftermarket Product Study Results
Detailed noise level data on aftermarket and modified exhaust systems
are 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) Noise level data for each configuration designed for the motorcycle
on which tested (aftermarket manufacturer disguised); Table C—la.
A summary of the test results follows.
Aftermarket Exhaust Systems as Configured by the Manufacturer
Noise 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 of the OEM
50 4-16 dB higher than the OEM
The above tabulation excludes configurations designated by the manu-
facturers as “competition” or “racer.” Noise levels of configurations so
designated were as follows:
dB re OEM
+14
+15
+9
+10
4-21
-------
-
FIGURE 411 AFTERMARKET EXHAUST SYSTEMS TO BE TESTED
-------
FIGURE 4-12 INSTALLATION OF AFTERMARKET EXHAUST SYSTEMS PRIOR TO TESTING
P 9
‘ t o
I
-------
Data on mufflers with competition or racer cores are included to illus—
trate the increase in noise 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 streetfoff
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 mu ff1 ers:
dB re OEM
+15
+21
+22
+29
+21
+15
+21
(b) Effect of removing the glass blanket from the removable insert
(insert replaced):
dB re OEM
+4
(c) Effect of removing the OEM muffler:
dB re Stock Config
+22
+19
+16
+20
+ 19
+21
The noise levels resulting from removal of the muffler are indicative
of what could be expected if stock (OEM) or good quality aftermarket 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.
Performance vs. Noise
To illustrate the effect on performance and the effect on noise levels
of aftermarket exhaust systems available for some of the more popular motor
cycles, a comparison Is shown in Table 4-1 of exhaust systems for the HOfld
CB750. Both performance and noise level data were acquired on a variety
systems, including the original equipment. The maximum horsepower and
4-24
-------
torque performance data on this particular motorcycle were obtained on a
dynamoineter, whereas the noise measurements were obtained using the SAE J331a
vehicle acceleration type test procedure. It is apparent from the data that
the aftermarket exhaust systems designed to increase performance over the
original equipment also significantly increase the noise level. Conversely,
the quieter afterrnarket exhaust systems that approach the noise levels pro-
duced 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 exhaust system has improved the motorcycle
performa nce.
Another important point illustrated in Table 4-1 is the availability
of different inserts or cores with the same baseline muffler. Several inanufac—
turers 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 noise 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 motor-
cyclist can remove the noisier high performance insert and replace it with the
street-legal type insert which will comply with existing noise limits.
4.5 Noise 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 conducted a study of
motorcycle noise 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, Harley—Davidson) in
various operating nodes. Measurements were made with the motorcycle station-
ary, on a dynometer and under moving conditions. In addition, measurements
were made 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 f1owing by the ear) is an extremely complex
pheno menon. 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 noise 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 noise exposure for some helmet geometries.
4-25
-------
35.75 @ 7500
38.43 @ 6500
37.68 @ 7500
COMPARISON OF
Table 4-1
AFTERMARKT EXHAUST SYSTEMS FOR HONDA CB7SO
NOISE LEVEL AND PERFORMANCE
EXHAUST SYSTEM
NOISE LEVEL (dB)
MAX. H.P.
Peak Torque
(SAE J331a)
HONDA 750 (OEM)
. ,
81 dB
; . •.-‘
57.67 @ 8500 RPM
36.25 @ 8000 RP
— -
BASSANI (RACING) 4:1
91
BASSANI SMALL 4:1 —
81
55.28 @ 8000
36.12 @ 7000
RJS QUIET CORE
82
RJS STOCK CORE
87
DICK 1 S CYCLE WEST
82
56.89 @ 8500
37.00 @ 6500
-
TRABACA 2:1
89
47.52 @ 7500
35.25 @ 6500
-
37.06 @ 6500
J&R WITH STREET CORE
84
56.0 @ 8000
J&R WiTH COMPETITION CORE
91
60.3 @ 8500
39,25 @ 6500
----------------
38.62 @ 6500
HOOKER 4:1
89
57.92 @ 8500
TORQUE ENGINEERING
83
56.75 Ca 8000
37.93 @ 6500
R.C. ENGINEERING
JARDINE
82
53.6 Ca 8000
87
55.6 @ 8500
37.00
ALPHABETS
83.5
56.6 @ 8500
6500
WINNING
88 59.38 @ 8500
SOURCE: Street Bike — July 1976
‘Honda 750 Header Shoot—Out,”
Jeff Peck
4-26
-------
At this time, motorcycle (alone) noise level (absent wind and helmet
effects) appears to be the best ‘neasure for assessing motorcycle operator
noise impact. Both dynamometer and moving runs indicated that the operator
noise levels under F-76a acceleration conditions were about 100 dB for the
motorcycles tested (SAE J331a valves (50 feet)--Honda: 81 dB, BMW: 81 dB,
Harley-Davidson: 84 dB. Wind noise was below 90 dB 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 condi tions, for the motorcycles tested, motorcycle
(alone) contributions would outweigh wind noise for a helmeted operator.
The extent to which operator ear noise levels would decline as fifty-foo
noise levels declined in response to wayside regulations cannot be confidently
predicted. However, since attention must be given to intake and mechanical
noise (both nearer the operator’s ear than the exhaust noise source), some
reduction is to be expected.
4-27
-------
REFERENCES
1. Hiliquist, R. K. and Bettis, R. A., Fleasurenient of Automotive Pass—by
Noise , paper presented at the SP E Automotive rngFneering Congre
Detroit, Michigan, January 10—14, 1972.
2. Hemdal, John F., et al., A Study of Repeatability at Motor Vehicle
Noise Measurement Sites , EnvTronniental Research Institute of T iT ãi
1974.
4-28
-------
SECTION 5
EVALUATION OF EFFECTS OF frOTORCYCLE NOISE
ON PUBLIC HEALTH As JD WELFARE
-------
SECTION 5
EVALUATION OF EFFECTS OF MOTORCYCLE
NOISE ON PUBLIC HEALTH AND WELFARE
5.1 Introduction
The purpose of this section is to assess, in quantitative terms, the
health and welfare impact of the noise emitted by motorcycles, and the bene-
fits or reductions in this impact to be expected from a regulation limiting
the noise emissions from newly manufactured motorcycles. Presented in this
analysis are predictions of the potential health and welfare benefits of
selected noise control options that cover a wide range of possible regulatory
programs for motorcycles.
Because of inherent differences in individual responses to noise, the
wide range of situations and environments which relate to motorcycle noise
generation, and the complexity of the associated noise fields, it is not
possible to precisely examine all situations of comunity exposure to motor-
cycle noise. In this predictive analysis, certain stated assumptions have
been made in order to approximate typical, or average, situations. The order
of magnitude of the population that may be affected for each regulatory option
is determined through statistical analysis. Some uncertainties with respect
to individual cases or situations may remain.
5.1.1 Effects of Noise on People
The phrase Hhealth and welfare, as used in this analysis and in the
context of the Noise Control Act, is a broad term. It includes personal
comfort and well-being and the absence of mental anguish, disturbances and
annoyance, as well as the nonoccurrence of clinical s ptoms such as hearing
loss or demonstrable physiological injury (Reference 1). In other words,
the term applies to the entire range of adverse effects that noise can have
on people.
Improvements in public health and welfare are regarded as benefits of
noise control. Public health and welfare benefits may be estimated both
in terms of reductions in noise exposure and, more meaningfully, in terms
of reductions in adverse effects. This analysis first estimates motorcycle
noise exposure (numbers of people exposed to different noise levels), and then
translates this exposure into potential impacts on the coinnunity.
People are exposed to noise from motorcycles in a variety of situations.
Some examples are:
1. Inside a home, office or workplace
2. Outdoors at home, or in coinnercial and industrial areas
5—1
-------
3. As a pedestrian or in transit in other vehicles
4. As a participant in recreational activities
5. As a motorcycle operator or passenger
Noise affects people in many ways, although not all noise effects will
occur at all levels. Noise associated with motorcycles may or may not produce
the effects mentioned below, the extent to which depends on duration of
exposures and specific noise exposure situations.
The best—known noise effect, noise-induced hearing loss, is generally not
a problem for a person with occasional exposure to traffic noise. A charac-
teristic of noise—induced hearing loss is that it first occurs in the high—
frequency area of the auditory range which has some importance for the under-
standing of speech. As a noise-induced hearing loss further develops, the
sounds which lend meaning to speech become less and less discriminable.
Eventually, while utterances are still heard, they become merely a series of
low rumbles, and the intelligibility is lost. Noise-induced hearing loss
is a permanent loss for which hearing aids and medical procedures cannot
compensate.
Exposure to noise can cause stress. The body has a basic, primitive
response mechanism which automatically reacts to noise as if to a warning or
danger signal. A complex series of bodily reactions (sometimes called the
“1 light-or-f ight” response) takes place; these reactions are beyond COflSCIOUS
control. When noise intrudes, these reactions can include elevation of blood
pressure, changes in heart rate, secretions of certain hormones into the
bloodstream, changes in digestive processes, and increased perspiration on the
skin.
This stress response occurs with individual noise events, but it is not
known yet whether the reactions seen in the short term become, or contribute
to, long-term stress disease such as chronic high blood pressure.
Some of this stress response is believed to be reflected in what people
express as “annoyance’, “irritation”, or “aggravation” and which the Agency
has termed “general adverse response”. Accordingly, this analysis estimates
the generalized adverse responses of people to environmental noise. To the
extent that physiological stress and verbalized annoyance are related, the
“general adverse response” quantity is considered to be one metric for mdi..
cating the magnitude of human stress response.
The general adverse response relationship to noise levels is also seen as
representing, in part, another area of noise effects: activity interference
There is considerable scientific data that demonstrate that noise interferes
with many important daily activities such as sleep and verbal conl’nunicatjon
(Reference 2). [ n expressing the causes of annoyance to noise, people Often
report that noise interferes with sleeping, relaxing, concentration, TV and
radio listening, and face—to-face and telephone communications. Thus, the
general adverse response quantity is considered an appropriate metric to mdi...
cate the severity to which noise interferes with everyday human activities.
5—2
-------
5.1.2 Measures of Benefits to Public Health and Welfare
People are exposed to noise generated from motorcycles both at and away
from their residences. In general, it is anticipated that a reduction of
noise emitted from motorcycles will result in the following types of bene-
fits:
1. Reduction in average traffic noise levels and associated cumula-
tive long-term impact upon the exposed population.
2. Fewer human activities disrupted by individual, intense or intruding
noise events.
3. General improvement in the quality of life, with quiet as a national
resource.
The general approach taken in this health and welfare regulatory analysis
is to estimate the adverse effects of motorcycle noise on the U.S. population,
and then quantitatively evaluate the potential benefits resulting from the
reduction of noise from motorcycles in terms of percentage reductions in
adverse impact.
Estimates of traffic noise levels are presented in terms of the noise
levels associated with typical motorcycle passbys. These estimates are
derived by considering traffic mixes within different populated land areas.
Possible reductions in average traffic noise levels from current conditions
(i.e., without noise emission regulations for motorcycles) are presented for
several regulatory options for new motorcycles, taking into account probable
noise emission reductions of other traffic noise sources (References 3 and
4). Projections of the population adversely impacted, as well as the rela-
tive reductions in impact (benefits) from current conditions, are determined
from the estimated reductions in average traffic noise levels.
However, estimating nationwide Impact in terms of average urban traffic
noise levels is not, in and of itself, totally indicative of the severity or
extensiveness of the motorcycle noise problem. The analysis does not fully
describe individual disturbances or the extreme annoyance caused by single
motorcycle passbys in various environmental situations. This Is because
annoyance or other responses to noise frequently depend on the activities and
locations of the people when exposed to such noise. Thus, average traffic
noise levels do not account for the more disruptive and annoying peak noise
intrusions produced by individual motorcycle passbys (frequently referred to
as “single events”). Therefore, additional potential benefits should result
from the reduced noise levels associated with these single events. These
benefits are discussed in terms of the potential interference with people’s
activities. Sleep interference and speech interference are considered in this
analysis as Indicators of potential activity interference and the associated
adverse impact of motorcycle noise.
The following analysis presents numeric values which represent both the
numbers of people exposed to motorcycle noise and the degree to which they are
potentially impacted. Also presented are relative percentage reductions in
5-3
-------
impact from 1980 conditions. This analysis relies primarily on relative
percent reductions in noise impact as a measure of benefit. The relative
reductions in impacts are considered accurate indicators of what might be
expected from the imposition of noise emission standards. For example, while
it may not be possible to characterize completely the extensiveness and
severity of the noise impact of current motorcycle operations, relative
reductions can be accurately calculated and are used for comparing various
regulatory alternatives.
5.1.3 Regulatory Schedules
The health and welfare analysis carried out for motorcycles examined
the potential benefits of reducing motorcycle noise based upon a broad range
of regulatory options. The regulatory options shown in Table 5-1 represent
those options that were considered in arriving at the final regulatory levels
and effective dates. Option Q (an idealized case) represents the quieting of
motorcycles to a level 10 dB below the most stringent regulatory option. This
option is included for comparison purposes only to indicate an upper limit of
potential benefits.
5.2 Description of Traffic Noise Impact
This analysis presents projections of average traffic passby noise levels
for scenarios that include both urban street traffic and highway traffic.
Note that the adverse impact from traffic noise is primarily due to traffic
on urban streets as opposed to highways and freeways.
As presented in Figure 5-1, the number of people exposed to outdoor noise
levels that are greater than L, * of 55 dB dominated by urban street traffic
noise is significantly higher t’?i’an the number exposed to highway and freeway
traffic noise -- 78 million as opposed to 17 million. Thus, reducing urban
Street traffic noise will benefit significantly more people than will similar
reductions in highway traffic noise.
5.2.1 Street Motorcycles
In this section of the health and welfare analysis, current street
motorcycle sound levels, as well as sound levels under various possible noise
emission regulations on motorcycles that are ridden on streets and highways
are examined. This includes both street and dual-purpose bikes. (Motorcycie
that are ridden off—road are examined separately in Sections 59 through
5.12).
sound level expressed in decibels. This Is discussed
in more detail In Section 5.3.2.
5-4
-------
TABLE 5—1
REGULATORY OPTIONS ANALYZED FOR STREET MOTORCYCLES
Effective
Date
Option
Number
1982
1984
1985
1987
1990
1991
1996
1
--
--
BASELINE
(NO
REGULATION)
-—
--
2
83
--
--
--
- -
--
- -
3
83
80
--
--
--
--
--
4
83
--
80
- -
- -
--
- -
5
83
80
--
78
--
--
--
6
83
80
--
--
78
--
--
7
83
--
80
78
--
--
--
8
83
--
80
--
78
--
--
9
83
80
--
78
--
75
--
10
83
--
80
--
78
--
75
Q*
65
--
--
- -
--
--
--
Not-to—exceed sound levels in decIbels (A-weighted) as measured by the
Federal test procedure. Production levels are assumed to be 2.5 dB lower
than these regulatory levels, as discussed in Section 5.2.1.2.
*Option Q is set 10 dB below the most stringent regulatory option. It Is an
idealistic option intended for comparison purposes only.
5-5
-------
( I )
z
0
-J
-J
C
uJ
F —
C - )
C
0
a
0
F-
C
-J
3-
0
0 -
FIGURE 5—1
ESTIMATED NUMBER OF PEOPLE IN RESIDENTIAL AREAS CURRENTLY
SUBJECTED TO TRAFFIC NOISE ABOVE Ldn = 55 dB
>55 >61 >64 >70 >76
5-6
-------
5.2.1.1 Current Street Motorcycle Sound Levels
A statistical representation of stock motorcycle sound levels, based
on the data in Appendix C, is presented in Fiqure 5-2. These data are the
maximum sound levels as measured by the SAE J—331a test procedure. This
procedure is representative of very rapid acceleration from 30 mph (full-
throttle, high engine speed). The maximum sound levels as measured by SAE
3-331a procedure can be adjusted to account for more commonly encountered
acceleration modes (partial-throttle and moderately high engine speed). As
discussed in Section 3, sound levels as measured by the regulatory test
procedure are assumed to be statistically equivalent to SAE J-331a levels.
Cruise sound levels are based on steady-state operation at various constant
speeds.
The data in Figure 5-2 were developed from noise measurements of 200
unmodified motorcycles that 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 that; did not differ significantly from the
distribution shown in Figure 5-2. Hence, Figure 5—2 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 (Reference 5), at least 12 percent of
street motorcycles and dual-purpose motorcycles (treated in this analysis as
street motorcycles), and 26 percent of off-road motorcycles have modified
exhaust systems. (In Los Angeles and Sari Francisco, these percentages were
higher, approximately 15, 13, and 47 percent 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 syste i odifications are typically the most
noticeable form of motorcycle noise tampering.
In this analysis, statistics are developed by using several different
assumptions on the incidence of modified motorcycles. The current incidence,
unchanged by Federal regulation (12%), and two lower incidences (7% and
3%) are modeled for street motorcycles to reflect the expected reduction
of exhaust modifications. Eliminating motorcycle modifications entirely,
however, is not considered to be feasible with even the most vigorous com-
mitment to noise enforcement by Federal, state , and local governments.
Reduction of modified motorcycles to about half the current incidence (7% of
the population) is the expected reduction through Federal regulation alone.
Reduction to about one quarter of the current incidence (3%) is considered to
be the reduction achievable from a combination of Federal regulation and
vigorous state and local enforcement programs.
The sound levels of 19 known exhaust-modified (noncompetition) motor-
cycles are plotted in Figure 5—3. The best fit of a normal distribution to
the data is indicated by the straight line. In comparison with the SAE J—331a
test results for unmodified motorcycles shown in Figure 5.2, it can be seen
5—7
-------
95
MEAN 80.4 dB
STANDARD DEVIATION 3.7 dB
1
FIGURE 5-2
10 20 30 40 53 63 70 80 90
PERCEN’ EXCEEDING SOUND LEVEL.
PERCENT OF IJNMODIrIED STREET MOTORCYCLES WICH EXCEED ANY
GIVEN SOUND EVEL.
SOURCE: APPEND C
23
T
w
uJ
LU
LU
LL
I .—
LU
LU
L)
L)
LU
-J
LU
LU
-J
0
70
60
99
5-8
-------
MEAN = 94.0 dB
STANDARD DEVIATION 5.3 dB
1 10 20 30 40 50 60 70 CO CO 99
SOURCE: APPENDIX C
PERCENT EXCEEDING SOUND LEVEl
FIGURE 5-3 PERCENT OF MODIFIED MOTORCYCLES WHICH
EXCEED ANY GIVEN A—WEIGHTED SOUND LEVEL
C ,,
w
I —
=
(D
LU
- 4
I—
IL l
LU
U-
I—
-4
I—
LU
-J
LU
C-,
C-,
LU
=
-J
w
LU
-J
I,,
90
5-9
-------
that the mean sound level for exhaust-modified motorcycles is 13.6 dB greater
than that for unmodified motorcycles. The distribution of sound levels also
shows a greater dispersion, with a standard deviation of 5.3 dB for modified
motorcycles as compared to 3.7 dB for the unmodified motorcycles. These
results are confirmed by previous measurements of both unmodified and exhaust—
modified motorcycles. It is apparent that modified motorcycles are typically
much louder than unmodified motorcycles. Since increasing a sound level by 12
dB increases the distance 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 propaga-
tion losses), it Is apparent that motorcycles with modified exhaust systems
contribute to the overall noise impact from motorcycles in much larger propor-
tion than their actual numbers would indicate.
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 tlme* is given by:
Leq = L 50 + O.115 (1)
where L 50 is the median noise level, and is the standard deviation (Refer-
ence 6). In this analysis of traffic noise impact, it is assumed that
the distribution of maximum roadside sound levels for each type of vehicle Is
approximated by a normal (Gaussian) distribution. This assumption permits
calculation of the energy-average of the maximum sound levels from median
value of the maximum sound levels in a manner similar to the computation of
Leq in Equation 1. That is:
La = L 50 + O.115cT 2 (2)
where L is the energy-average of the maximum sound levels, L is the
median v alue of the maximum sound levels, and C is the standard de ?atlon of
the maximum sound levels. As Equation 2 demonstrates, the energy-averaged
maximum sound level depends on both the median level and standard deviation of
the levels. The energy-average maximum sound levels that are used in the
following analysis are shown in Table 5-2. In the computation of energy...
averaged maximum noise levels, it is assumed that normal (partial throttle)
acceleration levels are 3 dB less than the measured SAE J-331a test levels
(see Appendix 6).
The representative energy-average maximum noise level can be used to
derive the various noise levels emitted by motorcycles In different modes o
operation. The methodology for these derivations is contained in Reference
7. The current or baseline noise levels for street motorcycles that have not
been regulated are shown in Table 5-3.
*Leq is the equivalent A-weighted sound level in decibels. This is
in more detail in section 5.3.1.
5-10
-------
TABLE 5-2
Full-Throttle
Acceleration
(J-331a)
(median level)
Representative
Acceleration
(J—331a — 3 dB)
(median level)
Standard
Deviation
Energy-Averaged
Representative
Acceleration
(from Eq 2)
A—WEIGHTED MAXIMUM SOUND LEVELS IN DECIBELS FOR MOTORCYCLES IN USE
(CURRENTLY AND IN THE NEAR FUTURE, IF UNREGULATED)
35 mph
Cruise
p- i
Unmodified 71.5
80.4
77.4
3.7
79.0
Motorcycles
Designed for
Street Use
Exhaust- 84.0
94.0
91.0
5.3
94.2
Mod if led
Motorcycles
SOURCE: Appendices C & G.
The 35 MPH
cruise noise level for
modified motorcycles
is
assumed to be
10
dB
lower than
the J331a noise level
based on the studies
discussed in Appendix 6.
-------
TABLE 5—3
BASELINE A—WEIGHTED NOISE LEVELS (IN DECIBELS) FOR
VARIOUS MODES OF OPERATION OF STREET MOTORCYCLES
Mode of Unmodified Modified
Operation Motorcycles Motorcycles
Acceleration
0—20 mph 72.3 87.5
0—30 “ 73.9 89.1
0-40 “ 74.4 89.6
0—50 “ 74.7 89.9
0-60 74.9 90.1
Deceleration
20—0 mph 61.5 75.7
30-0 65.9 80.1
40—0 “ 69.0 83.2
50—0 “ 71.4 85.6
60-0 “ 73.4 87.6
Cruise
< 25 mph 66.9 81.1
24—34 71.3 85.5
35-44 1 74.4 88.6
45-54 “ 76.9 91.1
> 55 ‘I 78.9 93.1
Idle 58.9 72.0
5-12
-------
5.2.1.2 Noise Emission Levels of Regulated Street Motorcycles
In order to predict the effect that a motorcycle noise emission regula-
tion will have on actual motorcycle noise emissions, some assumptions must be
made as to the changes that would occur in the sound levels presented in Fig-
ures 5-2 and 5-3 (for unregulated motorcycles) due to a particular regulatory
standard. It is expected that to comply with a Federal noise regulation,
manufacturers will produce motorcycles with average sound levels about 2.5 dB
lower than the regulatory limits to account for production and testing vari-
abilities (see Chapter 6). For modeling purposes, the production level is
assumed to be the median value for a distribution of maximum sound levels for
new motorcycles having a standard deviation of 2.5 dB.
Using the above stated assumptions, future production motorcycle sound
levels are estimated for the different regulatory options as shown in Figure
5—4. The statistical distributions of sound levels for the regulatory options
illustrated in Figure 5-4 are developed on the assumption that manufacturers
will not further quiet motorcycles which already meet noise standards.
Anticipated noise emission levels for each mode of operation of motorcycles
regulated to levels of 83 dB, 80 dB, 78 dB, and 75 dB are shown in Table 5-4.
These representative noise emission levels under each operational mode were
derived according to the procedures of Reference 7.
After implementation of a noise emission regulation for motorcycles, it
is expected that as more and more older unregulated motorcycles are replaced
by new regulated motorcycles, the population averaged acceleration sound
levels will also be reduced over time. For example, suppose a regulation was
promulgated which provided that no new motorcycle for Street use could exceed
80 dB, according to the SAE J—331a test procedure. The motorcycles above this
sound level, which comprise the “loudest” 56 percent of the unmodified street—
use motorcycles shown in Figure 5—4, would eventually disappear as quieter
motorcycles replace older models. Eventually a new distribution would be
formed in which no unmodified street-use motorcycle would exceed the 80 dB
standard as measured by the SAE J-331a test, and the mean level would decrease
accordingly.
5.2.1.3 Motor Vehicle Noise
To better identify those circumstances in which street motorcycles
cause significant noise impact, it is necessary to relate motorcycle sound
level distributions for other traffic vehicles.
Table 5—5 presents the current (1979) levels of all vehicles in the
traffic stream for several modes of operation. Seven categories of light
vehicles and automobiles are regulated with respect to noise. The noise
emission levels presented for the two categories of trucks represent the
levels associated with the 83 dB noise regulation, which became effective
in 1978. By 1982, medium and heavy trucks will be required to meet a regu—
latory limit of 80 dB, as measured by the SAE J-336b test procedure. The
levels presented for buses are unregulated levels, although they, too, will be
regulated to lower levels in the near future.
5—13
-------
NOTE: ASSUMES VARIOUS REGULATORY STUDY LIMITS:
PRODUCTION LEVEL IS 2.5 dB BELOW REGULATORY LEVEL
10 20 30 40 50 60 70
PERCENT EXCEEDiNG SOUND LEVEL
80 90
FIGURE 5-4 STATISTICAL DISTRIBUTION OF ACCELERATION SOUND LEVELS OF
STREET MOTORCYCLES
100
95
90
85
I —
uJ
L1
Lfl
0
I—
U i
-J
U i
(-)
C-)
Ui
-I.
LU
V.,
80
75
*STUDy LEVELS
70
99
5-14
-------
TABLE 5—4
IN-USE A—WEIGHTED NOISE EMISSION LEVELS (IN DECIBELS) FOR REGULATED AND UNREGULATED MOTORCYLES
Unmodified Motorcycles Modified Motorcycles
Acceleration Mode Acceleration Mode
Mode of No Mode of No
Operation Regulation 83 dB 80 dB 78 dB 75 dB Operation Regulation
0—20 mph 72.3 71.5 68.5 66.5 63.5 0—20 mph 87.5
0-30 73.9 73.1 70.1 68.1 65.1 0—30 “ 89.1
0-40 “ 74.4 73.6 70.6 68.6 65.6 0—40 89.6
0-50 “ 74 7 73.9 70 9 68 9 65 9 0-50 “ 89 9
0-60 74.9 74.1 71.1 69.1 66.1 0—60 “ 90.1
Deceleration Mode Deceleration Mode
Mode of No Mode of No
Operation Regulation 83 dB 80 dB 78 dB 75 dB Operation Regulation
20—0 mph 61.5 60.7 57.7 55.7 52.7 20-0 mph 75.7
30-0 “ 65.9 65.1 62.1 60.1 57.1 30-0 80.1
0 40-0 69.0 68.2 65.2 63.2 60.2 40-0 “ 83.2
50-0 ‘ 71.4 70.6 67.6 65.6 62.6 50—0 “ 85.6
60-0 “ 73.4 72.6 69.6 67.6 64.6 60-0 ‘ 87.6
Cruise Mode Cruise Mode
Mode of No Mode of No
Operation Regulation 83 dB 80 dB 78 dB 75 dB Operation Regulation
<25 mph 66.9 66.1 63.1 61.1 58.1 <25 mph 81.1
24—34 71.3 70.5 67.5 65.5 62.5 25—34 “ 85.5
35—44 74.4 73.6 70.6 68.6 65.6 35-44 “ 88.6
45—54 76.9 76.1 73.1 71.1 68.1 45-54 “ 91.1
>55 78.9 78.1 75.1 73.1 70.1 >55 93.1
Idle Mode Idle Mode
Mode of No Mode of No
Operation Regulation 83 dB 80 dB 78 dB 75 dB Operation Regulation
58.9 58.3 55.3 53.3 50.3 72.0
-------
TABLE 5-5
BASELINE VEHICLE A—WEIGHTED NOISE EMISSION LEVELS (IN dB)
Intercity
Buses
Transit
Buses
School
Buses
Light
Vehicles
Medium
Trucks
Heavy
Trucks
Unmodified
Motorcycles
Modified
Motorcycles
Acceleration
0—20 mph
81.6
81.0
77.6
63.3
75.1
82.7
72.3
87.5
0—30 ‘
82.0
81.0
78.1
65.1
75.6
82.8
73.9
89.1
0—40 “
82.3
81.1
18.4
66.5
76.2
83.0
74.4
89.6
0—50 “
82.6
81.2
78.9
68.2
76.8
83.4
74.7
89.9
0—60 ‘
82.8
81.5
79.4
69.9
77.7
84.0
74.9
90.1
Deceleration
20-0 mph
68.1
63.7
63.7
53.4
65.8
73.9
61.5
75.7
30-0
71.4
67.8
67.8
59.0
70.0
77.3
65.9
80.1
40-0
73.8
70.6
70.6
63.0
73.0
79.6
69.0
83.2
50—0 “
75.6
72.9
72.9
66.1
75.1
81.4
71.4
85.6
60—0
77.1
74.1
74.7
68.7
76.8
82.7
73.4
87.6
Cruise
<25 mph
76.0
73.0
73.0
62.7
77.2
83.6
66.9
81.1
24—34
76.0
73.0
73.0
65.3
77.2
83.4
71.3
85.5
35—44 I’
78.4
75.8
75.8
69.3
78.1
84.2
74.4
88.6
45—54 “
80.2
78.1
78.1
72.4
80.2
85.7
76.9
91.1
>55
81.7
79.9
79.9
74.9
81.7
86.8
78.9
93.1
Idle
62.0
58.0
58.0
46.0
54.0
63.0
58.9
72.0
*passenger cars and light trucks with four cylinder gasoline engine and manual transmission.
-------
It can be seen from Table 5-5 that modified motorcycles are the noisiest
vehicles under all conditions. As noise emission regulations for other
vehicles take effect, the differences between modified motorcycles and other
vehicles will increase further.
5.3 Noise Metrics
In this analysis, two methods are used to evaluate the health and welfare
benefits of reduced motorcycle noise emissions. These methods estimate the
general adverse response due to noise associated with the operation of motor-
cycles and the potential of everyday activity interference (sleep disturbances
and speech interferences) attributable to individual motorcycle passbys.
Three noise metrics are principally used in these methods. The primary
measures of noise exposure for general adverse response and annoyance are the
Equivalent A-weighted Sound Level (Lea) and the Day-Night Sound Level Ldn).
Potential sleep disturbances are computed using the Sound Exposure Level (La)
of the individual event as the primary measure of noise impact. Speech inter-
ference is calculated using the Leq over the duration of the individual noise
event. A brief description of these three noise metrics follows.
5.3.1 Equivalent Sound Level, Leq
This analysis uses a noise measure that condenses the physical acoustic
properties that are characteristic of a given noise environment into a simple
indicator of the quality and quantity of noise. This general measure for
environmental noise is the equivalent A-weighted sound level (Leq) expressed
in decibels (Reference 8). It correlates quite well with the overall long-
term effects of environmental noise on public health and welfare.
The basic definmtion of Leq is:
L 10 lo ________ ,2 (t ) .dt
eq t 2 — 1 10 p 2 3
where (t 2 — t 1 ) is the interval of time over which the levels are evaluated,
p (t) is the time—varying magnitude of the sound pressure, and p 0 is a refer-
ence pressure standardized at 20 micropascals. When expressed in terms of A-
weighted sound level, LA, the equivalent •4 -weighted sound level, Leq is
defined as:
Leq = 10 log 10 2 lO [ LA(t)/lO] .dt (4)
5—17
-------
When associated with a specific short-time interval, (t 2 —t 1 ), or T, the
Leq (T) represents the energy-averaged sound level over that interval of time.
Cormionly used time intervals are 24-hour, 8-hour, 1—hour, day and night, sym-
bolized as Leq(24) , Leq(8) , Leq(1) Ld and L , respectively.
5.3.2 Day—Night Sound Level, Ldn
In describing the impact or noise on people, a measure called the day—
night sound level (Ldn) is used. This is a 24-hour measure with a weighting
applied to nighttime noise levels to account for the increased sensitivity of
people to noise intruding at night. The Ldn is defined as the equivalent
noise level during a 24—hour period, with a 10 dB weighting applied to the
equivalent noise level during the nighttime hours of 10 p.m. to 7 a.rn. The
basic definition of Ldn in terms of the A-weighted sound level is:
2200 0700
Ldn 10 log 10 24 LA(t)/lO .dt +5 LA(t)+10)/10 .dt) (5)
0700 2200
When values for average or equivalent sound levels during the daytime or
nighttime hours (Ld and L , respectively) are given, Ldn may be expressed
as:
/ Ld/10 (L + 10)/10
Ldn 10 log 10 (15 X 10 + 9 X 10
24 \ (6)
where Ld is the °daytime” equivalent level obtained between 7 a.m. and io
p.m., and L is the “nighttime” equivalent level obtained between 10 p.m. and
7 a.m.
5.3.3 Sound Exposure Level, L 5
Most of the criteria which relate noise exposure to adverse human impact
deals with people’s exposure to noise over time rather than to discrete noise
events. Specification of the noise environment in terms of day-night Sound
level is adequate for pervasive, long-term type noises, such as genera’
traffic noise or aircraft noise. However, such measures may not be fully
descriptive of the ‘impact of the noise from single, isolated occurrences, such
as a motorcycle passing by. In this case, a single noise event may contribute
an insignificant amount to the total environmental noise, yet be of signjfj_
cant adverse impact. Some effects of noise on people have been quantjfj
in terms of sound level (such as 1 eq) over a particular duration. Others have
been quantified by a simple metric which measures total sound energy over the
duration of the event, the Sound Exposure Level (L 5 ). The sound exposure
level is the integral of the mean square weighted sound pressure received at a
specified distance during a single occurrence of a noise-producing event. The
sound exposure level is defined as:
5-18
-------
L 5 10 log 10 fT p 2 t ) dt (7)
p 0
where p(t) is the A-weighted sound pressure at time t, p 0 is the reference
pressure (20 micropascals), and T is the duration of the noise event. For
a typical motorcycle passby, the approximation to the sound exposure level
is:
L 5 = Lmax + 10 log 10 (1/2.4) (8)
where T is the time in seconds over which the sound is present (within 10 dB
of the maximum level experienced during the passby), and Lmax is the maximum
A-weighted sound level of the event (a more detailed description of the time
history approximation may be found in reference 31).
5.4 Fractional Impact Method : See Appendix M
5.5 Health and Welfare Criteria - General Adverse Response
To project the potential benefits of reducing the noise from motorcycles,
it is necessary to describe statistically the noise-exposed population (on a
national basis) both before and after implementation of the regulation. This
statistical description characterizes the noise exposure distribution of the
population by estimating the number of people exposed to different magnitudes
of noise as defined by metrics such as day-night sound level. This is concep-
tually illustrated in Figure M-1 of Appendix M, which compares the estimated
distribution of the noise exposed population before and after implementation
of a hypothetical regulation. This type of approach provides a basis for
evaluating the change in noise impact due to a given regulatory action.
It is also necessary to distinguish, in a quantitative manner, between
the differing magnitudes of impact upon different individuals exposed to
different values of L, . That is, the magnitude of human response to noise
generally increases pr’ gressively from an identified “no response” threshold
to some extreme maximum projected impact -- the greater the exposure, the
more extreme the response. Hence, once the identified level is exceeded,
the degree of human response associated with the noise will increase with
Increased noise exposure.
To assess the impact of traffic noise using the fractional impact proce-
dure, one needs a relation between the changes in traffic noise and the
responses of the people exposed to the noise. There exists some variability
In human response measures due to a number of social and demographic factors.
In the aggregate, however, for residential locations, the average response
of groups of people is related quite well to cumulative noise exposure as
expressed in a measure such as L, . For example, the different forms of
response to noise such as hearing ámage, speech or other activity Interfer-
ence, and annoyance were related to Leq or Ldfl in the EPA Levels Document
5-19
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(Reference 8). For the purposes of this part of the study, criteria based on
Ldn presented in the EPA Levels Document are used. Furthermore, it is assumed
for this analysis that if the outdoor level of dn S less than or equal to 55
dB, which is identified in the EPA Levels Document as requisite to protect the
public health and welfare, no adverse impact in terms of general annoyance and
community response exists.
The community reaction data presented in Appendix D of the EPA Levels
Document (Reference 8) show that the expected reaction to an identifiable
source of intruding noise changes from “none” to “vigorous” when the day—night
sound level increases from 5 dB below the level existing without the presence
of the intruding noise to about 20 dB above the level before intrusion. For
this reason, a level of 20 dB above Ldn = 55 dB is considered to result in a
vigorous reaction by the people exposed. At this level (Ldn = 75 dB), the
percentage of the population which is “highly annoyed” by noise would be
approximately 40 percent of the total exposed population. The data in the
EPA Levels Document suggest that for environmental noise levels which are
intermediate between 0 and 20 dB above Ldn 55 dB, the impact varies lin-
early. That is, a 5 dB increase (Lcjn = 60 dB) constitutes a 25 percent
impact, and 10 dB increase (Ldn = 65 dB) constitutes a 50 percent impact, with
a 20 dB increase representing maximum impact.
For convenience of calculation, a function for weighting the magnitude of
noise impact with respect to general adverse reaction (annoyance) has been
used (Figure 5-5). This function, normalized to unity at Ldn = 75 dB (a point
of maximum expected impact for most communities), may be expressed as repre-
senting percentages of impact in accordance with the following equation:
(0.05 (Ldn - C) for Ldn > C
W(Ldn) = (9)
0 forLdn
-------
1
3
>-
0
z
z
>-
-j
I
I
I-
w
0
w
FIGURE 5—5
COMPARISON OF CURVILINEAR FUNCTION AND
FRACTIONAL IMPACT LINEAR FUNCTION
1.50
I—
1.25 0
0
1.00
0.75
0.50
0.25 t
U..
Ldfl (DECIBELS)
5-21
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associated with a given level of traffic noise (L dn) may be obtained (Refer-
ence 9). The procedure involves multiplying the number of people exposed to
that level of traffic noise by the relative weighting associated with this
level as follows:
LWPj = W(L”dn) P 1 (10)
where LWP 1 is the magnitude of the impact on the population exposed to traffic
noise L dn and is numerically equal to the number of people who would all have
a fractional impact equal to unity (100 percent impacted). W(L 1 dfl) is the
weighting associated with an equivalent traffic noise level of L’dn (from
equation 9), and Pj is the population exposed to that 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, W(Ldn) = 0.25), the environmental noise impact for
this group is the same as the impact on 250 people who are 100 percent
impacted (1000 x 25% = 250 x 100%). A conceptual example is portrayed in
Figure 5-6.
When the total impact associated with traffic noise is assessed, the
observed levels of noise generally decrease as the distance between the source
and receiver increases. The magnitude of the total impact may be computed by
determining the partial impact at each level and summing over each of the
levels. The total impact is given in terms of Level Weighted Population by
the following formula:
LWP = CLWP 1 = Z [ W(L ) x P.s] (11)
where W(L dn) is the fractional weighting associated with L’dn, and P 1 is
the population exposed at each L 1 dn.
The change in impact associated with regulations on the noise emissions
from traffic vehicles may be assessed by comparing the magnitude of the
impacts with and without regulations in terms of the Relative Change in Impact
(RCI), which is calculated from the following expression:
[ LWP (before) - LWP (after) ]
RCI 100 x LWP (before) (12)
This basic fractional impact procedure is also used to compute noise
impact employing a variety of additional criteria (e.g., activity lnter
ference, hearing damage risk, etc.) other than general adverse response
(Reference 11).
As discussed previously, the concept of fractional impact, expressed m
units of LWP, is most useful for describing relative changes in impact from a
spec ified baseline for the purpose of comparing benefits of alternative
5—22
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0
FIGURE 5-6. EXAMPLE OF FRACTIONAL IMPACT METHODOLOGY
The computation of LWP allows one to combine the number of people jeopardized
by noise above an Ldn of 55 dB with the degree of impact at different noise
levels. The circle is a source which emits noise to a populated area. The
various partial amounts of shading represent various degrees of partial impact
by the noise. The partial impacts are summed to give the LWP. In this
example, six people who are adversely affected by the noise (partially shaded)
results in a level weighted population (LWP) of two (totally shaded).
5-23
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regulatory schedules. In order to assess the absolute impact or benefits
corresponding to any regulatory schedule, one must have information on the
distribution of population as a function of noise environment. The deriva-
tion of this type of information is discussed in Section 5.7.
5.6 Health and Welfare Criteria-Siflgl Event Response
When the benefits of lessening the noise from motorcycles are being
examined, it is important to look beyond the contribution that motorcycles
make to overall average day—night traffic noise (LA., ). The impact contribu-
tions which are calculated in terms of average comrniiWity response are somewhat
generalized and do not necessarily represent specific impact situations. On
some occasions, noise associated with motorcycles will combine with other
noises, as described by the General Adverse Response analysis. At other times
or in other situations, one can expect that other noise sources will not be
significant, and thus each motorcycle passby will cause a distinct impact.
The actual impact from motorcycles is certainly due to a combination of vari-
ous levels of motorcycle noise and other environmental noise. Thus, the
methodology for assessing general adverse response (as discussed in Section
5.5) will not take into account the fact that almost the entire amount of
daily acoustical energy contributed by motorcycles in an area may be generated
by only a few minutes of noise during many accelerations near an intersection
in the course of a day. Yet these intrusive, short, intense events may be
some of the most annoying noise-related situations faced over the entire day
by a large number of pedestrians or residents.
It is difficult to derive a direct measure of the annoyance attributable
to the intrusiveness of motorcycle noise. Numerous surveys indicate that
motorcycle noise is a major source of annoyance but only a few scientific
studies have directly related motorcycle sound levels to degrees of annoyance.
When queried in attitudinal surveys, respondents generally rate motor-
cycle noise as a major, If not the major, source of annoyance from traffjc
related noise. For example, the response to noise survey queStionnajr 5
mailed to a random sample of individuals showed that the respondents rated
motorcycles 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 (Reference
12).
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 percentage of people and
were rated as “extremely bothering” by the highest percentage of people.
A total of 44.8 percent rated motorcycle noise as either “moderately “
“highly,” or “extremely” bothering in their neighborhoods (Reference 13). in
the same study, people rated traffic noise situations in terms of both inten-
sity and frequency of annoyance. People annoyed by motorcycle noise rated the
intensity midway between “definitely annoying” and “strongly annoying.” The
only vehicle type receiving a higher annoyance intensity rating was buses. I
terms of frequency, motorcycles were reported as the source of annoyance
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
5-24
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proportion to actual numbers of motorcycles, as compared to other types of
traffic vehicles.
In one very applicable investigation, 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 (Reference 14). Listeners were
exposed to both constant speed cruises and accelerations. Figure 5—7 shows
the results of the subjective noise ratings of motorcycles as a function of
A-weighted noise level as heard by the listener. Ratings ranged from “quiet”
at 68.5 dB to “excessively noisy” at 96.5 dB. These results seem to compare
fairly well with those of another study In which ratings of single noise
events varied from “quiet” at 73 dB to “noisy (strongly)” at 92 dB (Reference
15).
A loud, short—duration vehicle passby may also Interrupt people’s activi-
ties, such as conversation, sleeping, TV viewing, reading etc. In a study of
the annoyance caused by different levels of simulated aircraft noise for
people seated indoors watching television, annoyance was found to be depen-
dent, at least in part, on speech interference (Reference 16). Not only
is the TV program, or other person speaking, more difficult to hear during the
time in which a noisy event is taking place, but it has been observed that the
distraction which may occur from the conversation in which the person is
engaged may contribute in itself to annoyance (References 16 and 17). The
speaker may attempt to cope with the noise Intrusion behaviorally, either by
increasing his or her vocal effort, or in more severe cases, by discontinuing
conversation altogether. Such behavioral reactions may be indicative of
general annoyance and disturbance with the intrusive noise event.
In general, interruptions of people’s activities lead to annoyance
(References 18 and 19), and represent a degradation of health and welfare.
For example, the reaction to a noise Intrusion during sleep Is, in many cases,
a change in sleep stage (from a “deeper” to a “lighter’ stage) or, if the
intrusive noise is intense or of prolonged duration, an actual awakening may
result. In either case, repeated disturbance of people’s sleep can be expect-
ed to adversely affect health and well-being.
Several investigations have shown that expressed annoyance with noise
correlates well with interference of activities due to noise (References 8,
20, 21, 22, 23, 24, and 25). One survey found that reports of interferences
with sleep and speech communication correlate more highly with feelings of
generalized annoyance than with any other factor, Including actual sound
levels measured outdoors (Reference 18).
For these reasons, the analysis of vehicle passby impacts were examined
in some detail to assess the significance of potential Individual event
exposures upon human activities (References 26 and 27), in particular, the
activities of speech comunication and sleep. The analysis was undertaken to
determine both the direct effect motorcycle noise may have on these activi-
ties, and to estimate the total potential annoyance attributable to motorcycle
noise. These single event pass—by noise Intrusions become particularly
Important in light of other regulations and efforts to reduce the noise from
other motor vehicles and urban noise sources. Namely, without a reduction In
noise emissions for motorcycles, the motorcycle will stand out as one of the
most, if not the most, intrusive noise sources.
5—25
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-96.5 dB
-87.2 dB
-82.5 dB
-77.8 dB
-63.5 dB
00
FIGURE 5-7. SUBJECTIVE NOISE RATING OF MOTORCYCLE SOUND LEVELS
source: reference 14
10
8
6
4
2
0
SOUND LEVEL (dB)
5-26
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5.6.1 Sleep Disturbance
The sleep periods of humans are typically classified into five stages.
In Stages I and II, sleep is light and the sleeper is easily awakened. Stages
III and rv are states of deep sleep where a person is not as easily awakened
by a given noise, but the sleep may shift to a lighter stage. An additional
stage, termed rapid eye movement (REM), 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
can cause impact (irritability, etc.) even though the sleeper may not awaken
(Reference 2).
A recent study (References 28 and 29) has summarized and analyzed sleep
disturbance data as gathered under experimental laboratory conditions. This
study demonstrated a relationship between frequency of response (disturbance
or awakening) and noise level, and further demonstrated that the duration of
the noise stimulus was a critical parameter in predicting response. The study
also showed that the frequency of sleep disruption is predicted by noise
exposure better than is arousal or behavioral awakening. An important fact is
that sleep disturbance is defined as any physiological change which occurs as
a result of a stimulus. The person undergoing such disturbance may be com-
pletely unaware of being afflicted; however, the disturbance may adversely
affect total sleep quality. This effect on overall sleep quality may lead to,
in certain situations, undesirable behavioral or physiological consequences
(Reference 2).
Data relating to the anticipated disruption of sleep caused by noise is
shown in Figure 5-8 (top). These data illustrate the frequency of sleep
disturbance (as measured by changes in sleep state, including behavioral
awakening) as a function of the sound exposure level (L 5 ) of the intruding
noise. The frequency of behavioral awakening as a function of sound exposure
level is also shown in Figure 5-8 (bottom). These relationships, adapted from
Figures 1 and 2 of Reference 28, consist of data derived from a review of most
of the recent experimental data on sleep and noise relationships. These
relationships show the approximate degree of expected impact (percent disrup-
tion or awakening) at given levels of noise. For example, in Figure 5-8, an
indoor sound exposure level of 60 dB would be expected to result in a 31
percent probability of a sleep disruption (change in depth of sleep). The
probability of being awakened is less than that of being disturbed. For this
example of a sound exposure level of 60 dB, the probability of being awakened
is 17 percent (see Figure 5—8).
Note also that the noise data contained in the references cited were
measured in terms of ‘ 4 effective perceived noise level” with a reference
duration of 0.5 seconds, LEPN (0.5 sec.). This level was converted to Ls by
the following approximate relationship*:
L 5 = LEpN (0.5 sec.) - 16 dB (13)
This equation accounts for the average difference of 13 dB between Per-
ceived Noise Level and A-weighted sound level, and the 3 dB that results
from the change in reference time from 0.5 seconds, used in Reference 28,
to 1 second, used in sound exposure level.
5—27
-------
z
0
I —
0
CO
a.
U i
LU
-J
C ’,
U-
0
>-
0
z
w
0
L U
U-
-.Jz
—
LLJ
cr
u-<
0- I
U i>
0I
U i
0
65 75 85 95 115
A-WEIGHTED SOUND EXPOSURE LEVEL
PROBABILITY OF A NOISE INDUCED AWAKENING
FIGURE 5-8 WEIGHTING FUNCTIONS FOR NOISE INDUCED SLEEP DISRUPTION AND
SLEEP AWAKENING
adapted from reference 28
60 70 80 90
A-WEIGHTED SOUND EXPOSURE LEVEL
PROBABILITY OF A NOISE INDUCED SLEEP STAGE CHANGE
0
45
55
105
5-28
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The impact weighting function scale for both disturbance and awakening
is defined such that a probability of 100 percent disturbance or awakening
has a Fractional Impact or weighting of 1.0, and a probability of zero percent
has a weighting of zero. The Level Weighted Population for sleep disturbance
and awakening was derived for each of the regulatory schedules and study years
under investigation by using Equations 10 and 11, substituting W(L 5 ) for
W(Ldn). The impact weighting function for these two situations is calculated
by using the following regression equations (from Figure 5-8):
W(L 5 ) = 0.0135 (L 5 - 37) for sleep disturbance, and (14)
W(L 5 ) 0.0110 (L 5 - 45) for sleep awakening. (15)
5.6.2 Speech Interference
As is the case with sleep disruption, speech interference occurs as a
result of individual noise events. The potential for speech interference
(i.e., the interruption of conversation) due to motorcycle noise occurs when
externally-propagating noise exceeds certain levels. However, unlike sleep
disruption, the impact of noise on speech interference is not cumulative.
That is, the duration of the noise event causing speech interference does not
affect the kind of interference, although it does, of course, affect the
duration of the interference. This is in contrast to sleep disturbance,
where the cumulative effect of noise can change the impact from one of sleep
disturbance to an actual sleep awakening. Therefore, the appropriate noise
metric for measuring speech interference potential is an Leq averaged over the
duration of the event, rather than a sound exposure level which specifically
considers the effect of the duration on the event.
Also, unlike sleep disruption, interference of speech may occur when
people are either indoors or outdoors. The degree of speech interference from
noise is dependent on the particular circumstances involved. Noise level and
duration, separation distance of the conversers, and vocal effort are all
factors that influence speech intelligibility (Reference 8). The criteria
showing degrees of outdoor and indoor speech interference from noise are shown
in Figures 5-9 and 5—10, respectively (Reference 8).
It should be recognized that the analysis does not assume that everyone
is talking all the time. The procedure instead assesses a potential for
speech interference and associated annoyance. Although the exact function of
the population that is engaged in conversation or listening activities at any
one instant is unknown, the actual relative benefits for speech interference
should be the same as the potential relative benefits calculated in these
analyses. Also, the relationships displayed in Figures 5-9 and 5-10 pertain
to sentences known to listeners. All listeners are further assumed to have
normal hearing. Under everyday environmental conditions, it would be expected
that communication intelligibility would be somewhat less than that portrayed
in Figures 5-9 and 5—10. For those people suffering some hearing loss,
background noise levels need to be up to 10 dB lower to attain the same degree
of intelligibility (Reference 30).
5-29
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100
>-
-J
-J
-J
w
I-
z
w
0
z
w
z
w
U)
U i
0
U i
0
FIGURE 5-9
80
60
40
20
050
LEVEL OF CONTINUOUS NOISE CAUSING INTERFERENCE (dB)
WEIGHTING FUNCTION FOR INDOOR SPEECH INTERFERENCE (RELAXED
CONVERSATION AT GREATER THAN 1 METER SEPARATION, 45 dB
BACKGROUND IN THE ABSENCE OF INTERFERING NOISE)
FROM REFERENCE 8
5-30
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LEVEL OF CONTINUOUS OUTDOOR NOISE CAI4S1NG
INTERFERENCE (Leq) dB
FiGURE 5-10
WEIGHTING FUNCTION FOR OUTDOOR SPEECH INTERFERENCE
(NORMAL VOICE AT 2 METERS)
FROM REFERENCE 8
>-
I —
-J
-J
-J
LU
I .-
z
z
w
0
LU
I-
z
LU
z
LU
C-)
LU
5-31
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People can have their conversations disrupted by externally propagated
motorcycle noise in at least three major settings during the day: as pedes-.
trians on the street, as residents inside their homes, or as residents
who are involved in activities just outside their homes. Three different
approaches are required to assess the impact of these three different situa-
tions. Each approach 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, but not along
the street.”
5.6.2.1 Indoor Speech Interference
Indoor speech interference is assumed to occur when motorcycle noise
propagates through walls of residences or buildings and peaks above a typical
indoor background level of 45 dB. The criteria of impact for indoor speech
interference is given in Figure 5-9. The curve is based on the reduction of
sentence intelligibility (sentences known to listeners) relative to the
intelligibility which would occur at 45 dB. For people conversing indoors
during the time of a vehicle passby, Figure 5-9 shows the probability of a
disruption in communication. The appropriate metric in Figure 5-9 is the
equivalent sound level over the duration of the event. The Level Weighted
Population for indoor speech interference is obtained by using equations io
and 11, substituting W(Leq(T)) for W(Ldn), and letting Pj represent the number
of people exposed at each indoor sound level for each passby.
5.6.2.2 Outdoor Speech Interference
The population exposed to potential outdoor speech communication inter-
ference are those people who are outside of their homes but not along a
street. This analysis does not take into account 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 or
engaged in other activities outdoors.
Outdoor speech interference due to the operation of motorcycles occurs
when the maximum noise level of the pass-by exceeds an outdoor background
level of 50 dEL For this analysis, 55 dB is used as the average Outdoor
background level. Although the outdoor background noise level in a number of
urban areas may today be greater than 55 dB, coordinated Federal, state, and
local efforts to reduce urban noise make the 55 dB level an appropriate value
to use on a national basis for future years (the primary focus of this pre-
dictive analysis).
The criterion for outdoor speech interference is shown in Figure 5-10 as
a function of the level of an interfering noise. Note that the appropriate
noise metric against which percent speech interference (unintelligibility of
sentences known to listeners) is plotted is an equivalent sound level Over
the duration of the pass-by. The Level Weighted Population for outdoor Speech
interference may be computed by using Figure 5-10 and equations 10 and 1
5.6.2.3 Pedestrian Speech Interference
Speech communication may be especially difficult for pedestrians who
are nearby roadway traffic. This is because pedestrians are typically located
5—32
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very close to the vehicles as they travel by. Pedestrian speech interference
is calculated by considering a percentage of the population to be pedestrians
located at the edge of clear zones associated with each roadway. Figure 5-10
and equations 10 and 11 are then used to evaluate the speech interference
impact upon pedestrians.
Again, it should be noted that the single event noise analysis examines
the effects of motorcycle noise alone, and hence does not take into account
the presence of other noise sources in the environment. It is obvious that
other environmental noise sources create background noise at such levels in
certain situations that motorcycle noise may be masked. This analysis only
represents the benefits accrued during those times when motorcycle noise
clearly intrudes over the ambient or background noise level. The ovc rall
absolute impact upon activities is, of course, dependent on the background
level assumed. However, the calculated benefits are representative of the
relative reduction in corrmunity impact of motorcycle noise over any given
ambient noise level.
5.7 Noise Prediction Model
The prediction model used in this health and welfare analysis is titled,
“The National Roadway Traffic Noise Exposure Model.” This predictive model is
a more sophisticated version of the original health and welfare model present-
ed in the “Proposed Motorcycle Noise Emission Regulation: Background Docu-
ment”. The National Roadway Traffic Noise Exposure Model was recently devel-
oped under EPA sponsorship, for the purpose of more accurately estimating
nationwide traffic noise impact. Its documentation is contained in a single
volume report (Reference 31) available from the Office of Noise Abatement and
Control, U.S. Environmental Protection Agency. Reference 31 explains the
methodology used by the computer model. The specific data contained in
Reference 31 does not necessarily represent the updated data gathered for the
motorcycle study (see Appendix N). The computer program itself is also
available from EPA.
In this subsection we present an overview of the National Roadway Traffic
Noise Exposure Model. Details of the model are presented in Appendix N,
though not to the same detail as in the documentation report (Reference
31). Appendix N contains information on the data, the calculations, and the
assumptions that underlie the model. Particular attention is given to those
details critical to the analysis of motorcycle noise emission regulatory
alternatives. The discussion in Appendix N covers defined inputs and basic
assumptions that underlie the computer predictions.
5.7.1 General Overview of the Model
The model consists of two parts: the General Adverse Response part and
the Single Event Response part. These two parts of the model appear side-by-
side in Figure 5—11, to emphasize their similarity.
Both parts of the model start with user—defined input, keyed as U in
the figure. For example, such input includes the potential emission imits
for newly manufactured motorcycles as they are typically operated. Both parts
of the model then mathematically combine this user—defined input with large
5-33
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GENERAL ADVERSE RESPONSE
PART
USER-DEFINED INPUT
DATA IN COMPUTER
PROPAGATION MATH
NOISE
AVERAGE OVER FULL YEAR
Ldfl
NATIONWIDE IMPACT
GENERAL ANNOYANCE
SINGLE EVENT RESPONSE
PART
USER-DEFINED INPUT
DATA IN COMPUTER
PROPAGATION MATH
NOISE
FOR TYPICAL 24 HOURS
Leq 1 AND Ls
NATIONWIDE IMPACT
POTENTIAL ACTIVITY
INTERFERENCE
1. AWAKENINGS
2. OTHER SLEEP DISRUPTIONS
3. SPEECH DISRUPTIONS
FIGURE 5—11.
THE NATIONAL ROADWAY TRAFFIC NOISE EXPOSURE MODEL
5-34
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quantities of additional data that reside within the computer program. These
additional data include noise emissions of other vehicles, as well as traffic
data, roadway configuration data, noise propagation data, and residential
population data.*
Both parts of the model then combine these data to predict the particular
noise levels of interest. The General Adverse Response part predicts the day-
night noise level, Ld , averaged over a full year . In a parallel manner, the
Single Event Response part predicts both Souiid Exposure Level, L and the
single-event Equivalent Sound Level, L (T)’ for each vehicle pas 5 sby on a
typical during the year. eq
As discussed previously, the yearly-average noise level correlates well
with noise—induced annoyance in and around the home -- that is, with a per-
son’s general adverse response. On the other hand, the noise from individual
vehicles, not averaged into the ambient noise background due to other sources,
often predicts additional impact due to particularly noisy or isolated single
events. These three noise descriptors -- Ldfl, L , and Le (1) -- were discussed
in detail Section 5.3. S q
As shown in the last module in Figure 5-11, the model converts the
computed noise levels into measures of estimated Impact. The General Adverse
Response part of the model estimates the extent to which people in the United
States will be highly annoyed by traffic noise experienced at or near their
homes. The Single Event part estimates the potential of a single noise source
(in this case motorcycles) to awaken people from sleep, to otherwise disrupt
their sleep, and to interfere with people’s speech at home, both indoors and
outdoors.
In suninary, the flow in Figure 5-11 progresses from user-defined input,
through the data and mathematics within the computer program, to the predicted
noise levels -— and then estimates potential noise impacts. The two parts
of the model estimate two different aspects of noise impact: yearly-average
and single-event. Both aspects are estimated nationwide.
5.7.2 Overview of the Noise Exposure Predictions: General Adverse Response
Figure 5-12 illustrates the manner in which noise predictions are made
for the National Roadway Traffic Noise Ex gsure Model, for General Adverse
Response. The figure is keyed through (. ) to coordinate with the detailed
discussions that follow.
This predicative procedure is best explained by starting with key
J which addresses the predicted noise exposure for Person #1. As shown In
Figure 5-12, noise exposures are also predicted for Person #2, Person #3, etc.
In essence, the model statistically predicts the noise for every person in the
United States -- a 1974 total population of 216.7 million persons, and rising.
W’flie remaiiiiler of the discussion will not generally distinguish between
user defined input and input data that resides within the program. See
Reference 31 for further details.
5-35
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=2#3
FIGURE 5—12. NOISE EXPOSURE PREDICTIONS:
GENERAL ADVERSE RESPONSE
* EL is the noise emission level . Each of the 5 speed ranges has a specific
EL associated within. Id1e mode has only one EL.
VEHICLE TYPE 1
OPMODE 1
#2 #3 #4
5 5 1
FRACTION TIME IN
THIS MODE
SPEEDS
EL
EL EL EL
EL
R OAD WAY 1
ETC
ETC
FRACTION OF MILEAGE AT EACH
SPEED
AVERAGE DAILY TRAFFIC
TRAFFIC MIX
LANE WID1H
NUMBER OF LANES
CLEAR-ZONE WIDTH
PROPAGATION
DISTANCE/GROUND EFFECTS
S 4IELDING
—
NOISE
PERSON
AVERAGE OVER
1
FULL YEAR
OUTDOOR Ldfl
ETC
=3
5-36
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Rather than predicting the noise exposure of each individual, the com-
puter groups people into homogeneous areas by city size and population den-
sity. Similar groupings occur throughout all blocks in Figure 5—12, though
they are not indicated. The concepts involved in the prediction model are
clearer without the details and approximations of grouping. These details
and approximations are postponed for now.
In essence, then, the model statistically predicts the traffic noise
environment experienced by everyone in the United States. The model also
takes into account population growth for future years.
The noise level at Person #1 emanates from all the roadways within his
hearing. (Key in Figure 5-12). Each roadwayiTso has specified as input
its average daily traffic and its average mix of vehicle types. Each roadway
also has associated with it a large range of typical vehicle speeds. Although
vehicle speeds vary on each roadway from moment to moment, the program con-
siders their average speed for any given mile of roadway. The fractions of
the total roadway mileage at each of five speed ranges are specific input used
within the computer program, for each roadway.
In addition, each roadway has a specific lane width, a specific number of
lanes, and a specific clear-zone width. The latter is generally the right-of—
way width. It encloses the region within which no one lives.
Roadway noise, close by the roadway, is dependent upon vehicle speed,
average daily traffic, traffic mix, lane width, number of lanes, and clear
zone width. As this noise propagates outwards from the roadway to the person
of interest, it is influenced by a number of propagation parameters. Two
principal parameters are the distance between the person and the roadway,
and the shielding that intervenes between the person and the roadway. These
two parameters are specified for each person/roadway pair —— in groupings, as
mentioned above.
From Key to Key J the noise level at each person’s residence
depends upon the source strength of each roadway, and upon the propagation of
the noise from the roadway.
In addition to the above parameters, roadway source strength also
depends, in part, on a numb.er of other factors. As noted in Key each
roadway contains a series of vehicle types. Each vehicle type operates in
four modes, numbered in Figure 5—12. These modes are: acceleration, de eler-
ation, cruise and idle. Each vehicle spends a definite fraction of its time
in each of the four modes. These fractions are specified for each operating
mode and separately for each vehicle type. Then each mode fraction is split
into the five speed fractions specific to that roadway (Key again).
The final entries at Key are the noise emission levels. These
differ for each of the four operating modes, and for each of the five speeds.
These emission levels are a user—defined input, and are keyed therefore as
j J in the Figure. Specifically, the user defines the noise emission levels
for new vehicle sales in any given year. Then the computer adds those vehi-
cles to the ones already on the road, and depletes the general population of
vehicles by those vehicles that retire from service.
5-37
-------
The noise emission values put into the model constitute the mechanism
by which we can investigate consequences (impacts) of a potential vehicle
noise emission regulation. The model is applied for successive years, as
more and more of the quieter vehicles are introduced into service. The
year—to-year effect on predicted noise impact is a direct measure of the
effectiveness of a regulation. (Figure 5-12 does not indicate this year—to
year appi icat ion.)
In practice, then, Figure 5-12 flows from top to bottom. For the regu...
lated vehicle type, emission levels corresponding to the regulatory levels
are entered, separately for the four operating modes and separately for the
five speed ranges within each operating mode (except idle). As shown i,,
Figure 5-12, sixteen values of emission level are entered for each vehicle
type.
These emissions are combined with the fractions of time spent by that
vehicle type in each mode/speed, to obtain that vehicle’s contribution to
the traffic noise. The computer carries out these calculations for each
vehicle type on that roadway. Then all vehicles are combined for Roadway #1,
according to the average daily traffic and vehicle mix.
This process is repeated for each roadway type.
Each roadway’s noise is then propagated to each person’s residence.
At each residence the noise levels from all roadways are combined into one
total noise level.
This entire process is repeated for all persons in the United States
(approximated by residential population density information), as shown to the
right at Key in Figure 5-12.
5.7.3 Overview of the Noise Exposure Predictions: Single Event Response
Figure 5—13 illustrates the noise prediction flow chart for the Single
Event Response portion of the model. Differences between Figure 5-12 and
Figure 5—13 are few, but important. Figure 5—13 examines only one vehicle
type or class at a time, since only its passby noise is assessed.
Key data requirements are identical to the General Adverse Response
portion of the model.
At Key 0 , only the average daily traffic for that vehicle type is
required, rather than the full traffic and vehicle mix. Also at Key c
building noise isolation values are needed to propagate the noise from out
doors to indoors. These building noise isolation values are specified inputs.
The major differences between the Single Event and General Adverse
Response portions of the model occur at Key . For each person, the
single-event equivalent sound level, Leq(T), is computed for indoors, both day
and night, and for outdoors, day only. These predictions then apply to the
fraction of time the average person is at home day/night and indoors/outdoors
In addition, the sound exposure level, L 5 , is computed for indoors, both day
and night -- and then applied to the fraction of time that person is asleep,
either day or night.
Key summarizes the types of noise calculations made.
5-38
-------
=3
ETC
—
P
ETC
FIGURE 5—13.
NOISE EXPOSURE PREDICTIONS:
SINGLE EVENT RESPONSE
0
VEHICLE
TYPE
OPMODEff1
#2
#3
#4
FRACTION TIME IN
THIS MODE
5
5
1
SPDS
EL.
EL EL EL
EL
ROAD WAY
FRACTION OF MILEAGE
EACH SPEED
VEH #1 AVERAGE DAILY
TRAFFIC
LANE WIDTH
NUMBER OF LANES
CLEAR-ZONE WIDTH
PROPAGATION
DISTANCE/GROUND EFFECTS
SHIELDING
BUILDING ISOLATION
PERSON
=1
NOISE
FOR TYPICAL 24 HOURS,
EACH PASSBY’S
FRACTION OF TIME AT
HOME AND
P
t3
INDOORS
OUTDOORS
INDOORS
OUTDOORS
DAY AND
DAY
NOT
NIGHT
Leq(T)
L (TI
ASLEEP
NDOORS
DAY AND
NIGHT
ETC
INDOORS
ASLEEP
5-39
-------
5.7.4 Overview of Noise Impact Estimates: General Adverse Response
The flow chart for noise impact estimates of the General Adverse Response
portion of National Roadway Traffic Noise Exposure Model is presented in
Figure 5—14. The Figure is keyed J through ® , to coordinate with the
more detailed discussions that are presented in Appendix N.
The top set of modules, Key , duplicates the bottom set in Figure
5-12. It consists of afl the person/noise pairs for the entire United States,
as predicted by the model.
At Key , this very large set of person/noise pairs is sorted by noise
level. For example, all the persons in the U.S. exposed to an outdoor Ldn of
55 dB are grouped together in this sorting process. The next set of boxes
(top of Key ) results.
The top of each module in Key contains all the persons exposed to
that particular noise level. Noise impact is calculated by multiplying the
number of people exposed at each noise level by the fractions next shown in
the Figure (middle of Key ). These are the fractional weighting values
used to represent the number of people expected to be highly annoyed by that
particular noise level. (See section 5.5 for an explanation of the fractional
weighting values.) These fractions are essentially zero at 55 dB, and
increase to nearly unity around 75 dB.
To complete the mathematics at Key , the number of people exposed
times the appropriate fraction or weighting equals the Level Weighted Popula-
tion (LWP) for General Adverse Response (equation 10) for each noise exposure
band. For example, if 28,000 people are exposed to an Ldn of 60 dB, then this
number of people, times the fraction 0.25, yields an LWP of 7,000. This
number shows that not everyone is impacted to the same degree Primarily
because some may be less susceptible to noise intrusion. These fractions
summarize, therefore, the variability among all persons in their reactions to
the same noise level.
As the final step in the impact estimate (Key ®) the expected impacts
at each exposure level are added to obtain the total expected impact in the
United States (equation 11). The resulting number is the total Level Weighted
Population (LWP). It combines population and noise level information into a
single impact value.
Also at Key c in Figure 5—14 are the impact estimates for the remain..
der of the 40-year time stream. As an increasing number of quieter vehicles
are introduced into service, the estimated impact should drop. The change in
this impact from year-to-year is a direct measure of the regulation’s benefit.
To rerun the program for subsequent years, additional noise emission
values must be entered. The computer will then add these quieter vehicles to
the ones already on the road, and will deplete the general population of
vehicles by those vehicles that retire from service. These sales and deple_.
tion rates reside in the computer. In addition, the model also accounts for
changes in United States population each year.
5-40
-------
NOISE
ETC
NA9IONWIDE IMPACT 1974
LEVEL WEIGHTED POPULATION
1975 2013
FIGURE 5-14. NOISE IMPACT ESTIMATES: GENERAL ADVERSE RESPONSE
5-41
-------
5.7.5 Overview of Noise Impact Estimates: Single Event Response
Figure 5-15 illustrates the logic flow that provides impact estimates for
the Single Event Response portion of the model. Differences between Figure
5-14 and Figure 5—15 are minor. Here, each person is exposed not just to one
noise level, but to a series of single-event noise levels that occur over a
typical 24 hour period. In other words, each person is paired with many
noise levels, each redicted as described earlier. After sorting, then, the
tabulation of Key (. ) is not of persons, but is of noise events. A single
person will be exposed to many noise events, all sorted by noise level.
The fractions in Key J are the fractions (or probability) of these
single events that are expected to actually impact the person who is exposed.
The measures used represent the potential to awaken people from sleep, or
otherwise to disrupt sleep, or to interfere with one’s speech coninunications.
(See Section 5.6 for an explanation of the fractions.)
Each of these distinct types of single—event impacts is estimated
separately.
5.7.6 Data Groups
As mentioned earlier, the computer program groups much of its data.
Such grouping occurs throughout all modules in Figures 5-12 and 5—13, though
grouping is not indicated in either figure.
The grouping of data within the model appear in Table 5-6, for:
• 14 vehicle types
• 4 operating modes
• 5 speed ranges
• 6 roadway types
9 population groups
• 4 population/density groups
33 population/density “cells”
• 40 years of the time stream
Vehicle types were grouped based on those groups used for all EPA studies
of roadway noise. The groupings are strongly suggested by similarity in
noise emission within a type, due to similarity in engineering or Operational
characteristics.
Operating modes are based upon extensive vehicle noise tests and appro-
priate data reduction methods (References 32, 33, and 34). Speed ranges are
based upon these same tests.
Roadway types are the functional categories defined by the Federal
Highway Administration (Reference 35).
Population groups are based on the data base assembled by the Federal
Highway Administration (References 35, 36, and 37), and were refined usin9
1970 census data (Reference 38). Population density groups were also based
upon these same Federal Highway Administration and census publications
5-42
-------
NOISE NOISE
P p
=2 =3
Leq Leq L q L q
CT) CT) CT) CT)
SORT BY
SINGLE-EVENT
NOISE LEVELS
/
55dB 56 57
NUMBER OF EXPOSURES
POTENTIAL FRACTION OF•
PEOPLE IMPACTED BY EACH
EXPOSURE
POTENTIAL NUMBER
OF IMPACTS
FIGURE 5—15.
1975
NOISE IMPACT ESTIMATES: SINGLE EVENT RESPONSE
ETC
0
ETC
NATIONWWDE IMPACT 1974
POTENTIAL ACTIVITY INTERFERENCE
1. SLEEP AWAKENING
2. OTHER SLEEP DISRUPTION
3. SPEECH INTERRUPTION:
• INDOORS AT HOME
• OUTDOORS AT HOME
• PEDESTRIANS
2013
.• S
5-43
-------
TABLE 5-6. DATA GI JUPS WIThIN ThE ‘DDEL
PARAMETER G1 JtJP VWE TYPE DESCRIPTION
Vehicle Car/B/automatic Passenger car, 8 cylinder, gas,
Types automatic
Car/6/automatic Passenger car, 6 cylinder, gas
automatic
Car/manual Passenger car, 6 or 8 cylinder,
gas, manual
Car—LT/auto Passenger car and light truck,
4 cylinder, gas, automatic
Car—LT/inanual Passenger car and light truck,
4 cylinder, gas, manual
LT Light truck, 6 and 8 cylinder, gas
Car—LT/diesel Passenger car and light truck,
diesel
Medium truck, two axle
(GVWR 10,000 ib)
Heavy truck, three or nore axles
(GVWR 26,000 ib)
Intercity bus Intercity bus
Transit bus Transit bus
School bus School bus
Unriod MC UfliTodi f ied rrotorcycle
Mod MC Modified itotorcycle
Operating
Acceleration
Acceleration from zero to
speed S
Modes
Deceleration
Cruise
Idle
Deceleration from speed
Cruise at speed S
Idle
S
to zero
Speed
20 mph
Less than 25 mph
Ranges
30 mph
40 mph
50 mph
60 mph
Between 25 and 35 mph
Between 35 and 45 mph
Between 45 and 55 mph
More than 55 mph
Roadway
Interstate
Per FHWA definition
Types
Highways
Freeways and
Expressways
Major Arterials
Minor Arterials
Collectors
Local Roads and
Streets
Per FHWA definition
Per FHWA definition
Per FHWA definition
Per FHWA definition
Per FHWA definition
Population
Population over
2M
Groups
1M to 2M
500K to lM
200K to 500K
lOOK to 200K
50K to lOOK
25K to 50K
5K to 25K
Rural areas
r A l
-------
Table 5—6. (continued)
PARAMETER
GROUP_NAME
TYPE_DESCRIPTION
Population
Density
1.
High
‘bre than 4,499 people per
square mile
Groups
2.
3.
4.
Medium-to--High
L —to—Medium
Low
3,000 to 4,499 people per
square mile
1,500 to 2,999 people per
square mile
Less than 1,500 people per
square mile
Pop/density
“cells”
1
2
3
4
Population over 2M, high density
Sane, medium-to-high density
Sane, low—to-medium density
Sane, low density
5
6
7
8
1M to 2M, high density
Same, medium-to-high density
Same, low-to-medium density
Sane, low density
9
10
11
12
500K to 1M, high density
Sane, medium-to-high density
Sane, low—to-medium density
Same, low density
...
29
30
33.
32
5K to 25K, high density
Same, medium-to-high density
Sane, low-to--medium density
Sane, low density
33
Rural, low density only
Years 1974 For prediction of future iitpact
1975
1976
1977
.
.
2013
5—45
-------
These two latter groups are then combined into pop/density cells” shown
next in Table 5-6. Thirty-three of these pop/density hlcelisu result, since
the rural population group is paired with only the low—density group. These
pop/density °cells” contain among them the entire U.S. population and also the
entire U.S. roadway mileage. They therefore provide the structure for match
ing each person in the United States with the roadways that produce the noise
at his residence.
Lastly, Table 5-6 shows that calculations are performed for all years
within a 40-year time stream. A baseline year is selected.* For that year,
all data (such as traffic counts, roadway mileage, population densities)
are explicitly put into the computer program. Then for future years, these
data are factored upward, if appropriate, to account for growth.
The data groups within Table 5-6 interrelate within the model in complex
ways as discussed in the more detailed descriptions contained in Appendix N.
5.8 Results of Analysis - Street Motorcycles
As discussed in sections 5.5 and 5.6, results of the impact analysis for
motorcycles center around two measures: (1) the Level Weighted Population,
LWP, and (2) the Relative Change in Impact, RCI. LWP is an index which repre....
sents the total number of persons in the United States Wno are impacted by
roadway noise during any given year of interest and the degree or severity of
that impact upon each person. The RCI values represent the percentage change
in LWP due to regulation relative to a baseline condition. A decrease in LWP
results in a positive RCI -- that is, a benefit in terms of a percentage
reduction in extent and severity of impact.
For this analysis RCI is calculated for each regulatory option using two
different approaches. The first approach calculates the percentage change lfl
LWP for a specific future year relative to the baseline condition in the yea,-
1980. The results are tabulated as RCI” (without an asterisk). Thus, RCj
describes projected benefits relative to current day (1980) conditions. For
example, an RCI of 25 percent in 1995 means that, in 1995, the adverse impact
will be 25 percent less than it was in 1980 with no regulation in effect
Similarly, an RCI of negative 15 percent in 1995 means that the adverse impact
has increased by 15 percent relative to 1980. These values of RCI include the
effects of all changes between 1980 and the specified year in the future
That is, these RCI values reflect the impact of the motorcycle noise emissjoi
regulation and the influence of such factors as increased traffic volume
noise regulation of other vehicles, increases in the number of motorcycles an.
increases in the growth of the U.S. population.
The second approach calculates the percentage change in LWP for a sped...
fied future year relative to the same future year without a motorcycle regu1 _
tion. These values of RCI are labeled as URCI*H (with an asterisk). For a
given year of interest, the RCI* values reflect the benefits attributable to
For this ä1ysis , much of the data was entered for 1974. These data
were applied to later years after suitably adjusting for growth.
5-46
-------
the motorcycle noise regulation alone -— that is, benefits that will occur
relative to that specific year if there were no motorcycle regulation. For
example, an RCI* of 40 percent in 1995 is interpreted as a reduction in impact
of 40 percent in 1995 from that which would occur in 1995 with no regulation.
In brief,
° RCI compares the impact ‘in the year—of—interest (with regulation)
to the impact in the year 1980, during which there is no regula-
tion, less traffic, fewer motorcycle operations and a lower popu-
1 at i on.
° RCI compares the impact in the year-of-interest (with regulation)
to the same year, without regulation.
The RCI and RCI* values are considered to be more accurate predictors
of actual benefits to be realized than the LWP values reported. This is
because the RCI and the RCI* involve changes from a baseline condition. In
the computation of RCI and RCI*, inaccuracies in baseline LWP tend to be
cancelled out by the same inaccuracies in the year-of—interest LWP.
With these indices of noise impact —- LWP, RCI and RCI* -- two distinct
types of impact are assessed: (1) General Adverse Response, based upon Ldn,
and (2) Single Event Activity Interference, based upon LS for sleep inter-
ference and upon Leq(T) for speech interference. In the discussions that
follow, these two types of impact are addressed separately. For each, the
results are tabulated for a series of future years (through the year 2010),
and for a series of possible regulatory options (Table 5-1). Option Q repre-
sents the maximum benefits achievable and can be used as an upper limit guide.
5.8.1 General Adverse Response
The General Adverse Response portion of the model assesses the impact
from the motorcycle noise emission regulation on a national aggregate basis.
It does not assess the reduction in terms of specific localized street condi-
tions which under some circumstances may show substantially greater relative
benefits than indicated within this analysis.
The general adverse response impact estimates are presented in Tables
5-7 to 5-9. For each table, a different proportion of modified motorcycles
(12, 7 and 3 percent) is considered (see Section 5.2.1.1). In each table the
Level Weighted Population (LWP) and the Relative Change in Impact (RCI and
RCI*) are shown for four years (1980, 1990, 2000, and 2010) in the regulatory
time stream for motorcycles. In these tables, the baseline (no regulation)
option is listed as Option 1. Also, the RCI and RCI* values in these tables
are calculated relative to the condition of 12 percent modified motorcycles
since this represents the current (1980) estimate of the proportion of
modified motorcycles. Thus the impact and benefit estimates found in Tables
5-8 and 5-9 (with 7 and 3 percent modified motorcycles, respectively) repre-
sent changes in impact attributable to both lessened noise emissions and
reduced number of modified vehicles. For example, in Table 5-8 (7 percent
5-47
-------
TABLE 5-7
General Adverse Response Impact with 12 percent
Modified Motorcycles’
1981 f99o
LWP 2 Rd 3 RCI* 3 LWP 2 Rd 3 RCI* 3 LWP 2 Rd 3 RCI* 3 LWP 2 RCI 3 RCI* 3
Regulatory
Option
2000
u1o
Option 1
29.4
0.00
0.00
31.6
-7.56 0.00
38.6
-31.47
0.00
47.5
61.82
0.00
Option 2
-
-
-
-
31.4
-7.05 0.47
38.4
-30.79
0.52
47.3
-61.07
0.46
ption 3
—
-
31.1
-5.82 1.61
37.9
-28.99
1.89
46.7
-59.09
1.68
Option 4
— -
-
- —
-
31.1
-5.89 1.55
37.9
-28.99
1.89
-
46.7
-59.09
1.68
Option 5
-
30.9
-5.21 2.18
37.5
-27.79
2.80
46.3
-57.772.50
Option 6
-
31.0 —5.65 1.77
30.9 —5.28 2.12
37.5
—27.79
2.80
46.3
—57.77
2.50
U,
. .
Option 7
—
—
-
37.5
-27.79
2.80
46.3
-57.77
2.50
.
—----__
Option 8
- -
-
31.0
-5.721.71
37.5
-27.79
?.80
46.3.
-57.77
2.50
Option 9
-
-
-
30.9
—5.21 2.18
37.1
-26.43
3.83
45.9
-56.30
3.41
Option 10
-
-
-
31.0
-5.72 1.71
37.2
-26.74
3.60
45.9
-56.30
3.41
Option Q
-
-
-
30.4
-3.58 3.70
37.0
-26.02
4.15
45.8
-55.86
3.68
NOTES:
1 In order to estimate the general adverse response impact of motorcycles in the traffic stream, the following
assumptions were made regarding other vehicles:
(a) Light vehicles are unregulated
(b) Trucks are regulated as promulgated: 83 dB in 1978, 80 dB in 1982.
Cc) Buses are regulated as follows: 83 dB in 1981, 80 dB in 1985, 77 dB in 1987.
2
LWP = Level Weighted Population (millions)
The relative changes in impact (RCI and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
-------
In order to estimate the general adverse response impact of motorcycles in the traffic stream,
the following assumptions were made regarding other vehicles:
(a) Light vehicles are unregulated
(b) Trucks are regulated as pronlulgated: 83 dB in 1978, 80 dB in 1982.
(c) Buses are regulated as follows: 83 dB in 1981, 80 dB in 1985, 77 dB in 1987.
LWP = Level Weighted Population (millions)
The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle
regulation, with 12 percent of the motorcycle population modified since this represents the
current estimate of modified motorcycles.
These numbers are given to show the change in LWP due to a reduction in the number of
modified motorcycles without concurrent reductions in the sound levels of new motorcycles.
TABLE 5-8
General Adverse Response Impact with 7 percent
Modified Motorcycles’
s. D
1981
1990
2000
2010
Regulatory
Option
1wP 2 Rd 3
RCI* 3
LWP 2
Rd 3
--
RCI* 3 LWP 2
Rd 3
RCI* 3
LWP 2
Rd 3
RCI* 3
Option 1
28.4k 3.30
3.30
29.$
—1.70
5.45 36.3
—23.60
5.98
44.8
-52.49
5.77
Option 2
— -
-
29.7
—1.19
5.92 36.1
—22.92
6.50
44.6
-51.74
6.23
Option 3
- -
29.4
0.03
7.06 35.6
-21.08
7.90
44.0
-49.76
7.45
Option 4
-
-
29.4
-0.03
7.00 35.6
-21.08
7.90
44.0
-49.76
7.45
Option 5
- —
-
29.2
0.51
7.50 35.3
—20.10
8.65
43.6
-48.64
8.15
Option 6
-
—
29.3
0.17
7.19 35.3
-20.10
8.65
43.6
-48.64
8.15
ption 7
— -
-
29.2
0.44
7.44 _35.3
-20.10
8.65
43.6
-48.64
8.15
Option 8
— —
—
29.3
0.10
7.12 35.3
-20.10
8.65
43.6
-48.64
8.15
Option 9
— —
—
29.2
0.51
7.50 35.0
—19.04
9 46
43.3
-47.51
8.84
Option 10
- —
—
29.3
0.10
7.12 35.0
-19.28
9.27
43.3
-47.51
8.84
Option Q
- —
-
28.8
1.87
8.77 34.8
-18.60
9.79
43.2
-47.04
9.13
NOTES:
-------
TABLE 5-9
1
RCI* 3 LWP 2 Rd 3 RCI* 3 LWP 2
In order to estimate the general adverse response impact of motorcycles in the traffic
stream, the following assumptions were made regarding other vehicles:
(a) Light vehicles are unregulated
(b) Trucks are regulated as promulgated: 83 dB in 1978, 80 dB in 1982.
(c) Buses are regulated as follows: 83 dB in 1981, 80 dB in 1985,. 77 dB in 1987.
2
LWP = Level Weighted Population (millions)
The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle
regulation, with 12 percent of the motorcycle population modified since this represents the
current estimate of modified motorcycles.
4
These numbers are given to show the change in LWI’ due to a reduction in the number of
modified motorcycles without concurrent reductions in the sound levels of new motorcycles.
Regulatory
Option
I 9U1
LWP 2 RCI 3
General Adverse Response Impact with 3 percent
Modified Motorcycles 1
1990
uuu
RC i
2010
RCI* 3 LWP 2 Rd 3 RCI* 3
(-n
Option 1
27 . 9 k
4.97
28.9
1.67
3494 -18.97
9.51
43•34 -47.48
8.86
Option_2
-
-
-
28.7
2.18
9.06 34.7 -18.26__10.05
43.1 -46.70
42.5 —44.72
9.35
10.57
Option 3
-
—
-
28.4
3.41
10.20 34.2 —16.42
11.45
Option 4
-
-
-
28.4
3.34
10.13 34.2 -.16.42
11.45
42.5
-44.72
10.57
-
42.2 -43.80
11.13
çption 5
-
-
-
28.2
3.81
10.58 33.9 -15.60
12.07
Option 6
—
—
—
28.3
3.51
10.29 33.9 —15.60
12.07
42.2 —43.80
11.13
Option 7
—
—
—
28.3
3.75
10.51 33.9 —15.60
12.07
42.2 —43.80
11.13
Option 8
—
—
—
28.4
3.44
10.23 33.9 —15.60
12.07
42.2 —43.80
11.13
Option 9
—
—
—
28.2
3.81
10.58 33.7 -14.82
12.67
42.0 —42.92
11.68
Option 10
—
—
-
28.4
3.44
10.23 33.8 —14.99
12.54
42.0 —42.92
11.68
Option Q
—
—
-
27.9
4.94
11.62 33.6 -14.34
13.03
41.8 —42.44
11.98
NOTES:
-------
modified motorcycles), Option 5 in the year 2000 shows an RN of -20.10
percent relative to 1980 with no regulation and 12 percent modified vehicles.
Similarly, Option 5 in the year 2000 with 7 percent modified shows an RCI* of
8.65 percent relative to the year 2000 with no regulation and 12 percent
modified vehicles.
It may first be noted from Tables 5-7 to 5—9 that the LWP increases and
the RCI values become negative in future years even as more stringent regula-
tions are imposed. This increase impact means that the projected benefits
from reducing motorcycle noise emissions are expected to be overpowered by the
anticipated increase in vehicular traffic as well as population growth in the
United States between 1980 and the year 2010.
Also, Tables 5-7 to 5-9 shows that in terms of overall traffic noise
impact, the regulation of motorcycles results in a moderate overall reduction
in traffic noise impact due to the small motorcycle population and the domin-
ance of trucks arid automobiles in the overall traffic stream. It must be
reemphasized that these estimates are for impact on nationwide aggregate
basis. Such aggregate reductions on a national basis do not effectively point
up the potentially significant benefits that would occur in the urban environ-
nent for situations where there is a high volume of motorcycles.
From Table 5-7 (with 12 percent modified motorcycles) it may be seen that
benefits in terms of RCI* are predicted to range iro;i to four percent
depending upon the regulatory option. The benefits shown in this table are
those that would be experienced without a concurrent reduction in the number
of modified motorcycles. With the exception of Option Q, Options 9 and 10
show the greatest benefits, and Options 1 and 2 the least. Options 5, 7 and 9
would demonstrate benefits earlier than the others. Tables 5-8 (7 percent
modified) and 5-9 (3 percent modified) demonstrate similar trends with RCI*
benefits reaching to over 9 and 12 percent, respectively. These benefits
shown in Tables 5-8 and 5-9 are higher than those shown in Table 5-7 due to
the reductions in the number of modified vehicles.
Benefits of reducing the number of modified motorcycles without con-
current noise reduction of newly manufactured motorcycles can be seen by
comparing Option 1 (no regulation) across the tables. For example, reducing
the proportion of modified motorcycles from 12 to 3 percent is found to yield
an 8.86 percent benefit in the year 2010 in terms of reduction of overall
traffic noise impact.
In Tables 5-7 to 5-9, the total United States impact is collapsed into a
single—value LWP - for a given year and a given regulatory option. In this
condensation, the numbers of persons exposed to different noise levels is
lost. This population exposure information is presented in Tables 5-10
through 5—20. These tables show the number of persons in the United States
who live in specific noise exposure areas, due to traffic noise, in 3-decibel
ranges. Each table presents population exposure data for a separate regula-
tory option for 12, 7, and 3 percent modified motorcycles (see Section
5.2.1.1), with Option 1 again representing the case of no noise emission
regulation. As an example to assist in interpretation of this table, under
Option 1 (Table 5-10), in the year 2000 with 12 percent modified motorc..ycles,
5-51
-------
it is predicted that 128,670,000 people will be exposed to traffic noise at
levels exceeding an Ldn of 55 dB, and 7,400,000 people will be exposed to
levels greater than an Ldn of 70 dB. Likewise, under Option 7 (Table 6—16),
in the year 2000 with an assumed 7 percent modified motorcycles, it is
expected that 116,300,000 people would be exposed to traffic noise at an Ldn
of 55 dB or above, and 6,900,000 people above an Ldn of 70 dB.
It may be noted that the trends of Tables 5-10 through 5-20 follow
closely those of Tables 5—7 to 5—9. With the exception of ideali2ed Option Q,
Options 9 and 10 show the most benefits, with those of Option 9 occurring
somewhat earlier. Options 1 and 2 show the least benefit. The tables also
show that population exposure will increase over time despite the regulation
of motorcycle noise emissions. This is due primarily to growth in the number
of motorcycles and growth in the U. S. population. Again, substantial bene-
fits are shown as the number of modified motorcycles is decreased from 12 to 3
percent.
5.8.2 Single Event Activity Interference
The purpose of the single event activity interference analysis is to
examine the benefits of reducing motorcycle noise in greater detail. Here,
potential activity interference is examined separately for (1) sleep disrup-
tion, (2) sleep awakening, and (3) speech interference, both indoors and
outdoors, and pedestrian.
The single event impact estimates for motorcycles are presented for
each regulatory option outlined in Table 5-1. Summary tables (organized
identically to Tables 5-7 through 5-9 displayed previously) are presented for
each of the single event impact measurements.
o Sleep Disruption (Tables 5-21 to 5-23)
o Sleep Awakening (Tables 5-24 to 5-26)
o Indoor Speech Interference (Tables 5-27 to 5-29)
o Outdoor Speech Interference (Tables 5-30 to 5-32)
o Pedestrian Speech Interference (Tables 5—33 to 5-35)
The tabulated results are presented in terms of LWP, RCI, and RCJ*
for four years (1980, 1990, 2000, and 2010) in the regulatory time stream.
The results are also presented for the different assumptions of 12, 7 and
3 percent of the vehicles modified. In these tables, the baseline (no regu...
lation) option is listed as Option 1. Also, the RCI and RCI* values are
calculated relative to the condition of 12 percent modified motorcycles since
this represents the current (1980) estimate of the proportion of modified
motorcycles.
For sleep disruption, the Level Weighted Population (LWP) and both types
of Relative Change in Impact (RCI and RCI*) appear in Tables 5-21 through
5-23. These tables show very large benefits in. terms of a reduced potential
5-52
-------
TABLE 5-10: POPULATION EXPOSED ABOVE Ldfl = dB — OPTION 1
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
% Modified YEAR
MILLIONS
OF PEOPLE
12% 1981
0.00
0.00
0.00
0.20
0.58
1.54 3.43
6.53 11.19
16.28
23.68
31.50
94.94
1990
0.00
0.00
0.01
0.20
0.60
1.52 3.39
6.65 11.55
18.02
27.65
37.23
106.83
2000
0.00
0.00
0.03
0.30
0.81
2.02 4.24
8.10 13.85
21.67
33.84
43.81
128.67
2010
0.00
0.00
0.07
0.45
1.13
2.72 5.51
10.08 16.77
26.07
40.71
50.04
153.58
7% 1981
0.00
0.00
0.00
0.19
0.57
1.51 3.36
6.43 10.98
15.80
22.20
29.36
90.39
1990
0.00
0.00
0.00
0.19
0.58
1.46 3.27
6.41 11.12
17.01
25.33
34.24
99.61
2000
0.00
0.00
0.03
0.29
0.78
1.93 4.07
7.76 13.26
20.16
30.73
40.84
119.85
2010
0.00
0.00
0.08
0.43
1.09
2.62 5.30
9.71 16.08
24.09
37.05
47.27
143.73
3% 1981
0.00
0.00
0.00
0.19
0.56
1.48 3.31
6.33 10.82
15.59
21.69
28.64
88.61
1990
0.00
0.00
0.00
0.18
0.56
1.41 3.17
6.21 10.80
16.52
24.26
32.93
96.04
2000
0.00
0.00
0.03
0.27
0.76
1.86 3.93
7.49 12.84
19.42
29.31
29.27
115.17
2101
0.00
0.00
0.07
0.42
1.06
2.54 5.13
9.42 15.66
23.24
35.48
46.00
139.02
-------
TABLE 5—11: POPULATION EXPOSED ABOVE Ldn = 55 dB - OPTION 2
dB
RANGE
91.
88T
88.
85.
85.
82T
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67T 64T
64.
o1T
61.
58.
58.
55.
TOTAL
S
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
-
-
-
-
-
-
- -
-
-
-
1990
2000
2010
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.03
0.09
0.20
0.30
0.45
0.60
0.81
1.12
1.51
2.01
2.71
3.37
4.22
5.49
6.63 11.50
8.05 13.79
10.04 16.71
17.94
21.55
25.94
27.49
33.64
40.50
37.08
43.65
49.92
106.33
128.06
152.95
7%
1981
-
-
-
-
-
-
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.58
1.45
3.25
6.38 11.07
16.93
25.18
34.05
99.08
2000
0.00
0.00
0.03
0.29
0.78
1.92
4.05
7.72 13.20
20.05
30.52
40.61
119.16
2010
0.00
0.00
0.08
0.43
1.08
2.61
5.28
9.67 16.01
23.97
36.82
47.08
143.03
3%
1981
.
-
-
-
-
-
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.18
0.56
1.40
3.15
6.18 10.75
16.45
24.10
32.73
95.50
2000
0.00
0.00
0.02
0.27
0.75
1.85
3.91
7.44 12.77
19.31
29.08
39.02
114.43
2101
0.00
0.00
0.07
0.42
1.05
2.53
5.10
9.37 15.59
23.11
35.23
45.79
138.28
-------
TABLE 5—12: POPULATION EXPOSED ABOVE Ldn 55 dB - OPTION 3
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
%
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.01
0.20
0.59
1.49 3.34
6.55 11.38
17.74
27.11
36.67
105.07
2000
0.00
0.00
0.03
0.30
0.80
1.98 4.16
7.95 13.63
21.23
33.11
43.22
126.40
2010
0.00
0.00
0.09
0.44
1.11
2.68 5.42
9.92 16.53
25.58
39.91
49.56
151.24
7%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.57
1.43 3.21
6.31 10.96
16.75
24.79
33.58
97.79
2000
0.00
0.00
0.03
0.28
0.77
1.89 3.99
7.61 13.03
19.76
29.98
40.01
117.34
2010
0.00
0.00
0.08
0.43
1.07
2.58 5.21
9.55 15.85
23.63
36.20
46.59
141.19
3%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.17
0.56
1.38 3.12
6.10 10.63
16.28
23.71
32.24
94.19
2000
0.00
0.00
0.02
0.27
0.74
1.82 3.86
7.34 12.60
19.03
28.50
38.36
112.53
2101
0.00
0.00
0.07
0.41
1.04
2.50 5.04
9.25 15.42
22.78
34.61
45.27
136.40
-------
TABLE 5-13: POPULATION EXPOSED ABOVE Ldn = 55 dB - OPTION 4
dB
RANGE
91.
88T
88.
85T
85.
82T
82.
79.
79.
76T
76. 73.
73T 70.
70. 67._
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
%
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
-
-
-
—
-
-
- -
-
1990
0.00
0.00
0.01
0.20
0.59
1.49
3.34
6.56 11.39
17.75
27.13
36.69
105.15
2000
0.00
0.00
0.03
0.30
0.80
1.98
4.16
7.95 13.63
21.23
33.11
43.22
126.40
2010
0.00
0.00
0.09
0.44
1.11
2.68
5.42
9.92 16.53
25.58
39.91
49.56
151.24
7%
1981
-
-
-
-
-
—
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.57
1.43
3.21
6.31 10.97
16.76
24.81
33.61
97.87
2000
0.00
0.00
0.03
0.28
0.77
1.89
3.99
7.61 13.03
19.76
29.98
40.01
117.34
2010
0.00
0.00
0.08
0.43
1.07
2.58
5.21
9.55 15.85
23.63
36.20
46.59
141.19
3%
1981
-
-
-
-
-
—
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.17
0.56
1.38
3.12
6.11 10.64
16.29
23.73
32.27
94.27
2000
0.00
0.00
0.02
0.27
0.74
1.82
3.86
7.34 12.60
19.03
28.50
38.36
112.53
2101
0.00
0.00
0.07
0.41
1.04
2.50
5.04
9.25 15.42
22.78
34.61
45.27
136.40
-------
TABLE 5-14: POPULATION EXPOSED ABOVE Ldfl = 55 dB - OPTION 5
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
%
Modified YEAR
MILLIONS
OF PEOPLE
12% 1981
—
-
-
—
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.59
1.48 3.32
6.52 11.33
17.64
26.93
36.46
104.47
2000
0.00
0.00
0.03
0.29
0.79
1.96 4.12
7.87 13.51
21.02
32.75
42.92
125.28
2010
0.00
0.00
0.08
0.44
1.10
2.65 5.37
9.84 16.41
25.35
39.52
49.31
150.07
7% 1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
2000
0.00
0.00
0.00
0.00
0.00
0.03
0.18
0.28
0.57
0.76
1.42 3.20
1.87 3.96
6.28 10.91
7.55 12.94
16.68
19.59
24.63
29.66
33.39
39.66
97.27
116.30
2010
0.00
0.00
0.08
0.42
1.06
2.56 5.17
9.49 15.76
23.45
35.86
46.31
140.15
3% 1981
-
-
-
-
-
- -
- —
-
-
-
-
1990
0.00
0.00
0.00
0.17
0.55
1.37 3.11
6.08 10.59
16.22
23.58
32.08
93.76
2000
0.00
0.00
0.02
0.26
0.74
1.80 3.83
7.29 12.52
18.90
28.23
38.04
111.64
2101
0.00
0.00
0.07
0.41
1.03
2.48 5.01
9.20 15.35
22.63
34.32
45.01
135.51
-------
TABLE 5—15: POPULATION EXPOSED ABOVE Ld = 55 dB - OPTION 6
dB
RANGE
91.
88T
88.
85T
85.
82T
82.
79T
79.
76.
76. 73.
73. 70T
70. 67.
67. 64T
64.
61T
61._
58.
58.
55T
TOTAL
%
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
—
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.01
0.20
0.59
1.49 3.33
6.54 11.37
17.71
27.06
36.61
104.91
2000
0.00
0.00
0.03
0.29
0.79
1.96 4.12
7.87 13.51
21.02
32.75
42.92
125.28
2010
0.00
0.00
0.08
0.44
1.10
2.65 5.37
9.84 16.41
25.35
39.52
49.31
150.07
7%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.18
0.57
1.43 3.21
6.30 10.95
16.73
24.75
33.53
97.65
2000
0.00
0.00
0.03
0.28
0.76
1.87 3.96
7.55 12.94
19.60
29.66
39.66
116.30
2010
0.00
0.00
0.08
0.42
1.06
2.56 5.17
9.49 15.76
23.45
35.86
46.31
140.15
3%
1981
-
—
-
-
-
- -
— -
-
—
-
-
1990
0.00
0.00
0.00
0.17
0.56
1.38 3.11
6.10 10.62
16.26
23.67
32.20
94.07
2000
0.00
0.00
0.02
0.26
0.74
1.80 3.83
7.29 12.52
18.90
28.23
38.04
111.65
2101
0.00
0.00
0.07
0.41
1.03
2.48 5.01
9.20 15.35
22.63
34.32
45.01
135.51
-------
TABLE 5-16: POPULATION EXPOSED ABOVE Ldn = 55 dB - OPTION 7
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76.
73.
73.
70.
70. 67.
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
% Modified YEAR
MILLIONS
OF PEOPLE
12% 1981
-
-
-
-
-
-
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.59
1.48
3.32
6.52 11.33
17.65
26.95
36.49
104.54
2000
0.00
0.00
0.03
0.29
0.79
1.96
4.12
7.87 13.51
21.02
32.75
42.92
125.28
2010
0.00
0.00
0.08
0.44
1.10
2.65
5.37
9.84 16.41
25.35
39.52
49.31
150.07
7% 1981
-
-
-
—
-
-
—
— —
-
—
-
-
1990
0.00
0.00
0.00
0.18
0.57
1.42
3.20
6.28 10.92
16.69
24.66
33.42
97.35
2000
0.00
0.00
0.03
0.28
0.76
1.87
3.96
7.55 12.94
19.59
29.66
39.66
116.30
2010
0.00
0.00
0.08
0.42
1.06
2.56
5.17
9.49 15.76
23.45
35.86
46.31
140.15
3% 1981
-
-
-
—
-
—
—
- —
-
—
-
—
1990
0.00
0.00
0.00
0.17
0.55
1.37
3.11
6.08 10.60
16.23
23.60
32.11
93.83
2000
0.00
0.00
0.02
0.26
0.74
1.80
3.83
7.29 12.52
18.90
28.23
38.04
111.64
2101
0.00
0.00
0.07
0.41
1.03
2.48
5.01
9.20 15.35
22.63
34.32
45.01
-------
TABLE 5-17: POPULATION EXPOSED ABOVE Ldfl = 55 dB - OPTION 8
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67. 64.
64.
61.
61._
58.
58.
55.
TOTAL
%
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
1990
2000
2010
-
0.00
0.00
0.00
-
0.00
0.00
0.00
-
0.01
0.03
0.08
-
0.20
0.29
0.44
-
0.59
0.79
1.10
- -
1.49 3.33
1.96 4.12
2.65 5.37
- -
6.55 11.38
7.87 13.51
9.84 16.41
-
17.72
21.02
25.35
-
27.08
32e75
39.52
-
36.64
42.92
49.31
-
104.98
125.28
150.07
7%
1981
1990
2000
2010
-
0.00
0.00
0.00
-
0.00
0.00
0.00
-
0.00
0.03
0.08
-
0.18
0.28
0.42
-
0.57
0.76
1.06
- -
1.43 3.21
1.87 3.96
2.56 5.17
- -
6.30 10.95
7.55 12.94
9.49 15.76
-
16.74
19.60
23.45
-
24.77
29.66
35.86
-
33.55
39.66
46.31
-
97.72
116.31
140.15
3%
1981
1990
2000
2101
-
0.00
0.00
0.00
-
0.00
0.00
0.00
-
0.00
0.02
0.07
-
0.17
0.26
0.41
-
0.56
0.74
1.03
- -
1.38 3.12
1.80 3.83
2.48 5.01
- -
6.10 10.63
7.29 12.52
9.20 15.35
-
16.27
18.90
22.63
-
27.30
28.23
34.32
-
32.23
38.04
45.01
-
94.15
111.65
135.51
-------
TABLE 5—18: POPULATION EXPOSED ABOVE Ldn = 55 dB - OPTION 9
dB
RANGE
91.
88T
88.
85T
85.
82.
82.
79.
79.
76.
76. 73.
73. 70T
70. 67.
67T 64.
64.
61.
61.
58.
58.
55.
TOTAL
—
% Modified YEAR
MILLIONS
OF PEOPLE
12% 1981
-
-
-
-
-
-
-
- -
-
-
-
1990
0.00
0.00
0.00
0.19
0.59
1.48
3.32
6.52 11.33
17.64
26.93
36.46
104.47
2000
0.00
0.00
0.03
0.29
0.78
1.94
4.08
7.80 13.39
20.79
32.33
42.58
124.01
2010
0.00
0.00
0.08
0.44
1.09
2.63
5.32
9.75 16.27
25.08
39.07
49.02
148.76
—
-
7% 1981
-
-
-
-
-
-
-
- -
-
-
-
1990
0.00
0.00
0.00
0.18
0.57
1.42
3.20
6.28 10.91
16.68
24.63
33.39
97.27
2000
0.00
0.00
0.03
0.27
0.76
1.86
3.93
7.49 12.84
19.43
29.33
39.29
115.23
2010
0.00
0.00
0.07
0.42
1.06
2.54
5.13
9.42 15.66
23.25
35.50
46.01
139.06
Th
-
3% 1981
-
-
-
-
-
-
-
- -
-
-
-
1990
0.00
0.00
0.00
0.17
0.55
1.37
3.11
6.08 10.59
16.22
23.58
32.08
93.76
2000
0.00
0.00
0.02
0.26
0.73
1.79
3.81
7.24 12.45
18.78
27.98
37.75
110.82
2101
0.00
0.00
0.07
0.41
1.03
2.47
4.98
9.15 15.27
22.49
34.06
44.75
134.67
-------
TABLE 5-19: POPULATION EXPOSED ABOVE Ldn = 55 dB - OPTION 10
dB
RANGE
91.
88.
88.
85T
85.
82T
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67T 64T
64._
61.
61.
58.
58.
55.
TOTAL
%
Modified
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
-
-
-
-
-
-
- -
1990
0.00
0.00
0.01
0.20
0.59
1.49
3.33
6.55 11.38
17.72
27.08
36.46
104.47
2000
0.00
0.00
0.03
0.29
0.79
1.94
4.09
7.81 13.41
20.85
32.43
42.66
124.30
2010
0.00
0.00
0.08
0.44
1.09
2.63
5.32
9.75 16.27
25.08
39.07
49.02
148.76
7%
1981
-
-
-
-
-
-
-
- -
-
-
-
-
.
1990
0.00
0.00
0.00
0.18
0.57
1.43
3.21
6.30 10.95
16.74
24.77
33.55
97.72
2000
0.00
0.00
0.03
0.28
0.76
1.86
3.94
7.51 12.86
19.47
29.41
39.37
115.47
2010
0.00
0.00
0.07
0.42
1.06
2.54
5.13
9.42 15.66
23.25
35.50
46.01
139.06
3%
1981
—
-
-
-
-
-
-
- -
-
-
-
-
1990
0.00
0.00
0.00
0.17
0.55
1.38
3.12
6.10 10.63
16.27
23.70
32.23
94.15
2000
0.00
0.00
0.02
0.26
0.73
1.80
3.81
7.25 12.47
18.81
28.04
37.82
111.01
2101
0.00
0.00
0.07
0.41
1.03
2.47
4.98
9.15 15.27
22.49
34.06
44.75
134.67
-------
TABLE 5—20: POPULATION EXPOSED ABOVE Ld = 55 dB — OPTION Q
U,
( )
dB
RANGE
91.
88.
88.
85.
85.
82.
82.
79.
79.
76.
76. 73.
73. 70.
70. 67.
67. 64.
64.
61.
61.
58.
58.
55.
TOTAL
% MODIFIED
YEAR
MILLIONS
OF PEOPLE
12%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.19
0.58
1.46 3.27
6.42 11.17
17.37
26.44
35.90
102.81
2000
0.00
0.00
0.03
0.29
0.78
1.93 4.07
7.77 13.35
20.72
32.20
42.47
123.62
2010
0.00
0.00
0.08
0.43
1.09
2.62 5.31
9.73 16.23
25.00
38.94
48.93
148.36
7%
1981
—
—
-
—
—
- —
- -
-
—
-
-
1990
0.00
0.00
0.00
0.18
0.56
1.40 3.16
6.20 10.78
16.49
24.02
32.85
95.82
2000
0.00
0.00
0.02
0.27
0.75
1.85 3.92
7.46 12.80
19.36
29.19
39.13
114.77
2010
0.00
0.00
0.07
0.42
1.05
2.53 5.12
9.39 15.62
23.17
35.35
45.89
138.62
3%
1981
-
-
-
-
-
- -
- -
-
-
-
-
1990
0.00
0.00
0.00
0.17
0.55
1.36 3.07
6.01 10.48
16.05
23.21
31.61
92.51
2000
0.00
0.00
0.02
0.26
0.73
‘1.79 3.79
7.22 12.41
18.71
27.84
37.58
110.34
2101
0.00
0.00
0.07
0.41
1.02
2.46 4.96
9.12 15.23
22.42
33.91
44.59
134.19
-------
for sleep disruption due to the regulation of motorcycle noise. These bene-
fits represent reductions in that proportion of impact that is attributable to
motorcycles alone.
The values of LWP contained in Tables 5—21 thru 5-23 are composite
numbers representing the total number of people exposed to motorcycle pass—
bys, multiplied by the number of motorcycle passby events to which they are
exposed, weighted by the degree of anticipated interference. For example, if
32 million people are exposed nightly to motorcycle passby noise, and each is
exposed to two separate passbys, and each passby has an independent proba-
bility of disrupting sleep of 40 percent, the total LWP displayed for that
situation would be 25.6 million (32,000,000 X 2 X 0.40). Each cell in these
tables represents such a composite number.
Again, the LWP values are indicators which are used to compare across
regulatory options, and are not absolute measures of benefits. To better
quantify the benefits of different regulatory options, the RCI and RCI* values
are used.
From Tables 5—21 through 5-23, the results of the analysis for sleep
disruption is summarized as follows:
0 Assuming no reductions in the number of modified motorcycles (propor-
tion of modified vehicles remains at the 12 percent level), the RCI
becomes increasingly negative due primarily to increases in motorcycle
operations and U.S. population growth. This trend is offset somewhat as
increasingly stringent source emission regulations are imposed.
With no motorcycle regulation (Option 1), the RCI becomes increasingly
negative even with a concurrent reduction in the number of modified
vehicles.
0 The RCI values become increasingly positive as both the proportion of
modified motorcycles is reduced and as increasingly more stringent
source emission regulations are imposed.
° Options 9 and 10 demonstrate the greatest benefits in terms of RCI*.
These benefits reach almost 50 percent in the year 2010 with no reduc-
tion in modified vehicles, and over 85 percent with an assumed three
percent modified motorcycles. The idealized Option Q adds little
additional benefit. Options 1 and 2 show the least benefit.
In 1990, RCI* benefits range from zero to 50 percent with 12 percent
modifications, and 40 to 85 percent with an assumed 3 percent modifi-
cations. The differences between options show the effects of regulatory
lead time (effective dates) on near—term benefits.
Benefits in terms of RCI* would reach in the year 2010 approximately 22
and 40 percent from reducing the proportion of modified vehicles to 7
and 3 percent, respectively, without a concurrent regulation on source
emissions.
° In terms of RCI*, benefits would reach in the year 2010 between 40 and
50 percent for the most stringent regulatory alternatives even if the
proportion of modified motorcycles were not at all reduced and remained
at the 12 percent level
5-64
-------
TABLE 5-21
Sleep Disruption 1rr acts with 12 percent
Modified Motorcycles
1980 1990 2000 2010
Regulatory
Option LWP 1 Rd 2 RCI* 2 LWP 1 RCI 2 RCI* 2 LWP 1 R d 2 RCI* 2 LWP’ R d 2 RCI* 2
Option 1
220.9
0.00
0.00
428.6
-94.02
0.00
599.0
0.00 681.
211.18
0.00
Option 2
-
-
—
388.9
-76.05
9.26
542.7
-145.68
-
9.40 622.8
-181.94
9.40
Option 3
-
-
—
296.4
-34.18
30.84
402.9
—82.39
32.74 462.4
-109.33
32.73
Option 4
-
—
—
301.6
-36.53
29.63
402.9
—82.39
3 14__ 462.4
109.33
32.73
Option 5
—
—
—
272.2
-23.22
36.68
351.9
—
—59.30
41.25 404.0
—82.89
41.23
Option 6
—
—
—
289.8
-31.19
32.38
352.1
—59.39
41.22 404.0
—82.89
41.23
Option 7
—
—
—
277.4
-25.58
35.28
351.9
—59.30
41.25 404.cL
—82.89
41.23
Option 8
—
—
—
295.1
33.59
31.15
352.1
59.39
41.22 404.0
—82.89
41.23
Option 9
-
-
—
272.2
-23.22
36.49
316.3
—43.19
47.20 362.6
—64.15
47.25
Option 10
—
—
—
295.1
-33.59
31.15
324.5
—46.90
45.83 362.6
—64.15
47.25
Option Q
-
-
-
230.0
—4.12
46.34
315.5
—42.82
47.33 362.0
-63.88
47.34
NOTES:
1 = Level Weighted Population (millions)
relative changes in in mct (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of motorcycle population modified since this represents the current estimate of
modifiec motorcycles.
-------
TABLE 5-22
Sleep Disruption Impacts with 7 percent
Modified Motorcycles
1980
1990
2000
2010
Requlatory
Option LWP’ RCI 2 RCI* 2
LWP 1 Rd 2 RCI* 2
LWP 1 RCI 2 RCI* 2 LWP 1 RCI 2 RCI* 2
Option 1
172.3
22.0
22.0
334.2
-51.29
22.03
467.O
-111.41
22.04
53593_
142.60
22.04
Option 2
—
-
-
292.6
-32.46
31.73
352.2
-59.44
41.20
468.1
—111.91
31.90
Option 3
—
-
-
196.3
11.14
54.20
262.7
-18.92
56.14
301.5
-36.49
56.14
Option 4
-
—
-
201.8
8.65
52.92
262.7
-18.92
56.14
301.5
-36.49
56.14
Option 5
-
-
-
174.2
21.14
59.36
215.8
2.31
63.97
247.7
-12.13
63.97
Option 6
-
-
-
190.3
13.85
55.60
216.0
2.22
63.94
247.7
-12.13
63.97
Option 7
-
—
-
179.5
18.74
58.12
215.8
2.31
63.97
247.7
-12.13
63.97
Option 8
-
-
-
195.8
11.36
54.32
216.0
2.22
63.94
247.7
-12.13
63.97
Option 9
-
-
-
174.2
21.14
59.36
188.3
14.76
68.56
215.7
2.35
68.62
option 10
-
-
-
195.8
11.36
54.32
194.7
11.86
67.50
215.7
2.35
68.62
Option Q
—
-
-
138.1
37.48
67.78
187.5
15.12
68.70
215.1
2.63
68.71
NOTES:
LWP = Level Weighted Population (millions)
2 The relative changes in impact (RCI and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
3
These ntinbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5—23
Sleep Disruption Impacts with 3 percent
Modified Motorcycles
1980
1990 2000 2010
Regulatory
Option LWP 1 RCJ 2
RCI* 2
LWP 1 Rd 2 RCI* 2 LW!’ 1
RCI 2 RCI* 2 LWP 1 Rd 2 RCI* 2
Option 1
132.1
40.20
40.20
256.5
—16.12
40.15
358.4
—62.25
40.17
411.1
—86.10
40.19
p ion 2
—
-
-
213.2
3.49
50.26
297.2
—34.54
50.38
340.8
-54.28
50.42
Option 3
—
—
—
114.5
48.17
73.29
147.6
33.18
75.36
169.3
23.36
75.37
Option 4
120e0
45.68
72.00
147.6
33.18
75.36
169.3
23.36
75.37
Option 5
—
—
—
93.7
57.57
78.13
104.2
52.83
82.60
119.5
45.90
82.62
Option 6
-
-—
108.9
50.70
74.59
104,3
52.78
82.59
119.5
45.90
82.62
Option 7
—
—
—
99.4
55.02
76.82
104.2
52.83
82.60
119.5
45.90
82.62
Option 8
—
—
—
114.5
48.17
73.29
104.3
52.83
82.59
119.5
45.90
82.62
Option 9
—
—
-
93.7
57.57
78.13
83.3
62.30
86.10
95.0
56.98
86.18
Option 10
—
-
-
114.5
48.17
73.29
88.1
60.12
85.29
95.0
56.98
86.3.8
Option Q
—
—
—
63.1
71.46
85.29
82.5
62.64
89.54
94.4
57.26
86.27
NOTES:
LW!’ = Level Weighted Population (millions)
2 The relative changes in in act (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to sh v the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
The second type of activity interference examined is sleep awakening.
The probability of sleep awakening is less than that for sleep disruption,
since it takes more noise, generally of longer duration, to awaken a sleeper
than it does to change the depth of sleeP state.
For sleep awakening, the LWP and both RCI and RCI* results appear in
Tables 5-24 through 5—26. These tables are organized identically to Tables
5-21 through 5-23. Again, the LWP values represent a composite of the number
of people exposed, the number of passby events, and the probability of an
1 nterference occurri ng.
These tables show a very large reduction in potential sleep awakenings
due to the regulation of motorcycle noise. The trends in RCI and RCI* for
sleep awakening are nearly identical to the trends evidenced in Tables 5-21 to
5-23 for sleep disruption. For example, Options 9 and 10 show the most
benefits in terms of RCI*, reaching by the year 2010 almost 45 percent assum-
ing 12 percent modified motorcycles, and over an 85 benefit assuming 3 percent
modified. The idealized option Q demonstrates little additional benefit.
Another type of activity interference examined is speech interference.
Discussed separately is speech interference indoors at home, outdoors at home,
and for pedestrians along streets.
For speech interference indoors, LWP, RCI and RCI* appear in Tables
5—27 through 5-29. Again, these tables are organized identically to the
previous tables. These tables show very large benefits in terms of reduced
speech interference due to the regulation of motorcycle noise. Some of the
more important trends are noted below:
Assuming no reductions in the number of modified motorcycles (12 percent
o level), the RCI becomes increasingly negative due to increases in motor-
cycle operations and U.S. population growth. This trend is offset some-
what with increasingly stringent source emission regulations.
With no motorcycle regulation (Option 1), the RCI becomes increasingly
o negative even with a concurrent reduction in the number of modified
motorcycles.
The RCI values become increasingly positive as both the proportion of
o modified motorcycles is reduced and as increasingly more stringent
source regulations are imposed.
Options 9 and 10 demonstrate the greatest benefits in terms of RCI*.
o These benefits reach almost 30 percent in the year 2010 with no reduc-
tion in the proportion of modified motorcycles, and over 80 percent with
an assumed three percent modified. The idealized Option Q shows little
additional benefit. Options 1 and 2 show the least benefits to be
gained.
Benefits in terms of RCI* would reach, in the year 2010, approximately 32
o and 58 percent by reducing the proportion of modified motorcycles to i
and 3 percent, respectively, without concurrent source regulation 5
In terms of RCI*, benefits would reach in the year 2010 between 20 and
° 30 percent for the most stringent regulatory options even if the 12
percent proportion of modified motorcycles were not reduced.
5-68
-------
TABLE 5-24
Sleep Awakening Impacts with 12 percent
Modified Motorcycles
1980 1990 2000 2010
Regu 1 atory
Option LWP’ RCI 2 RCI* 2 LWP 1 RCI 2 RCI* 2 LWP 1 Rd 2 RCI* 2 LWP’ R d 2 RCI* 2
Option 1
119.0
0.00
0.00
230.4
-93.61
0.00
321.9
-170.50
0.00
369.4
-210.42
0.00
Option 2
-
—
-
210.1
-76.55
8.81
293.0
-146.22
8.98
336.3
-182.61
8.96
Option 3
-
-
-
163.4
-37.31
29.08
222.4
-86.89
30.91
255.2
-114.45
30.91
Option 4
-
—
—
166.1
-39.58
27.91
222.4
-86.89
30.91
255.2
-114.45
30.91
Option 5
-
-
-
151.0
-26.89
34.46
196.5
-65.13
38.96
225.5
-89.50
38.96
Option 6
-
-
-
160.1
-34.54
30.51
196.6
-65.21
38.93
225.5
-89.50
38.96
Option 7
-
-
-
153.7
-29.16
33.29
196.5
-65.13
38.96
225.5
-89.50
38.96
Option 8
-
-
-
162.8
-36.81
29.34
196.6
-65.21
38.93
225.5
-89.50
38.96
Option 9
-
-
-
151.0
-26.89
34.46
177.6
-49.24
44.83
203.5
-71.01
44.91
Option 10
-
-
-
162.8
-36.81
29.34
181.9
-52.86
43.49
203.5
-71.01
44.91
Option Q
-
-
-
128.9
-8.32
44.05
171.1
-48.82
44.98
203.2
-70.76
44.99
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
-------
TABLE 5-25
Sleep Awakening Impacts with 7 percent
Modified Motorcycles
1980
1990
2000
2010
Regulatory
Option
1
LWP
2
RU
2
RCI*
LWP 1
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
RCI* 2
Option 1
23.13
23.13
176.9
—48.66
23.22
247.3
—107.82
23.17
283.6
—138.32
23.23
Option 2
-
—
-
155.6
—30.76
32.47
216.9
—82.27
32.62
249.0
—109.24
32.59
Option 3
-
—
-
107.2
9.92
53.47
143.6
—20.67
55.39
164.8
—38.49
55.39
Option 4
—
—
—
110.0
7.56
52.26
143.6
—20.67
55.39
164.8
—38.49
55.39
Option 5
—
—
—
96.0
19.31
58.32
119.9
—0.76
62.75
137.7
—15.71
62.72
Option 6
—
—
—
104.2
12.44
54.77
120.0
—0.84
62.72
137.7
—15.71
62.72
Option 7
—
—
—
98.8
17.01
57.14
119.9
—0.76
62.75
137.7
—15.71
62.72
Option 8
—
—
—
107.0
10.08
53.56
120.0
—0.84
62.72
137.7
-15.71
62.72
Option 9
—
—
—
96.0
19.31
58.32
105.6
11.26
67.19
121.0
—1.68
67.24
Option ‘10
—
-
—
107.0
10.08
53.56
108.9
8.49
66.17
121.0
—1.68
67.24
Option Q
—
—
—
77.7
34.69
66.27
105.2
11.60
67.32
120.7
—1.43
67.33
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5-26
Sleep Awakening Impacts with 3 percent
Modi fled Motorcycles
LWP’
1980
1990
LWP 1
2000
2010
RCI* 2
Regulatory
Option
Rd 2
RCI* 2 LWP 1
Rd 2
RCI* 2
R d 2
RCI* 2
LWP’
R d 2
Option 1
68.7
42.30
42.30 132.8
-11.60
42.36
185.6
-55.97
42.34
213.1
—79.08
42.31
Option 2
—
-
- 110.8
—6.89
51.91
154.2
-29.58
52.10
177.0
—48.7
52.08
Option 3
-
—
— 60.9
48.82
73.56
78.9
33.67
75.48
90.7
23.82
75.46
Option 4
-
—
— 63.7
46.47
78.9
33.67
75.48
90.7
23.82
75.46
Option 5
—
—
— 50.8
57.34
77.96
57.4
51.75
82.16
65.9
44.63
82.16
-
Option 6
-
—
— 58.2
51.13
74.76
57.5
51.68
82.14
65.9
44.63
82.16
Option 7
—
—
— 53.5
55.03
76.78
57.4
51.75
82.16
65.9
82.16
Op tion 8
—
—
— 61.0
73.54
57.5
51.68
82.14
65.9
44.63
82.16
Option 9
—
—
— 50.8
57.34
77.96
46.7
60.75
85.49
53.5
85.53
Option 10
—
—
— 61.0
48.76
49.2
-
58.66
84.72
53.5
55.08
85.53
Option Q
—
—
— 35.3
70.48
84.75
46.3
61.07
85.61
53.2
85.61
NOTES:
LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
BLE 5—27
Indoor Sp rence Impacts with 12 percent
Modified Motorcycles
-
1980
1990
2000
2010
Regulatory
Option
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
Option 1
22.5
0.00
0.00
43•93
-95.15
0.00
61.6
-174.08
0.00
71.O
-215.70
0.00
Option 2
—
-
—
42.3
—87.95
3.69
59.4
—163.98
3.68
68.4
—204.09
3.68
Option 3
—
—
—
37.6
—67.27
14.29
52.3
—132.55
15.15
60.2
—167.85
15.15
Option 4
—
—
—
37.9
—68.43
13.69
52.3
—132.55
15.15
60.2
—167.85
15.15
Option 5
—
—
—
35.7
—58.87
18.59
48.3
—114.72
21.66
55.6
—147.40
21.63
Option 6
—
—
-
37.1
—65.01
15.45
48.3
—114.76
21.64
55.6
—147.40
21.63
Option 7
—
—
—
36.0
—60.07
17.98
48.3
—114.72
21.66
55.6
—147.40
21.63
Option 8
—
—
—
37.4
-66.21
14.83
48.3
—114.76
21.64
55.6
—147.40
21.63
Option 9
—
—
—
35.7
—58.87
18.59
44.3
-96.89
28.16
51.0
—126.68
28.20
Option 10
—
—
—
37.4
—66.21
14.83
45.2
—100.93
26.69
51.0
—126.68
28.20
Option Q
—
—
—
31.6
—40.42
28.05
44.0
-95.69
28.60
50.7
—125.48
28.58
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5-28
Indoor Speech Interference Impacts with 7 percent
Modified Motorcycles
1980
1990
2000
2010
Regulatory
Option
LWP 1
RCI 2
RCI* 2
LWP 1
Rd 2
RCI* 2
LWP 1
Rd 2
RCI* 2
LWP 1
Rd 2
RCI* 2
Option 1
15.3
32.01
32.01
29.9
-32.77
31.97
42.O
-86.53
31.94
48.3
—114.94
31.92
Option 2
-
-
-
28.2
-25.34
35.77
39.6
-76.03
35.77
45.6
-102.93
35.72
Option 3
-
-
-
23.5
-4.49
46.46
32.5
-44.38
47.32
37.4
-66.43
47.28
Option 4
-
-
-
23.8
-5.69
45.84
32.5
—44.38
47.32
37.4
—66.43
47.28
Option 5
-
-
-
22.0
2.36
49.97
29.2
-29.79
52.64
33.7
—49.62
52.61
Option 6
-
-
-
23.1
-2.67
47.39
29.2
-29.84
52.63
33.7
-49.62
52.61
Option 7
-
-
-
22.2
1.16
49.39
29.2
-29.79
52.64
33.7
-49.62
52.61
Option 8
-
-
-
23.4
-3.82
46.80
29.2
-29.84
52.63
33.7
-49.62
52.61
Option 9
-
—
-
220
2.36
49.97
26.4
-17.16
57.25
30.3
-34.90
57.27
Option 10
-
-
-
23.4
-3.82
46.80
27.0
-20.05
56.20
30.3
-34.90
57.27
Option Q
-
-
-
18.8
16.45
57.19
26.1
-16.01
57.67
30.1
-33.66
57.66
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
3
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5-29
jriuuui peech Interference Impacts with 3 percent
Modified Motorcycles
1980
1990
2000
2010
Regu1atory
Option
LWP 1
Rd 2 RcI* 2
LwP 1
RCI
RCI* 2 LWI”
R d 2
2
RCI*
1
LWP
2
RCI
RCI* 2
Option I
9•43
58.15 58.15
18.4
18.41
58.19 25.8
-14.67
58.16
29.71
—32.10
58.15
Option 2
—
— —
16.7
26.19
62.18 23.4
— 3.96
62.07
26.95
—19.61
62.04
Option 3
—
- -
11.9
46.91
72.80 16.2
27.88
73.69
18.70
16.85
73.66
0_ption 4
—
— —
12.2
45.71
72.18 16.2
27.88
73.69
18.70
16.85
73.66
Option 5
—
— —
10.7
52.47
75.64 13.6
39.75
78.02
15.63
30.50
77.99
Option 6
—
- -
11.6
48.42
73.57 13.6
39.71
78.00
15.63
30.50
77.99
Option 7
—
—
11.0
51.31
75.05 13.6
39.75
78.02
15.63
30.50
77.99
0_ption 8
—
— —
11.9
47.22
72.96 13.6
39.71
78.00
15.63
30.50
77.99
Option 9
-
- -
10.7
52.47
75.64 11.7
48.02
81.04
13.44
40.24
81.07
Option 10
—
— —
11.9
47.22
72.96 12.1
46.11
80.34
13.44
40.24
81.07
Option Q
—
— -
8.3
62.92
81.00 11.4
49.27
81.49
13.15
41.53
81.48
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative. changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These nwrthers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
The results of the analysis for speech interference outdoors and for
pedestrian speech interference are displayed in Tables 5-30 through 5-32 and
Tables 5-33 through 5-35, respectively. The trends in these tables are
nearly identical to the trends for indoor speech interference. For example:
o For outdoor speech interference, Options 9 and 10 demonstrate the
largest benefits, and Options 1 and 2 the least. By the year 2010,
Options 9 and 10 show RCI* values of over 40 and 80 percent for assump-
tions of 12 and 3 percent modified motorcycles, respectively. Option Q
shows some additional benefit.
o For pedestrian speech interference in the year 2010, benefits in terms
of RCI* for Options 9 and 10 reach over 65 and 85 percent for assumed 12
and 3 percent modifications, respectively.
o For outdoor speech interference, RCI* benefits would reach by the year
2010 over 23 and 43 percent for assumed 7 and 3 percent modifications,
respectively, even with no regulation of motorcycles. Likewise, for
pedestrian speech interference benefits of over 8 and 14 percent are
demonstrated.
o For outdoor speech interference, RCI* benefits would by the year 2010
range over 30 to 40 percent for the most stringent regulatory options
with no reduction in the proportion of modified motorcycles. Likewise,
for pedestrian speech interference, benefits would range from 55 to over
65 percent.
5.9 Analysis of Noise Impact of Motorcycles Used Off-Road
This analysis adddresses the impact of regulations to limit the noise
from motorcycles used off-road. Noise from off-road use of motorcycles is
considered to be a problem of 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-road recreational vehicles (which include other factors besides noise),
trail motorcycles were rated as the “most urgent problem for them to solve”
(Reference 39). 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 that 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 ‘ 1 quite a lot”
(Reference 40).
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 (Reference 41). 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 accelera—
5—75
-------
TABLE 5-30
Outdoor Speech Interference Impacts with 12 percent
Modified Motorcycles
1980
1990
Regulatory
Option
1
LWP
2
RCI
2 1
RCI* LWP
2
RCI
2 1
RCI* LWP
2000
2
RCI
2
RCT*
1
LWP
2010
2
RCI
RCI
2
Option 1
8.4
0.00
0.00
16.3
-95.31
0.00
23.1
-175.52
0.00
Qp ion 2
—
—
-
15.4
-84.20
-218.67
0.00
Option 3
—
—
—
12.7
-51.69
22.34
21.7
17.5
—159.62
5.77
25.1
-200.26
5.78
Qp ion 4
—
—
—
12.9
—53.60
21.36
17.5
23.90
20.3
-142.17
24.01
Qption 5
—
—
—
11.8
—40.57
28.03
23.90
20.3
-142.17
24.01
Option 6
—
—
—
12.4
—48.70
23.87
—85.99
32.49
18.0
-114.56
32.67
Qp ion 7
—
—
—
11.9
—42.80
27.05
15.6
—85.99
32.49
18.0
-114.56
32.67
—
Option 8
—
—
-
12.6
—50.49
22.95
—85.99
32.49
18.0
-114.56
32.67
Qption 9
—
—
—
11.8
—40.57
28.03
13.7
- —85.99
32.49
18.0
—114.56
32.67
Option 10
—
—
-.
12.6
—49.41
22.95
14.1
40.78
15.7
—88.14
40.96
Option Q
—
—
—
9.3
—11.51
42.91
12.9
38.87
15.7
-88.14
40.96
NOTES:
43.90
14.9
—78.46
43.99
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
wfth 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
-------
TABLE 5-31
Outdoor Speech Interference Impacts with 7 percent
Modified Motorcycles
1980
1990
2000
2010
Regulatory
Option
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
Option 1
6.4
23.83
23.83
12.4
—48.70
23.87
17.6
—109.90
23.82
2O.3
-142.77
23.82
Option 2
—
-
-
11.5
—36.98
29.87
16.2
-93.16
29.89
18.7
—123.52
29.86
Option 3
-
-
—
8.7
-3.44
47.04
11.8
-41.53
48.63
13.7
—63.52
48.69
Option 4
—
—
—
8.8
—5.36
46.06
11.8
-41.53
48.63
13.7
—63.52
48.69
Option 5
—
—
—
7.8
6.71
52.23
10.0
-20.01
56.44
11.6
—38.30
56.60
Option 6
—
—
-
8.4
-0.71
48.44
10.0
-20.01
56.44
11.6
-38.30
56.60
Option 7
—
—
—
8.0
4.81
51.26
10.0
—20.01
56.44
11.6
—38.30
56.60
Option 8
—
—
—
8.6
—2.59
47.47
10.0
—20.01
56.44
11.6
—38.30
56.60
Option 9
—
—
—
7.8
6.71
52.23
8.4
—0.73
63.44
9.7
—16.02
63.59
Option 10
—
—
—
8.6
-2.59
47.47
8.8
5.10
61.85
9.7
—16.02
63.59
Option Q
—
—
—
5.6
33.16
65.78
7.7
8.27
66.71
8.8
—5.77
66.81
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5—32
uLuuuv peeCh Interference Impacts with 3 percent
Modified Motorcycles
1980
1990
2000 2010
Regulatory
Option LWP 1 Rd 2 RCI* 2
LWP’ R d 2 RCI* 2
LWP 1 R d 2 RCI*? LWP’ RCI 2 RCI* 2
Option 1
4•73
43.50
43.50
9.2
-10.39
43.48
13.O
-55.87
43.43
15.1
-80.49
43.36
Option 2
-
-
-
8.2
1.69
49.66
11.6
—38.66
49.67
13.4
—60.53
49.62
Option 3
-
-
—
5.4
35.81
67.14
7.2
14.15
68.84
8.3
0.88
68.90
Option 4
—
-
—
5.5
33.96
66.19
7.2
14.15
68.84
8.3
0.88
68.90
Option 5
—
-
-
4.6
45.19
71.94
5.5
33.85
75.99
6.4
23.74
76.07
Option 6
—
-
-
5.2
38.21
68.37
5.5
33.79
75.97
6.4
23.74
76.07
Option 7
—
—
—
4.7
43.23
70.94
5.5
33.85
75.99
6.4
23.74
76.07
Option 8
—
—
-
5.3
36.36
67.42
5.5
33.79
75.97
6.4
23.74
76.07
Option 9
-
-
-
4.6
45.19
71.94
4.2
- 50.33
81.97
4.8
42.89
82.08
Option 10
-
-
-
5.3
36.36
67.42
4.5
46.58
80.61
4.8
42.89
82.08
Option Q
—
-
—
2.5
69.64
84.46
3.4
59.68
85.37
3.9
85.43
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5-33
Pedestrian Speech Interference Impacts with 12 percent
Modified Motorcycles
1980
1990
2000
2010
Regulatory
Option
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
Option 1
16.3
0.00
0.00
32.0
-95.84
0.00
45.1
—177.40
0.00
52.2
—219.90
0.00
Option 2
—
—
-
29.2
—78.75
8.72
41.2
—151.99
8.82
47.7
—191.79
8.79
Option 3
—
—
-
19.2
-17.51
39.99
25.9
—58.30
42.72
29.9
-83.22
42.73
Option 4
—
—
-
19.8
-21.00
38.21
25.9
—58.30
42.72
29.9
-83.22
42.73
Option 5
—
—
-
16.3
0.43
49.16
19.6
-20.15
56.53
22.7
-38.82
56.60
Option 6
—
—
-
18.4
-12.68
42.46
19.6
-20.27
56.48
22.7
-38.82
56.60
Option 7
—
—
—
16.8
—3.06
47.37
19.6
—20.15
56.53
22.7
—38.82
56.60
Option 8 -
-
—
-
19.0
—16.17
40.68
19.6
-20.27
56.48
22.7
-38.82
56.60
Option 9
-
—
-
16.3
0.43
49.16
14.9
8.57
66.92
17.2
—5.21
67.11
Option 10
-
—
-
19.0
-16.17
40.68
16.0
2.02
64.55
17.2
—5.21
67.11
Option Q
—
—
-
8.7
-46.48
72.67
11.6
28.84
74.25
13.4
17.88
74.33
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate of
modified motorcycles.
-------
TABLE 5-34
Pedestrian Speech Interference Impacts with 7 percent
Modified Motorcycles
1980
1990 2000 2010
Regulatory
Option LWP 1 Rd 2 RCI* 2 LWP 1 R d 2
RCI* 2 LWP 1 R d 2 RCI* 2 LWP 1 RCI 2 RCI* 2
Option 1
15.1
7.78
7.78
29.5
-80.77
7.69
41.7
-155.24
7.64
48.3
-195.59
7.6
2ption 2
—
-
-
26.6
—62.77
16.89
37.5
-129.52
16.95
43.4
-166.01
16.9
Option 3
—
-
-
16.1
1.71
49.81
21.4
-30.92
52.63
24.8
-51.68
52.6
Option 4
-
-
-
16.7
-1.96
47.94
21.4
-30.92
52.63
24.8
-51.68
52.6
Option 5
—
-
-
13.1
19.96
59.13
15.0
7.90
66.67
17.4
—6.49
66.7
Option 6
—
-
-
15.3
6.61
52.31
15.1
7.78
66.63
17.4
-6.49
66.7
Option 7
—
-
-
13.7
16.29
57.25
15.0
7.90
66.67
17.4
-6.49
66.7
Option 8
—
—
-
15.9
2.94
50.44
15.1
7.78
66.63
17.4
-6.49
66.7
Option 9
-
-
-
13.1
19.96
59.13
10.4
36.07
76.87
12.0
26.52
77.0
Option 10
—
-
-
15.9
2.94
50.44
11.5
29.64
74.54
12.0
26.52
77.0
Option Q
—
-
-
5.4
66.76
83.03
6.9
57.46
84.61
8.0
50.94
84.7
NOTES:
LWP = Level Weighted Population (millions)
2 The relative changes in impact (Rd and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population mcdif led since this represents the current estimate of
modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
TABLE 5-35
Pedestrian Speech Interference Impacts with 3 percent
Modified Motorcycles
1980
1990
2000
2010
Regulatory
Option
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
1
LWP
2
RCI
2
RCI*
Option 1
14.O
14.39
14.39
27.4
—67.91
14.26
38.7
—137.23
14.16
44.9
-174.89
14.07
Option 2
-
—
-
24.4
—49.17
23.83
34.4
-110.47
23.84
39.9
-144.09
23.70
Option 3
-
—
—
13.4
17.76
58.01
17.7
-8.14
60.87
20.5
—25.35
60.82
Option 4
-
—
-
14.1
13.96
56.07
17.7
-8.14
60.87
20.5
—25.35
60.82
Option 5
--
—
—
10.4
36.19
67.42
11.2
31.23
75.12
13.0
20.33
75.10
Option 6
-
—
—
12.6
22.72
60.54
11.3
31.05
75.05
13.0
20.33
75.10
Option 7
-
—
—
11.0
32.39
65.48
11.2
31.23
75.12
13.0
20.33
75.10
Option 8
-
—
—
13.2
18.92
58.60
11.3
31.05
75.05
13.0
20.33
75.10
Option 9
-
-
10.4
36.19
67.42
6.7
58.85
85.11
7.7
52.76
85.23
Option 10
—
—
-
13.2
18.92
58.60
7.8
52.50
82.81
7.7
52.76
85.23
Option Q
—
2.7
83.52
91.59
3.1
81.13
93.17
3.6
78.24
93.20
NOTES:
1 LWP = Level Weighted Population (millions)
2 The relative changes in i act (RCI and RCI*) are with respect to Option 1, no motorcycle regulation,
with 12 percent of the motorcycle population modified since this represents the current estimate
of modified motorcycles.
These numbers are given to show the effect of a reduction in the number of modified
motorcycles without concurrent reductions in the sound levels of new motorcycles.
-------
tion, perpendicular to the dune buggy path. The results of this experiment
show that A—weighted sound levels ranging from 90 to 95 dB are the threshold
of unacceptability to most users (FIgure 5-16).
It is estimated that approximately one half of all recreational off-road
vehicles (ORV) use in the United States takes place on lands administered by
the Bureau of Land Management (BLM). BLM lands comprise some 20 percent of
total U.S. land area, accounting for about 60 percent of all lands owned by
the Federal government. Over half of ORV use takes place in the following
areas: Alaska, western Arizona, southern California, southern Nevada, and
central Utah.
5.9.1 Distribution of 0ff—Road Motorcycle Sound Levels
Sound levels of new non-competition off-road motorcycles are not largely
dependent upon the size of the vehicle. Because of the limited sample size
of off—road motorcycles, the assumptions used for street motorcycles in
approximating the energy-average level from the median level is invalid.
Therefore, the energy-average level is determined directly from the measured
levels in Apppendix C. The data in Appendix C for new off—road motorcycles
manufactured in 1975 and 1976 have an energy-average acceleration A-weighted
sound level (SAE J-331a) of 92.5 dB at 50 feet. 0ff-road motorcycles with
displacement of 170 cc are slightly lower.
Exhaust-modified off-road motorcycles are assumed to have the same
SAE J—331a sound level distribution as exhaust—modified street motorcycles
(shown in Figure 5-3), with a median acceleration sound level of 94 dB. The
standard deviations for the unmodified and exhaust modified off—road motor-
cycles are assumed to be the same as those for street motorcycles (shown In
Table 5-2).
Representative acceleration sound levels are assumed to be 3 dB lower
than the SAE J-331a acceleration levels, the same assumption as was made for
street motorcycles (see Appendix S).
In 1978, off-road mileage by motorcycles was approximately 12.0 millIon
miles daily and was made up of contributions from street, dual-purpose, and
off-road vehicles (Reference 42). Table 5-36 shows the off—road motorcycle
mileage mix as estimated by the Motorcycle Industry Council (MIC). According
to MIC, 50% of all off-road mileage in that year was accumulated by street and
dual-purpose motorcycles. Thus, regulation of motorcycles designed for use on
streets will have a significant effect on reducing the impact from off—road
motorcycle usage. Representative acceleration sound levels from street and
dual—purpose motorcycles were discussed in section 5.2.1.
The use of motorcycles that are designed for competition use in off—road
areas also contributes to noise impact in such areas. A-weighted sound levels
of competition-type motorcycles generally exceed 90 dB, with many exceeding
100 dB. Such levels dramatically Increase the detectability distances of
these vehicles (discussed In Section 5.9.2), resultIng in relatively large
land areas being impacted. Although the numbers of competition motorcycles
that are used off-road are not known, most land management officials contacted
by EPA reported that such vehicles constitute a very significant part of the
5-82
-------
FIGURE 5-16W SUBJECTIVE NOISE RATING OF DUNE BUGGY NOISE LEVELS
1) Very poor, noise completely unacceptable to almost all users.
2) Poor, noise unacceptable to most users.
3) Marginal, acceptable to most users.
4) Good, noise mildily offensive to some users.
5) Excellent, noise not offensive to most users.
S
CD
I-
LU
I —
C )
LU
I - )
dB SOUND LEVEL METER, FAST RESPONSE
SOURCE: REFERENCE 21
-------
TABLE 5-36 OFF-ROAD MOTORCYCLE MILEAGE MIX - 1978
I
I
I
I
I
I
I
Mileage
Estimates
I
I
I
I
I
I
‘
I
Daily
‘
Fraction
‘
I
I
Motorcycle Type
I
,
(Millions)
‘
I
of Total
I
I
I
I
I
•
I
‘
Street- Use
‘
‘
‘
‘
I
(On-Highway)
‘
I
2.7
‘
I
22%
I
I
Dual-Purpose
I
3•3
‘
28%
‘
I
I
I
I
‘
Off-Road
‘
6.0
‘
50%
I
(Off-Highway)
I
.
,
I
I
I
t
‘
‘Total
12.0
‘
100%
‘
I
I
I
I
I
I
I
I
(Source: Reference 42)
5-84
-------
off-road vehicle noise problem. Labels and other means of distinguishing com-
petition 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.
5.9.2 Detectability Criteria
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 pursuing other activities where man—made
sounds are usually undesirable. In such situations, motorcycle noise is
perceived by the listener as being alien to the environment and therefore an
objectionable Intrusion. For these reasons, “detectability” is considered
to be the best descriptor of the impact of off-road motorcycle operations. In
these situations, the criterion level for impact is the sound level at which a
motorcycle can be discerned from the background by the listener, i.e., the
minimum level at which it is detectable.
“Detectability distances” can be calculated for various types of vehicles
in recreation areas with low ambient noise levels (References 43 and 44).
Under “typical” forest conditions where the background A-weighted sound level
is assumed to be 40 dB, detectability distances of 1400, 2600, and 3900 feet
are reported for motorcycles with acceleration sound levels at 50 feet of 74
dB, 83 dB, and 93 dB, respectively (Reference 43). 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 1 percent
false alarm rate. A “40 percent hearing efficiency” means a person not only
has good hearing but is a “good listener,” i.e., the person is listening
carefully for the sound.
Because they are not necessarily concentrating on sounds, a more typical
value of “hearing efficiency” for persons in remote or rural areas would be
20 percent. If a 20 percent efficiency is assumed, the above described
detectability distances are reduced by a factor of about two (Reference 45).
Therefore, detectability distances of 700, 1300, and 1950 feet from motor-
cycles with acceleration A-weighted sound levels of 74 dB, 83 dB, and 93 dB
at 50 feet, respectively, are assumed to apply in quiet remote areas, with
typical forest background levels of 40 dB. In other areas, such as camp-
grounds, small towns, and quiet suburban communities, the background sound
levels are assumed to be on the order of 50 dB. In these areas, the detect-
ability distances are reduced to approximately 400, 700, and 1150 feet from
motorcycles for the same acceleration sound levels.
Figure 5-17 illustrates the assumed relationship between the detecta-
bility distances and the 50-foot acceleration sound levels in a 40 dB and a 50
dB ambient noise level environment. For purposes of analysis, it is assumed
that all persons within the detectability distances will perceive the motor-
cycle noise and that none beyond the detectability distance will perceive the
noise.
5-85
-------
(0.0226 )SL
MOTORCYCLE ACCELERATION SOUND LEVELS AT 50 FEET, SL, dB
FIGURE 5-17. ASSUMED DETECTA8ILITY DISTANCE OF MOTORCYCLE SOUND IN 40 dB
AND 50 dB AMBIENT NOISE LEVEL ENVIRONMENTS.
100
40 dBA AMBIENT
5 OdBA AMBIENT
U i
c o
(0. 0233 )SL
D=13.8210
FOR 40 dB AMBIENT
3.0
2.0
1.5
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
I-
w
U-
w
C-)
cC
-J
1 . -I
cC
I —
C-)
w
UJ
D=9.22’l 0
FOR 50 dB
AMBIENT
70 75 80 85 90 95
-------
5.9.3. 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 5-18 illustrates two cases of interest: the case of a
motorcycle being used on a trail or cross-country, and the case of a motor-
cycle operating within an ORV 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 significant
fraction of the straight-line distance between accelerations, the impacted
area is approximately the sum of the straight—line distances between ac-
celerations multiplied by double the criterion distance for the low-speed,
high acceleration case. Detectability as a criterion satisfies this condi-
tion. Detectability distances for off—road motorcycle noise are on the order
of one-half mile, which 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 that
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 areas impacted above a criterion
level when a motorcycle is quieted a given amount is the same for operations
on the trail or a relatively large ORV area.
5.9.4 Estimate of Current Noise Impact
The impact of noise from off—road motorcycle operations requires a
slightly different method to quantify “people impact” of off-road motorcycles
than was used in the Street motorcycle analysis. A model to estimate the
impact was developed as described below.
For illustrative purposes, it can be assumed that, on the average, there
are three motorcyclists riding together. Accordingly, three motorcycles
operating together have the effect of reducing the total mileage by a factor
of three (i.e., the total effective daily mileage becomes 40 million miles).
Further, the combination of motorcycle types assumed to be operating together
will affect the detectability distance. Since no data are currently available
to determine the likely combination of motorcycle types, an equivalent motor-
cycle noise level is derived from available statistical data concerned with
the usage and the noise levels of motorcycles operating in off-road areas.
5-87
-------
POINT OF ACCELERATION
CRITERION
DISTANCE
TRAIL/CROSS—COUNTRY
OPERATIONS
ORV AREA OPERATIONS
BOUNDARY OF ORV AREA
FIGURE 5-18.
ILLUSTRATION OF OFF-ROAD OPERATIONS.
-------
An equivalent noise level for all off—road usage is computed by summing,
logarithmically, the weighted° individual motorcycle noise levels produced by
each of the types of motorcycles used off-road. The noise level weightings
account for the distribution of off-road usage by motorcycle type and for
the percentage of motorcycles with and without modified exhaust systems.
The individual motorcycle noise levels and weightings used to compute the
equivalent noise level are shown in Table 5—37. For example, the current
levels are generated from street and dual-purpose motorcycles, making up 50
percent of the total, and off-road motorcycles, making up the other 50 percent
Of the street and dual-purpose motorcycles, 88 percent have unmodified
exhaust systems with an energy-average sound level of 79 dB (Section 5.2.1).
The remaining 12 percent of the street and dual-purpose motorcycles have
modified exhaust systems with energy-average A-weighted sound levels of
94.2 dB (Figure 5-3). The corresponding values of off-road motorcycles are 74
percent unmodified at 89.5 dB, and 26 percent modified at 94.2 dB (Figure
5—2) The equivalent noise level for this combination of unmodified and mod-
ified vehicles is 89.4 dB.
Again, for analytical purposes, it is assumed that, on the average there
are three motorcyclists riding together. The three motorcycles operating
together act as a single louder noise source. However, the detectability
distance increases only about 30 percent when three sources with the same
noise level are combined while effective daily mileage is reduced to one-third
the total daily off-road motorcycle mileage. (The effect is a reduction in
Impact by a factor of about 23 due to the three motorcycles assumption.)
Three motorcycles operating together with individual noise levels of
89.4 dB (equivalent noise level for the combination of unmodified and modified
motorcycles) act as a single source emitting 94.2 dB (an increase of 4.8 dB).
When this eqivalent noise level is used for all off-road motorcycles, the
resulting detectability distances for the 40 dB and 50 dB ambient noise level
environments are determined to be 2157 feet and 1237 feet, respectively, from
the curves shown in Figure 5-17.
As described above, the land area that is exposed daily to noise above
the detectability levels is the product of the width of the detectability path
(i.e., twice the detectability distance) and the effective daily off—road
mileage (i.e., the total daily mileage divided by 3).
Because some of the daily off-road miles will overlap, i.e., the same
or other motorcycles will impact the same area more than once, it is assumed
that the land area exposed to motorcycle noise is reduced by a factor of
50. It Is further assumed that approximately 95 percent of the total off-road
mileage by motorcycles occurs in areas where the ambient noise level is
typically 40 dB (such as forest and other rural areas) with the remaining
5 percent occurring in 50—dB ambient noise level environments (such as camp-
grounds, small towns, and quiet suburban areas).
Additionally, the population density of the areas with 40-dB and 50-dB
ambient noise levels is assumed to be 20 and 1000 persons per square mile,
respectively. On the basis of the above assumptions, it is estimated that
approximately 64,000 square miles of land area and approximately 3.12 million
people are exposed, daily to noise above detectabi1lty levels from off-road
motorcycle operations as shown in Table 5-38.
5-89
-------
TABLE 5-37
MOTORCYCLE NOISE LEVELS AND WEIGHTINGS USED TO COMPUTE
EQUIVALENT NOISE LEVELS; CURRENT NOISE IMPACT ANALYSIS
.
•
Percent of Total
‘Motorcycle ‘ Off-Road
Type ‘ Motorcycle Usage
a
‘
•
‘
Percent With and
Without Modified
Exhaust System
‘
t
A-Weighted Acce
Levels at
le
50
ration Noise
Ft. dB
‘
‘
‘
‘
Mean
L p
‘
‘
Standard
Deviation
‘ Energy-Average
Equivalent’ Lp
‘
‘
‘
I
I
I
I
I
I
‘Street and ‘
‘Dual—Purpose ‘ 50%
• I
‘
‘
I
Unmodified
Exhaust - 88%
I
‘
a
77.4
‘
‘
I
3•7
I
I 79.0
I
‘
‘
I
• a
I
I
I
,
I
• ‘
I
I I
‘
‘
S
Modified
Exhaust - 12%
I
‘
I
91.0
I
‘
I
5.3
‘
‘ 94.2
S
‘
‘
I
a ,
,
I
I
I
I
I I
I
I
I
I
I
I I
,
I
a
I
I
I I
• I
‘Off -Road 50%
‘
I ,
I
‘
‘
‘
I
Unmodified
Exhaust — 74%
Modified
Exhaust — 26%
‘
I
i
‘
,
91.0
‘
I
S
I
5.3
I
‘ 89.5
‘ 94.2
,
I
I
I
‘
,
I I
I
I
a
I
I
Total Equivalent = 89.37
-------
TABLE 5-38
ESTIMATED NOISE IPPACT IN 1978 FROM OFF-ROAD MOTORCYCLE USAGE
I
Type o
‘
f Impact
L
20
Density ‘
People/Sq. Mi :
High Density
1000 People/Sq. M i.
Total
S
I
I
I
I
I
Area
Exposed (sq. nrfles)’
62,100
1,900
64,000
I
I
S
I
I
I
I
I
I
Peopl
Detec
(m
I
e Exposed Above
tability Level
llhions)
I
1.24
I
I
‘
I
1.88
‘
S
‘
I
3.12
•
I
I
I
S
I
I
I
I
-------
5.10 Regulatory Schedules
Table 5-39 presents the regulatory options and parameters considered
in this noise impact reduction analysis. For each regulatory year considered,
two sets of data representing the percentage of off-road motorcycles with
modified and unmodified exhaust systems are assumed in the anaylses, reflec-
ting the effects of state and local enforcement programs on the percentage of
motorcycles used off-road with modified exhausts.
Five basic regulatory options are presented in Table 5—39. Option 1 is
the baseline, no regulatory condition. Option 2 represents a regulation
effective in 1982 with a not-to-exceed A-weighted level of 83 dB for street
and dual purpose motorcycles and 86 dB for off-road bikes. Similarly, Options
3 and 4, both effective in 1985, impose 80 dB limits on street and dual
purpose motorcycles, with Option 3 specifying an 86 dB not-to-exceed level for
off-road motorcycles, and Option 4 an 82 dB level. Option 5 is effective in
1990 and shows a 78 dB limit for street and dual purpose and 82 dB for off—
road motorcycles. Not shown on Table 5-39, but included in the analysis, is
Option Q (an idealized case) which represents the quieting of motorcycles to a
level of 10 dB below the most stringent regulatory option. Option Q is
included for comparison purposes to indicate an upper limit of benefits.
Each primary regulatory option is also broken into four subcategories
labeled A, B, C and U in Table 5-39. Options A and B differ from C and D in
that the latter options assume regulatory limits for off—road motorcycles less
than 170 cc at the same production level as for street and dual purpose
machines. In all cases, street and dual purpose motorcycles are assumed to
constitute 50 percent of the total off-road motorcycles usage with the other
50 percent attributable to off-road motorcycles. In the cases of Options C
and D, 37 percent of the usage is assumed to be from off—road motorcycles less
than 170 cc, and 13 percent from bikes greater than 170 cc. Note also in
Table 5-39 that Options A and C assume no enforcement at the state and local
level (7 percent and 16 percent modified for street and dual purpose motor-
cycles and off-road motorcycles, respectively), while Options B and 0 assume
complimentary state and local programs.
5.11 Results of Analysis - 0ff-Road Motorcycles
The section presents the results of the analysis to assess the relative
reduction in current impact to be expected from the regulation of noise levels
produced by motorcycles used off-road. When detectability distance is used as
the noise impact criterion, the relative reduction in impact (RCI) is calcu-
lated in the same manner as was done for the street motorcycle analysis (see
Equation 12).
Estimates of the impact resulting from the noise regulatory Options for
motorcycles used off—road are presented in Table 5-40. This table shows the
off-road equivalent noise level at 50 feet calculated using the procedure
outlined in Table 5-37, adjusted for the case of three motorcycles riding
together. Also shown are the detectability distances computed for the 40 and
50 dB ambient conditions (from Figure 5-17), the estimated areas impacted
(area of aural detectability of motorcycles), the number of people exposed
daily within this area (includes assumptions of 20 and 1000 people per square
mile for the 40 and 50 dB ambient conditions, respectively), and the relative
change in impact from baseline. These noise impact estimates presented in
5-92
-------
TABLE 5-39
PARAMETERS USED TO ASSESS THE NOISE IMPACT OF
FIDTORCYCLES USED OFF-ROAD
A—Wei ghted
Regulatory Regulatory Percent of Percent of
Option Enforcement Motorcycle Noise Level** Total Off-Road Motorcyde Type
Code Year Program* Type+ (dB) Motorcycle Usage With Modified Usage
1 1981 None S,SX None 50 12
X None 50 26
2A 1982 1 S,SX 83 50 7
X 86 50 16
28 1982 2 S,SX 83 50 3
X 86 50 8
2C 1982 1 S,SX 83 50 7
X< l7Occ 83 37 16
X> l7Occ 86 13 16
2D 1982 2 S,SX 83 50 3
XC l7Occ 83 37 8
X> l7Occ 86 13 8
3A 1985 1 S,SX 80 50 7
X 86 50 16
38 1985 2 S 1 SX 80 50 3
X 86 50 2
3C 1985 1 S,SX 80 50 7
XC170cc 80 37 16
X> l lOcc 86 13 16
30 1985 2 S,SX 80 50 3
X< l7Occ 80 37 8
X> l7Occ 86 13 8
4A 1985 1 S,SX 80 50 7
X 82 50 16
48 1985 2 S,SX 80 50 3
X 82 50 8
4C 1985 1 S,SX 80 50 7
XC l7Occ 80 37 16
X> l7Occ 82 13 16
40 1985 2 S,SX 80 50 3
XC l7 Occ 80 37 8
X> l7 Occ 82 13 8
5A 1990 1 S,SX 78 50 7
X 82 50 16
58 1990 2 S,SX 78 50 3
X 82 50 8
SC 1990 1 S,SX 78 50 7
X< l7Occ 78 37 16
X> l7Occ 82 13 16
SD 1990 2 S,SX 78 50 3
X< l7Occ - 78 37 8
X> l7Occ 82 13 8
* 1 = Federal regulation without state and local programs.
2 = Federal regulation with state and local programs.
+5 = street, SX = dual purpose, X = off—road.
**Not..to..exceed noise levels as measured by EPA test procedures.
5 -93
-------
TABLE 5-40
ESTIMATED IMPACT RESULTING FROM VARIOUS NOISE REGULATORY
OPTIONS FOR MOTORCYCLES USED OFF-ROAD
Detectability, Noise Impact Estimates
Off-Road Distance, Ft
Regulatory Equivalent
Option Code Noise Level 40 dB 50 dB Area People Exposed Daily Percent
From Table 5-39 at 50 ft (dB) Ambient Ambient Impacted Above Detectability Reduction
(From Figure 5—17) (Sq. Miles) Level (Thousands)_’ (RCI)
1 94.14 2,157 1,237 63,969 3,116 -
2A 90.67 1,790 1,032 53,094 2,595 16.73
2B 88.53 1,596 923 47,343 2,317 25.64
2C 90.43 1,768 1,020 52,442 2,563 17.75
2D 88.09 1,560 903 46,277 2,266 27.27
3A 90.49 1,774 1,023 52,620 2,571 17.47
3B 88.22 1,571 909 46,603 2,282 26.78
3C 90.12 1,739 1,003 51,582 2,521 19.08
3D 87.51 1,512 876 44,854 2,198 29.47
4A 90.08 1,736 1,002 51,494 2,518 19.20
4B 87.44 1,506 872 44,676 2,188 29.78
4C 90.01 1,728 998 51,257 2,507 19.54
4D 87.28 1,493 865 44,291 2,171 30.34
5A 90.01 1,728 998 51,257 2,507 19.54
5B 87.30 1,495 866 44,350 2,173 30.27
5C 89.88 1,717 991 50,931 2,491 20.07
5D 87.03 1,473 854 43,699 2,142 31.25
Q ./ 86.43 1,427 828 42,335 2,077 33.35
/ Calculated using procedure outlined in Table 5-37, adjusted by 4.77 dB for three motorcycles
riding together (see Section 5.9.4).
.?./ Assumes 20 people per square mile in the 40 dB ambient condition, and 1000 people per square
mile in the 50 dB ambient (see Section 5.9.4).
/ Option Q represents a level 10 dB below the most stringent regulatory level.
-------
Table 5-40 are made for conditions assuming that the entire fleet consists of
regulated vehicles. This is different from the methods used to estimate the
impact of street motorcycle noise (Section 5.8) where specified sales growth
and depletion rates were used on a year-by-year basis. Note also that this
analysis predicts the extent of Impact only. No allowance has been made for
the varying degrees of severity of exposure within the computed detectability
areas. An artifact of this is that the RCI values presented in Table 5-40 may
seem to be comparatively lower than those values computed (Section 5.8.2)
using the single-event activity interference model which duly considers both
the extent and severity of the impact. Nevertheless, relative comparisons
between regulatory options for the analysis of motorcycles used off-road
remain valid.
From Table 5—40, the results of the analysis show estimates of the area
impact off-road ranging from over 42,000 square miles to about 64,000 square
miles depending upon the regulatory option. Likewise, the number of people
estimated to be exposed above the criterion level range from over 2,000,000 to
over 3,000,000 people. All regulatory options provide significant lessening
of impact relative to the base (no regulation) condition. Option 5 is typi-
cally the most effective in reducing impact, while Option 2 is the least
effective. For example, Option 5A shows a 20 percent reduction in impact
compared to a 17 percent reduction for Option 2A. Option Q shows only a
slight additional benefit from that of the most stringent regulatory option
examined (Option 50).
The results in Table 5-40 also show that regulating off-road motorcycles
under 170 cc to a less stringent level yields less benefit. For example,
Option 4C show a 20 percent reduction in impact compared to the 19 percent
benefit of Option 4A. On the other hand, the level of enforcement assumed has
a very significant effect of benefits to be expected. For example, Option 4A
with no complimentary state and local program would result in a 19 percent
reduction in impact, while Option 4B with a concurrent program is anticipated
to yield an almost 30 percent benefit. As was shown in the analysis of
benefits of reducing noise from street motorcycles (Section 5.8), substantial
benefits are shown as the number of modified motorcycles is decreased concur-
rent with source emission regulation.
5-95
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REFERENCES
SECTION 5
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Information, Geneva, Switzerland, 1948.
2. U.S. Environmental Protection Agency, “Public Health and Welfare Criteria
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3. u.s. Environmental Protection Agency, Notice of Rulemaking for Medium
and Heavy Truck Noise Emission Standards, Federal Register (41 FR 15538),
April 13, 1976.
4. U.S. Environmental Protection Agency, Notice of Proposed Rulemaking
for Bus Noise Emission Standards, Federal Register (42 FR 45776),
September 12, 1977.
5. Survey of Motorcycle Ownership, Usage and Maintenance, A Gallup Organi-
zation, Inc. survey conducted for the Motorcycle Industry Council,
Inc., Report GO 7458, January 1975.
6. Johnson, D.R., “A Note on the Relationship Between Noise Exposure and
Noise Probability Distribution,” National Physical Laboratory, NPL Aero
Report Ac 40, May 1969.
7. Plotkin, Kenneth J., “Average Noise Levels for Highway Vehicles,” Wyle
Research Technical Note 79-2, September 1979.
8. US. Environmental Protection Agency, “Information on Levels of Environ-
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Adequate Margin of Safety,” EPA Report 550/9—74-004, March, 1974.
9. “GuIdelines for Preparing Environmental Impact Statements on Noise,”
Report of Working Group 69, Committee on Hearing, Bloacoustics and
Biomechanics, the National Research Council, Washington, D.C., 1977.
10. Schultz, Theodore J., “Synthesis of Social Surveys on Noise Annoyance,”
The Journal of the Acoustical Society of America , 64(2), 377-405,
1978.
11. Goldstein, Jeffrey, “Assessing the Impact of Transportation Noise:
Human Response Measures”, In Proceedings of the 1977 National Conference
on Noise Control Engineering, G.C. MaTing [ Ed.T, Noise Control Foundatjojj
Poughkeepsie, N.Y., pp. T9—98, 1977.
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Noise Section, Department of Ecology, State of Washington, Olympia, WA
98504, 16 April 1975.
13. “Motor Vehicle Noise Identification and Analysis of Situations Contribut-
ing to Annoyance,” Bolt Beranek and Newman Inc., Report 2082, June 197i..
5-96
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14. Mills, C.H.G. and D.W. Robinson, “Appendix IX -—- The Subjective Rating
of Motor Vehicle Noise,” Noise --- Final Report , Cmnd 2056 Her Majesty’s
Stationary Office, London, July 1963.
15. Report in preparation on community attitudes to noise In Boulder,
Colorado, EPA regional office, Denver, Colorado.
16. Gunn, W., 1. Shighehisa, and W. Shepherd, “Relative Effectiveness
of Several Simulated Jet Engine Noise Spectral Treatments in Reducing
Annoyance in a TV-Viewing Situation, NASA Langley Research Center,
Draft Report, 1976.
17. Pearsons, K.S. and R.L. Bennett, “Effects of Interior Aircraft Noise
on Speech Intelligibility and Annoyance,” National Aeronautics and
Space Administration Report, NASA CR-145203, August 1977.
18. Fidell, Sanford, “The Urban Noise Survey,” U.S. Environmental Protection
Agency Report No. 550/9-77-100, August 1977, and “Nationwide Urban Noise
Survey”, The Journal of the Acoustical Society of America , 64(17),
198-206, 1978.
19. Borsky, Paul N., “The Use of Social Surveys for Measuring Responses to
Noise Environments” In Transportation Noises: A Symposium on Accepta—
bilty Criteria , J.D. Chalupnik (Ed.), University of Washington Press,
Seaftie, pp. 219—227, 1970.
20. “Noise-Final Report,” Cmnd. 2056, Her Majesty’s Stationary Office,
London, July, 1963.
21. Grandjean, E., P. Graf, A. Lauber, H.P. Meier, and R. Muller, A Survey
of Aircraft Noise in Switzerland, In Proceedings of the International
Congress on Noise as a Public Health Pr biem , Dubrovnik, Yugoslavia,
May 13-18, pp. 645-659, 1973.
22. Sorenson, S., K. Bergiund, and R. Rylander, “Reaction Patterns in
Annoyance Response to Aircraft Noise,” In Proceedings of the Interna-
tional Congress on Noise as a Public Health Problem , Iiubrovnlk,
Yugoslavia, May 13—18, pp. 669—677,1973.
23. Gunn, Walter J., “A General Discussion of ‘Reactions to Aircraft Noises’,”
In Reaction to Aircraft Noises: A Symposium Report , E.A. Ailvis (ed.),
Journal of Auditory Research , 15, Supplement 5, pp. 214-217, 1975.
24. Hall, F.L. , SM. Taylor, and S.F. Birnie, “Coninunity Response to Road
Traffic Noise”, McMaster University, Hamilton, Ontario, Canada, December
1977.
25. McKennel, A.C., “Aircraft Noise Annoyance Around London (Heathrow)
Airport”, U.K. Government Social Survey Report SS.337, 1963.
26. Swing, John W., “A Case for Single-Event Intrusion Criteria in Achieving
Noise-Compatible Land Use,” Noise Control Engineering , 11(3), 98,
1978.
5-97
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27. Allen, J.D., L.L. Faulkner, F.G. Ren, and A.M. White, “The Automobile As
a Component of Coniiiunity Noise,” Phase 1 Final Report, Battelle Columbia
Laboratories, June 1978.
28. Lukas, J., “Measures of Noise Level: Their Relative Accuracy in Predict-
Ing Objective and Subjective Responses to Noise During Sleep,” U.S.
Environmental Protection Agency Report No. EPA-600/1-77-O10, February
1977.
29. Lukas, J., “Noise and Sleep: A Literature Review and a Proposed Criteria
for Assessing Effect,” The Journal of the Acoustical Society of America ,
Vol. 58 (6), pp. 1232—1242, 1975.
30. Plomp, R. and A. M. Mimpen, “Speech Reception Threshold for Sentences
as a Function of Age and Noise Level,” The Journal of the Acoustical
Society of America , 66(5), 1333-1342, 1979. —
31. Rudder, F.F., L. Ronk, and B.A. Hutcheson, “National Roadway Traffic
Noise Exposure Model,” Report prepared for the U.S. Environmental
Protection Agency by Science Applications, Inc., 1979.
32. Ma, Y.Y., and F.F. Rudder, “Statistical Analysis of FHWA Traffic Noise
Data”, U.S. Department of Transportation, Federal Highway Administration,
Report FHW-RD-78—64, July 1978.
33. Gray, R. F., “A Survey of Light Vehicle Operations”, Engineering
Publication 6313, General Motors Proving Ground, Milford, Michigan, July
1975.
34. Sakagami, J., “Consideration of Moise Emission of Road Vehicles on
Urban Streets in Japan,” Proceedings Inter—Noise 75, Tokyo University,
Sendai 980, Japan, pp. 21-28, 1975.
35. “National Functional System Mileage and Travel Summary”, U.S. Department
of Transportation, Federal Highway Adminstratlon, Office of Planning,
June 1977.
36. “National Highway Inventory and Performance Study Manual, 1976,” U.S.
Department of Transportation, Federal Highway AdministratIon, July
1975.
37. “The Status of the Nation’s Highways: Conditions and Performance,”
Report of the Secretary of Transportation to the United States Congress,
95th Congress, 1st Session, (45-29) U.S. Government Printing Office,
September 1977.
38. “1970 Census of Population, Number of Inhabitants, United States Summary,”
U.S Department of Conhlierce, Bureau of Census, Decen er 1971.
39. 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.
40. Shepherd, “A Preliminary Study of the Annoyance Due to Noise From
Recreational Vehicles,” Laboratory for Hearing Studies and Noise Con-
trol, University of Utah, Report T.R. 75-001,. 1975.
5-98
-------
41. 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, July 1973.
42. “1978 Motorcycle Statistical Annual,” Motorcycle Industry Council,
Inc., Research and Statistics Department, 1979.
43. HarrIson, R.T., “Off-Road Vehicle Noise-Effects on Operators and By-
standers,” U.S. Department of Agriculture, Forest Service, Report 740687,
prepared for Society of Automotive Engineers, National Combined Farm,
Construction and Industrial Machinery and Powerplant Meetings, Milwaukee,
WI, September 9-12, 1974.
44. Fidell, S., K.S. Pearsons and R.L. Bennett, “Predicting Aural Detecta-
bility of Aircraft in Noise Backgrounds,” Bolt Beranek and Newman Inc.,
Cambridge, MA, Report 220-AFFDL—TR—72—17, July 1975.
45. Harrison, R., private communication, U.S. Department of Agriculture,
Forest Service, October 1976.
46. HarrIson, R.T., “Sound Propagation and Annoyance Under Forest Condi-
tions,” U.S. Department of Agriculture, Forest Service, Equipment Devel-
opment Center, San Dimes, CA, Report 7120—6, March 1974.
47. “1975 AutomobIle Facts & Figures”, Motor Vehicle Manufacturers Associa-
tion, Detroit, Michigan 48202.
48. “American Trucking Trends 1975,” American Trucking Association, Inc.,
Washington, D.C. 20036, 1976.
49. Kent, P. and M. Branes: “1975 NatIonal Truck Characteristic Report”,
U.S. Department of Transportation, Federal Highway Administration, April
1978.
50. Galloway, W.J., K. Eldred, and M.A. Simpson, “Population Distribution
of the United States as a Function of Outdoor Noise Level,° U.S. Environ-
mental Protection Agency Report No. 550/9—74—009A, June 1974.
51. Wyvill, C. (Ed.), “Discussion of Sound Propagation,” Technical Meeting,
U.S. Environmental Protection Agency, Office of Noise Abatement and
Control, held at Crystal CIty, 14 October 1977.
52. “An Assessment of the Technology for Bus Noise Abatement,” Booz Allen
Applied Research, Draft Final Report submitted to U.S. Environmental
Protection Agency, Office of Noise Abatement and Control, EPA Contract
No. 68-01-3509, June 22, 1976.
53. Sutherland, L.C., “Indoor Noise Environments Due to Outdoor Noise
Sources,” Noise Control EngIneering, 11(3), 124-137, 1978.
5-99
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SECTION 6
NOISE REDUCTION TECHNOLOGY
-------
SECTION 6
NOISE REDUCTION TECHNOLOGY
6.1 Diagnostic Evaluation of _ N _ oi Sources
Many of the manufacturers which EPA and its motorcycle technology
contractor visited have performed and/or sponsored comprehensive diagnostic
studies on motorcycle noise source contributions, and have defined the
major noise-producing components and the levels of noise produced by these
component sources both individually and in combination. The diagnostic
techniques employed for Identification of noise source contributions, and the
specific noise control methods being employed or studied by the different
manufacturers, 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, “niechanical” encompasses
noise 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 noise levels. The vehicles
are listed in descending order of total noise 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 noise level,
use category, and engine type. There is also no relationship or trend
between engine displacement and source contribution.
The noise reduction techniques necessary to meet a particular emission
standard will vary widely from motorcycle to motorcycle, and are very diffi-
cult to place in a generally-applicable matrix of vehicle category/subcategory
vs. noise level. For example (referring to the Table), to reduce noise
emissions of vehicle “0” currently at 83 dB to 80 dB would require attention
primarily to the exhaust which is contributing 84 percent of the noise; this
might be attained relatively easily. On the other hand, for vehicle “H”,
currently at 82 dB, the attainment of an 80 dB level would require quieting
the mechanical sources, which might constitute a major engineering effort.
6.2 Noise 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 noise emissions centers around the
exhaust system, air intake system, and the mechanical/drive components.
In approaching the noise reduction problem, manufacturers generally treat
the exhaust and intake noise sources first because modification of these
sources generally impact the basic model configuration least.
* ssupp11e b3 : H id1TY ama liii i a17 iiitiI 1 WäITé3i
Davidson. Other manufacturers visited also supplied data used in this
analysis.
6-1
-------
Table 6—1
NOISE SOURCE CONTRIBUTION, 1976 IUDEL MOTORCYCLES
Total Category_* % Coritributionof Noise Source
Vehicle
Ioise Vehicle Use Engine Exhaust Intake Mechanical**
Level deference Type
dB Letter
84 S 4S 60 3 37
83 B S 4S 35 55 10
83 C S 23 24 30 46
83 0 SX 2S 84 5 11
82.5 E S 43 47 5
82 F S 4S 30 35 35
82 G S 2S 24 38 38
82 H S 2S 6 4 90
82 I S 2S 6 63 31
81 J S 2S 1 ]. 50 39
80.5 K SX 2S 28 31 41
80 L S 4S 10 64 26
80 M SX 4S 28 18 54
80 N SX 23 51 16 33
80 0 SX 2S 33 30 37
79.5 P S 4S 25 18 57
79•5 Q SX 23 1 79 20
79.5 R S 4S 32 35 33
79 S S 43 26 20 54
77.5 T S 4S 66 20 14
77 U SX 4S 42 22 36
Sde noTes — _______
SX denotes Combination Street and.Off-road 1otorcyc1e
2S denotes 2 stroke
45 denotes 4 stroke
** ‘ 1 MechanicaV’ includes engine, trans ission, chain, frame, ancillary
equipment, tires and wind noise.
6-2
-------
Exhaust noise is generally reduced by using one or more of the follow.-
ing 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; interconnecting header pipes
on tnulticylinder inotorcyles (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 noise
levels, generally at some penalty in increased backpressure. Such techniques
include adding! modifying reactive chambers, adding or sealing baffles,
modifying the core pipe, inserting noise absorption lining and 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 noise emitted from the exhaust outlet,
but reduce radiated noise from the muffler shell.
These techniques can be summarized:
o Increase muffler volume
o Interconnect exhaust pipes
o Modify interior
o Add noise absorptive lining
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. The shell dampening can be accomplished by the use of thicker
6-3
-------
or different material, reinforcement, or double wall construction. The
techniques used to control air intake systems can be surimiarized as follows:
o Increase volume
o Modify inlet
o Modify interior
o Add noise 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 noise reduction required. Various techniques
currently in use and mentioned by manufacturers as possibilities for future
models are suri uar1zed as follows; and are described in the following paragraphs:
o StIffen/dampen fins and case webs o Stiffen crankshaft
o Change fin shapes o Redesign clutch and
transmission
o Thicken/reinforce components
o Improve chain tensioner
o Improve component mounting
o Enclose drive chain
o Thicken/reinforce case covers
o Dampen/isolate chain cover
o Isolate case covers
o StIffen/frame; Isolate
o Increase lubrication engine
o Modify piston/cylinder o Lower engine speed
o Reduce tolerances/Improve finish o Reduce specific horsepower
o Modify bearings o Liquid cooling
o Modify timing/drive belts/chains o Convert 2—stroke to
4-stroke engine
6-4
-------
o Modify camshaft o Reconfigure engine to
reduce dynamic unbalance
o Reduce valve clatter forces
o Increase flywheel mass 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.
ThickenJrelnforce case covers-—Includes use of thicker material, rein-
forcement ribbings or double covers on such elements as gear covers, crankcase
covers, camshaft covers and so forth.
Isolate case covers--Use of elastoniers to reduce vibration and radiated
noise,
Increase lubrication--Providing additional pressure lubrication to
reduce mechanical 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
mechanical 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.
6—5
-------
Stiffen crankshaft-—To increase rigidity and reduce mechanical inter-
action noise.
Redesign clutch and transmission—-Use of helical gears instead of
spur gears to reduce mechanical interaction noise; use of journal type
bean ngs.
Improve chain tensioner--To reauCe chain/sprocket interaction flOise
and chain tensioner noise.
Enclose drive chai n—-To attenuate dri ye chai n noi se.
ii& ipen/isolate chain cover--To eliminate cover vibration and radiated
fbi se.
Stiffen/dampen frame; isolate engine--To prevent radiated noise due
to engine vibration transmitted to the frame and to components mounted on
the frame.
Lower engine speed -To reduce mechanical interaction noise.
Reduce speci fic horse-power--To reduce the exci tation forces Which
result in engine noise radiation.
The above noise reduction techniques range fron detail changes to
significant redesi;n. For some models reductions in i echanical/drive noise
levels to meet stringent noise standards would require techniques 1nvolvi g
complete redesign of the engine and drive train. In addition, some of the
techniques would result in reduced engine performance. As discussed I
Section 4.1, it is impossible to predict by product categories which specific
regulatory levels will require major aodel changes. The lowest levels that
any of the manufacturers have reported as being feasible for the near-term is
80 dB for street motorcycles, 84 ib for off-road motorcycles. Other nanufäc..
turers question that an 80 d 3 noise standard can be met without major redesign
on some models. ‘1ajor model configuration changes could include the use of
such techniques as conversion 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
iajor engine/ drive redesi jn not specified here. These techniques would all
require major changes in riianufacturing operations, and extensive lead time.
These techniques, not necessarily feasibl3 in all use categories, are dj
cussed in the following paragraphs.
Liquid Cooling-—Liquid cooling, because it allows reduced clearances
in engine parts, arid because it provides added shielding around the engjrie
cylinders, can materially reduce engine radiated noise. Conversion to liquid
cooling would require re—engineering and re—tooling of the engine, ddd Signif-
icant weight, and add to unit manufacturing costs. Additional hardware is
required to inplerient liquid cooling, including a pump, radiator, therrnost, t
coolant, 1umbing, instrumentation and recasting of the cylinder head and
walls. Feasibility of liquid cooling for off-road 4 iotorcycles is very ques-
tionable because of vulnerability of tne radiator to damage from rocks and
spills.
b-5
-------
4-Stroke vs. 2-Stroke Engines--Some manufacturers feel that 4
engi nes are easier to quiet than 2—stroke engi nes. Because of this Stroke
sion of engine types is a potential option. This alternative aiso’ COflver
by the fact that exhaust cheriical emissions are more difficult to co t
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 ur t
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 OppOSiflY
cylinders, counter—rotating crankshafts, or balanced VH configurdt1O s.
These methods can involve dynamic vibration absorbers or coUflt3r_r0tdthT 9
balancing elements.
Shaft Drive--Shaft drive is an option that would reduce drive train
noise on large (over 750 cc) and ?ossibly nedid [ sized (450-749 cc) on-road
motorcycles. Shaft drive on models intended some off-ruad use 15 less
attractive, because of weight constraints and flexibility requirer!iCntS in
the drive train that are required for these models. Shaft drive affects
many of the other coc.iponents on the ; iotorcycle, and is a relativelY expen-
sive option. A more cost-effective method of reducing drive noise ii I )OSt
cases would be to fully enclose the chain, which was identified previouSlY
as a noise reduction measure.
Hydraulic Torque Converter-—Another techni ue that ould involve major
i odel configuration change is converting from a stdndard transfliSSlOfl to a
hydraulic torque converter and a hydraulic gear engageient clutch, as exelilpil—
fied by the transmission on the 1onda 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 ii
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 ¶notorcycles, since styling is an i.uportant factor affecting
demand for motorcycles. Engine enclosure would entail added weight, and could
hamper access for servicing.
Although there is no generally—applicaole set of techni. ues that will
achieve specified regulatory lev2ls 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 oelow 33 dB, a schedule of techniques other than major model cnanqes are
shown for each product class. Manufacturer information enerally indicates
that all techniques discussed above would ue necessary to achieve a 75 dB
level for models above 110 cc. Fewer of these tec ini ues, or less extensive
use of these techniques, are expected to oe necessary at higher levels. For
costing purposes two estimates were made at each study level below 83 dB: On
assuming no major model change necessary, and one assuming a major niodel
6—7
-------
Table 6-2
NOISE REDUCTION TREATMENTS ASSUMED FOR EACH STUDY LEVEL
(J33 1a - NOT TO EXCEED BASIS)
x
x
xxx xxx K
xxx xxx x
xxx xxx
xxx xxx
xxx xxx
xxx
xxx
xxx
xx
xx
xx
xx
xx
x
xx
x
x
xxx
xxx
xxx
xx
xx
xx
xx
xx
K
xx
x
x
x x
xxx x
xxx
xxx x
xxx
xxx
xxx
xxx
xxx
xx
xx
xx
xx
K
xx
xxx
xxx *
xx
K
x
xx
xx
xx
K
x
xx
x
x
xxx
xxx
xx
750 + cc
83 80 78 75
xxx x
xxx x
xxx x
xxx
xxx
K
350 — 749 cc
83 80 78 75
xxx x
xxx x
xxx x
xxx
xxx
x
cc
100 — 169 cc
83 80 78 7 -
170 — 349 CC
83 80 78 75 —
xxx x
xxx x
xxx x
xxx
xx
100 cc
83 80 78 75
xxx
xxx
x
xxx
xxx x
xxx
xx
S I!ST i
IN EASE MUFFL VOU7 E
ci ss x Ec’rIc s
MCDTr! YT PTflR
NOISE ABSORPTIVE LINING
INCRFJ SE SHELL ThICKNESS
DUBLE WALLS
AIR INTAKE SYSTL14
INCREASE VOUJME
MODIFY INLET
M(W TFV J1’PTO
NOISE ABSORPTIVE LINING
INCREASE WALL ThICkNESS
MECI IAN ICAL/DRIVE SYSTE}I
STI FFEN/Dr MPD FINSA, El3S
I1IPRcWED P NE T MOUWrI
THICKEN/PEINIFORCE CASE COVE
INCREASE WDP.ICATIC J
MODIFY P1 )N/CYLINDER
R}DIXE ‘IOLERt ES/IMPROVE FINI 1
MODIFY I3EARINGS
MODIFY TIMING/DRIVE BELTS/CHAI
REDUCE W LVE CLA ER (4 ST}()KE)
INCREASE FL’ Wt1EEL MASS
MODIFY CRNKSHAT/CA SMAP1’
MODIFY CEARS/IRANSMISSICt
TIG -fl’EN Q{AIN
CLASE Q AIN
MODIFY FRAME
x
K
K
K
x x
x *
-------
change. As shown, the major model change assur’imed 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
odel changes at different regulatory levels. A few are expected to require
them at an 80 dB level, a substantial number are expected to need them at
78 dB, and virtually all are expected to need them at a 75 dB level.
6.3 Impacts of Noise Reduction Technology
6.3.1 Performance Inpacts
Each of the techniques cited above can have impacts on motorcycle perfor-
mance 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 noise 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 acnieving current
noise levels. From these data it is apparent that additional noise 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 nay cause additional weight penalties.
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 noving parts. The combination of these ir asureS
could increase engine weight by 10 to 15 percent. In addition, major engine
modifications can result in a significant vehicle weight increase. One manu-
facturer estimated an increase of 10 percent in vehicle weight for liquid
cooling (about 50 lD. for large motorcycles). Conversion of single cyclinder
2-stroke engines to sinyle—cyclinder 4—stroke engines could cause an increase
of up to 30 percent 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.
6.3.2 Operation Impacts
The only significant impact of noise 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 consumption penalty.
6-9
-------
Table 6-3
*
POWER LOSS ASSOCIATED WITH ACHIEVIr G CURRENT LEVELS
Uoise Level
4otorcycle Reduction (dB) Power Loss
a 4 12% over 6,000 RPiI
b 4 2%
c 2 30%
d 2 30%
e 0.6 3%
f 2 1”
g 2 3%
h 2.5 2R%
i 1.6 1%
j 3.5 10%
k 1 6%
1 8 up to 28%, 10% at peak
in 6 (approx) 12-1S7 (peak; very little
below 4,000 RPI1,
severe roll off
past pe. ik)
ó iTfd t I aT FéF Ifi
6-10
-------
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 170 cc 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%
100-169 cc : One-half of above figures
Less than 100 cc : 0% at all levels
Manufacturers supplied very little data on fuel econor y impacts of
achieving current or future noise levels. The little data that was furnished
indicated that the 3 to 4 dB reductions to achieve current levals resulted in
up-to—15 percent loss in fuel economy, although some models showed no change
or an improvement. Experience with trucks and automobiles indicates that a 13
percent decrease in fuel economy for a 10 percent ieight incredse 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 back—
pressure and other penalties are included.
6.3.3 Maintenance Impacts
Several of tne quieting techniques cited either require additional
maintenance or nake 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
engi nes. Complex mounting techniques, addi tional covers, reduced engine
tolerances, valve train complexities and enclosed final drive will complicate
routine maintenance, t o definitive data on the iaintenance impacts of these
techniques are available. For the purposes of analysis the following addi-
tional annual maintenance tiie (in hours) is assumed:
Regulatory_Level
Over 170_cc 85dB 83dB 80dB 78dB 75dB
Street: Straight forward change 0 1/4 3/b 1/2
Major model change 3/4 7/8 1
Off-Road: Straight forward change 0 1/4 3/8 1/2
Major :nodel change - 3/4 7/8 1
100-170 cc : One-half of above figures
Under 100 cc : Zero at all levels
6—11
-------
Noise 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 noise reduction technology
may be even more important than performance or cost impacts. 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 noise levels of all nominally identical surface transportation
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 noise 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 1/2 dB below an applicable standard
to account for production variations.
Table
6-4
PRODUCTION
VARIATION
Manufacturer Production Variation (dB )
a 2Ø= 3-4
b 1.5-2.5
c 10— 0.25 - 0.6
d 2-stroke: 1.5
4-stroke: 2.0
e 1.5
Source: Manufacturer Conffd tfal DaEi
6-12
-------
65 “ 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 motor-
cycles. Large and complex exhaust and intake systems have been demonstrated
on a wide variety of production vehicles. Weight, positioning, and perform-
ance 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
multicylinder engines. Double-wrapped mufflers have been used in several
models and prototyies, 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 program 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 manufac-
turers 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 50 cc) has been demonstrated by one European
manufacturer.
Shaft—drive has been well demonstrated on motorcycles 500 cc and above.
Based on an examination of motorcycle models incorporating the techniques
discussed above, EPA has concluded that the 78 dB regulatory level (SAE J331a),
requiring a 75 dB design level, Is the level representative of “best available
technology” for street motorcycles. 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 level on a production basis.
“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 noise levels than for street
motorcycles of comparable displacement. The inappropriateness of applying
liquid cooling to off—road motorcycles leads to different levels of “best
available technology” for large and small off-road motorcycles. Small off-road
motorcycles (under 170 cc) are expected to be able to achieve
6-13
-------
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 170 cc have multicylinder engines, whereas
off-road motorcycles must be single cylinder). Both small and large off—road
motorcycles can currently meet the 86 dB level. To meet levels at 80 dB and
lower, conversion from 2-stroke to 4-stroke engines may be necessary for large
off-road motorcycles. An 82 dB level can be met by large off-road riotorcycles
without conversion to 4—stroke engines. EPA has concluded that this 80 dB
regulatory level constitutes “best available technology” for the large
off-road motorcycles and 78 dB for small off-road motorcycles. It is under-
stood that although these levels are achievable, the perfornance of large
2—stroke off—road motorcycles will be reduced significantly in many cases.
Although all of the techniques constituting “best available technology”
exist in production or prototype motorcycles, not all manufacturers 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 impact on marketing position
(Harley—Davidson, BMW, Moto Guzzi, Ducati), manufacturers whose products have
been developed from racing motorcycles and depend on high performance
(Laverda) smaller manufacturers of high-performance off-road motorcycles
(Can—Am, Husqvarna, Bultaco, etc.) and small manufacturers without large R&D
capability (NVT Motorcycles and the very small U.S. manufacturers).
6.6 Lead Times
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 redesign--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&t) resources, however, allow redesign of only a few models per year. ‘iajor
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 recertification for air emissions when redesign for noise purposes
takes place.
Based on this information the following lead times are felt to be achiev-
able by major manufacturers, consistent with orderly redesign of an extensive
product line (years from promulgation):
Regulatory Level (SAE J331a)
86 dB 83 dB 80 dB 78 dB 75 dE
Street: Straight forward change -- 1 2 4 6
Major model change -- 4 6 10
Off-Road: Straight forward change 1 2 4 6
Major model change - — 4 6 10
6-14
-------
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 nil ght be achievable at
considerably increased R&D costs:
Regulatory Level (SAE J331a)
86 dB 83 dB 80dB 78 dB 75 dB
Street: Straight forward change -— -- 1 3 5
Major model change -- -- 3 5 7
Off-Road: Straight forward change 1 2 3 5
Major node] change -- 3 5 7
Different manufacturers, of course, have different lead time require-
ments. oise levels of current models (particularly the mechanical contri-
butions), available funds for R&D, size of product line, and familiarity 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 noise
levels of -londa’s current product line would probably allow somewhat shorter
times. riarley-Davidson, Can-Am and the European manufacturers would all be
severely tested to meet the same tine schedule as the major Japanese manu-
facturers, for a variety of reasons relating to unhlue 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 r’Joise Levels
niost manufacturers supplied limited data on experience with motorcycle
noise levels during mileage and time accumulation. Several engineering
reasons were discussed as to why motorcycle noise levels ought to decrease
with usage, at least at first. After the initial breakin 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 noise level deterioration occurs, depending on climate and
operati rig 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 nufflers that reflect
exhaust gases into but not througn the fibrous elements. Some manufacturers
specify repl cerient of fiorous elements or replacecient of the exhaust system
when deterioration occurs At least one ianufacturer supplies free replace-
nient fioerylass for his mufflers.
6-15
-------
In general, manufacturers supplied no engineering reasons why a properly
maintained and operated motorcycle should experience significant noise ernis-
sion 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.
6.8 Relationship to Air Emission Control
A number of manufacturers expressed serious concerns that at strict
levels of air emission controls there may be a significant tradeoff 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 perforifiance.
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 noise 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 noise 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 wit i
a corresponding adverse impact on air emissions.
6.9 Technology to Achieve Noise Levels
eased 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 SAE J331a test procedures. As discussed in Section 3, the
F-76a test procedure is felt to be statistically equivalent to SAE ‘J331a
across a broad range of motorcycles although individual models may vary up or
down by several dB. The manufacturer—supplied information was based on
several models of each of the caanufacturer’s lines. The SAE J331a and F—76ä
noise levels of each of the models used for these purposes were compared to
determine whether these vehicles represented anomalous cases in the
SAE J331a/F—76a relationship. Of 15 models used for technology and Costing
purposes, ten showed differentials of less than 2 d , one showed a di fferen...
tial of 2 dB, and four showed differentials of 3 di3. However, the models
displaying differentials of 2 dB 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 SAE 333 1a
is translated into a study level specified in terms of F-76a.
6-16
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Table 6—5
DETERIORATION OF MOTORCYCLE NOISE LEVELS
Model Deterioration (dB) Mileage
a 2-4 10,000
b +1 6,250
c 1 1/2 6,250
d +1 (peak +2) 6,250
e 0- 6,250
f right side: 0 6,250
left side: +1 6,250
g-k (muffler only, _0.33* to -1.6/6.250 mi up to 19,000
5 models)
1 -1 1/2 (+1; —1/2) 7,160
m -1 1/2 (+1/2) 3,240
* Ai Iative ffti ber indicates a reduction in noiseTeveT
Source: Manufacturer Confidential Data
6—17
-------
SECTION 7
COSTS OF COMPLIANCE
-------
SECTION 7
COST OF COMPLIANCE
7.1 Unit Cost Increases
In complying with the motorcycle noise regulation, manufacturers will
experience increased costs of manufacturing (production) as well as the costs
of research and development, tooling, and testing/certification. This In-
crease in costs will lead to increases in the unit cost (price) of new motor-
cycles. The price of new replacement exhaust systems will also increase for
similar reasons.
Unit cost increases are expected to vary with the type (function) and
size category of motorcycle, and the stringency of the applicable noise
standard itself. The most significant difference in compliance costs will
appear when vehicles, requiring relatively “straight forward” model changes,
are compared with those requiring “major” model changes.
Model changes considered straight forward- include increasing muffler
volume, adding lining to the air-intake system, or stiffening fins and webs of
the engine casing. Major model changes include the use of any noise control
techniques that require extensive R&D, substantial model redesign and pro-
duction tooling modifications, or significant Increases in unit manufacturing
costs. A more complete listing of motorcycle noise control techniques Is
provided In Table 7-1. These were cited by manufacturers as ones necessary to
meet the lower (more stringent) study levels.
There is a high degree of uncertainty as to which motorcycle models (and
for which manufacturers) major changes will be necessary. As a result, two
cases were analyzed; (1) the nominal (expected) case, and (2) the worst case.
With some assumptions, data from manufacturers (including current motorcycle
noise source data) were used to estimate the fraction (expressed in percent)
of motorcycle production requiring major model changes at various regulatory
levels. The results for the two cases are presented in Table 7-2.
For Street motorcycles, the percentages in Table 7—2 apply to all size
categories above 100 cc (no major model changes are expected below 100 cc)
For off-road motorcycles, however, different percentages apply to different
size categories. This Is due to the limited use to which liquid cooling has
been used for off-road motorcycle engines and the fact that virtually all such
engines are single cylinder. Larger off-road motorcycles are expected to
require major model changes (4—stroke conversions) at higher regulatory levels
than smaller off-road types. The estimated distribution of percentages of
major model changes for off-road motorcycles are shown In Table 7-3 (worst
case percentages are In parentheses).
By using the estimated percentages for major model changes In Tables 7-2
and 7-3, the nominal and worst case total unit cost Increases can be calcul-
ated once the Individual cost elements (e.g., for manufacturing, R&D, tooling,
testing and compliance) are known for each vehicle type and displacement
category. Total costs are sumarized in Table 7-4. Further aspects of total
unit costs and cost element breakdowns are given In SectIon 7.1.1.2.
7-1
-------
Table 7—i
NOISE CONTROL TECHNIQUES
EXHAUST SYSTEM INCREASE MUFFLER VOLUME
CROSS CONNECTION
MODIFY INTERIOR
SOUND ABSORPTION LINING
INCREASE SHELL THICKNESS
CONSTRUCT DOUBLE WALLS
ISOLATION MOUNTING
AIR INTAKE INCREASE VOLUME
SYSTEM MODIFY INLET
MODIFY INTERIOR
ADD SOUND ABSORPTION LINING
INCREASE WALL THICKNESS
DOUBLE WALLS
SHIELD INLET
REDUCE INLET AREA
MECHANICAL/DRIVE STIFFEN/DAMPEN FINS AND WEBS
SYSTEM 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 VALVE CLATTER (4-STROKE)
INCREASE FLYWHEEL/CAMSHAFT
MODIFY CLUTCH
MODIFY GEARS/TRANSMISSION
TIGHTEN DRIVE CHAIN
MODIFY FRAME
ISOLATE CHAIN COVER
LOWER ENGINE SPEED
REDUCE SPECIFIC HORSEPOWER
MAJOR MODEL CONFIGURATION CONVERT 2-STROKE TO 4-STROKE
CHANGES (REPRESENTATIVE LIQUID COOLING
EXMPLES) ADD HYDRAULIC TORQUE CONVERTER
CONVERT TO SHAFT DRIVE
ENCLOSE/COVER ENGINE
7-2
-------
Table 7-2
ESTIMATED PERCENTAGE OF STREET MOTORCYCLES
REQUIRING
MAJOR MODEL CHANGES
80 dB
100% (100%)
50% (100%)
0% (100%)
0% (0%)
10% (50%)
Level (A-weighted)
78 dB
100% (100%)
100% (100%)
100% (100%)
0% (100%)
50% (100%)
REGULATORY LEVEL
(SAE J331a not-to-exceed)
FRACTION OF MOTORCYCLE PRODUCTION
- REQUIRING MAJOR MODEL CHANGES
NOMINAL (EXPECTED) CASE WORST CASE
86dB
0%
0%
83dB
0%
0%
80dB
10%
50%
78
dB
50%
100%
75
dB
90%
100%
Table 7-3
ESTIMATED PERCENTAGES OF 0FF-ROAD MOTORCYCLES
REQUIRING
MAJOR MODEL CHANGES
Regul atory
Displacement Category (cc )
350 and above
170—349
100-169
99 and below
Overall (sales weighted)
7-3
-------
Table 7—4
PROJECTED MOTORCYCLE TOTAL UNIT COST INCREASES
FOR VARIOUS REGULATORY LEVELS (1978 dollars)
TOTAL UNIT COST INCREASE
PRODUCT CLASSIFICATION REGULATORY LEVEL (SAL J331a)
86 dB 83 dB 80 dB 78 dB 75 dB
NOMINAL (EXPECTED) CASE —_______________
Street—Legal
99 cc and Below 0 2 2 19 50
100 - 169 cc 0 6 18 74 145
170 - 349 c 0 15 50 129 237
350 - 749 cc 0 19 56 152 287
750 cc and Above 0 22 71 175 321
Average street-legal 0 16 49 133 221
Off-Road
99 cc and Below 0 2 2 19 *
100 - 169 cc 0 6 15 95 *
170 - 349 cc 6 20 76 155 *
350 - 749 cc 6 23 127 185 *
Average off-road 0 8 28 74 *
Fleet Average 0 14 43 117 *
WORST CASE
Street-Legal
99 cc and Below 0 2 2 19 50
100 - 169 cc 0 6 63 147 203
170 - 349 cc 0 15 96 180 246
350 - 749 cc 0 19 112 210 297
750 cc and Above 0 22 130 247 332
Average street-legal 0 16 99 192 223
Off - Road
99 cc and Below 0 2 2 19 *
100 - 169 cc 0 6 62 147 *
170 - 349 cc 6 20 123 185 *
350 - 749 cc 6 23 151 214 *
Average ofF-road 2 18 50 94 *
Fleet Average 0 14 86 166 *
fnT ff j i I 7áiTab1 é
7-4
-------
The methodologies used to compute individual cost elements are similar
with the exception of the testing/certification element. Generally, R&D,
tooling, and testing/certification costs tend to be uniform for a given regu-
latory level for all motorcycle sizes. The manufacturing cost increases
however, tend to become higher with increasing motorcycle size and are higher
for off-road otorcycles than street types. Manufacturing costs account for
between 60 percent and 70 percent of total unit cost.
7.1.1 Manufacturing Unit Costs
Manufacturing unit cost increases are those costs directly related to
the use of noise control techniques that impact fabrication and assembly.
As seen in Table 7-1, they generally relate to the exhaust, air-intake or
mechanical -drive systems.
7.1.1.1 i’ianufacturer Estimates
Each major manufacturer supplied EPA with estimates of manufacturing
unit cost increases for specific models to meet specified study levels (not-
to—exceed standards). They made the major motorcycle model distinctions and
their data were based on the SAE J331a test procedure.
Each manufacturer emphasized that most estimates at the lower levels
were based on engineering judgment alone, and not on operational prototype
models. They indicated that there was no guarantee that individual techniques
cited would achieve the specified study level . Manufacturers addressed
different ultimate levels of control depending on their assessment of feasi-
bility or ability to judge the effectiveness of individual techniques.
Manufacturer estimates are sumarized in Figure 7—1.
Manufacturers also provided cost estimates for various discrete steps in
reductions in exhaust, air—intake and mechanical/drive sources. Figures 7-2,
7—3 and 7-4 show costs associated with each of the subsources, where avail-
able.
Discussion of Data
There are a number of explanations for the scatter shown in Figure 7-1:
(a) In general, costs increase with motorcycle size, because noise generating
capability tends to increase with size, and the costs of affected components
(e.g., exhaust systems, mechanical components) increase with size.
(b) Since subsource noise level contributions differ widely from model to
model (see Section 6) the techniques required to meet specified levels vary
considerably.
(c) Since there are a wide variety of techniques which can be utilized in
reducing the noise 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.
7—5
-------
Costs associated with the reduction of exhaust system noise levels are
shown in Figure 7—2. Again the large scatter in data indicates that for some
exhaust systems, large reductions in noise 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 749 cc category, a
reduction in exhaust noise level (A-weighted) from 82 dB to 70 dB was pro-
jected by the manufacturer to increase manufacturing costs by $60. Almost
all of the techniques listed for exhaust systems in Table 7-i. were used to
achieve the reduction in this case.
Air intake noise 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 dB
78dB $3.0
76dB $8.0
74 dB $15.0
/2 dB $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.
7.1.1.2 Generalized and Independent Estimates
The manufacturer-supplied data in the previous section referred to
various specific motorcycle models and noise control 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 esti-
mated the cost of individual techniques for comparison with the manufacturer..
supplied data. This independent analysis was based on information gained in
interviewing personnel familiar with the machining, costing, welding and other
production processes involved. However, these estimates must be considered
gross engineering judgments because of the difficulty in predicting the noise
reducing effectiveness of the techniques involved. This same problem Is
encountered by motorcycle manufacturers and, in general, the independent
estimates were in agreement with the data supplied by manufacturers. Conse-
quently, these estimates were used in developing generalized estimates.
For exhaust and air intake modifications, a baseline was established for
the cost elements of representative systems, and reasonable cost ranges were
developed for each technique and its associated cost elements. Direct cos
estimates were made for appropriate noise control techniques affecting
7-6
-------
90 89 88
85848382 8 807978717675747372 lldB
REGULATORY LEVEL (SAE J331a, ClIP)
FIGURE ?-1 MANUFACTURING UNIT COST INCREASE VS. REGULATORY LEVEL (MAI’1UFACTURE -SUPPLIEU DATA)
- .4
I-
I - .
— 4
z
-S
I -,
I-
C-)
=
0
-------
-j
-J
Q
LLI
V)
LU
F-
‘I)
L)
I—
I-
(-)
EXHAUST SYSTEM NOISE LEVEL
FIGURE 7-2 EXHAUST SYSTEM MANUFACTURING UNIT COST INCREASES VS.
NOISE LEVEL REDUCTION (MANUFACTURER-SUPPLIED DATA)
60
55
50
45
40
35
30
25
20
78 77 76
-------
V)
1
-J
‘I )
I-
C.)
I-
I —
C.)
FIGURE 7-3
IWTAKE SYSTEM NOISE LEVEL
INTAKE SYSTEM MANUFACTURING UNIT COST INCREASE VS.
NOISE LEVEL REDUCTION (MANUFACTURER—SUPPLIED DATA)
85848382 8 8O 7978 7776 75747372 fl 706968 67dB
-------
FIGURE 7-4
72 71 70
M [ CHAtilCAL/URIVE NOISE LEVEL
MECHANICAL/DRIVE MANUFACTURING UNIT COST INCREASE VS.
NOISE LEVEL REDUCTION (MANUFACTURER—SLJPPLIEi) OMTA)
220
160
140
‘r)
—3
-J
N—
LL
W
L)
-z
I-
C.,)
C-)
I-
L)
120
100
80
60
20
0
83
U 2-STROKE
• 4-STROKE
82 81 80 79 78 77
76
*DENOTES MAJOR
MODEL CHANGE
-350-
749
cc
75 74 73
-------
mechanical/drive components. Independent cost estimates for exhaust system,
air-intake system and mechanical drive system techniques are summarized in
Tables 6, 7 and 8 respectively.
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 repre-
sentative 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 750 cc and above category is provided below in Table
7—5.
Table 7-5
LIQUID COOLING: Street Motorcycle, 750 cc 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
The basic cost elements were selected and scaled according to their
estimated relationships with inotorc,ycle size, relative effectiveness of the
techniques, and the degree of noise attenuation required. An example of the
technique used is shown in Table 7-9 using 1975 dollars . This procedure was
followed for each motorcycle category, regulatory design levels, and for
both straight-forward and major model changes as applicable.
The independent estimates of manufacturing unit cost increases attri-
butable to meeting not-to-exceed regulatory levels for all specific product
categories are summarized in Table 7—10.
These estimates were derived by using the methodology described in
the previous section. The analysis utilized tfle assumptions shown in Table
6-2 for the technology required at each study level.
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 meeting noise emission standards more stringent
than 82 dB, at the same cost (up to $80 depending on engine size).
In the Independent cost estimate very small differences were predic-
ted in cost impacts between motorcycles with 2-stroke and 4—stroke engines,
* Includes welding nachiilng, and assembly.
7-11
-------
Table 7-6
EXHAUST SYSTEM NOISE REDUCTION TECHNIQUES AND ESTIMATED COSTS
(INDEPENDENT EST IMATES)
AFFECTED MANUFACTURERS UNIT COST
COMPONENTS INCREASES (1978 DOLLARS)
SPECIAL AND COST UNDER 100- 170- 350- 750- COST VARIABILITY
TECHNIQUE APPLICABILITY EL [ MENTS 100 cc 169 cc 349 cc 749 cc Above FACTORS COMMENTS
INCREASE MUFFLER IJFFLER SHELLS & 1-2 1—3 1-4 1-5 1-6 DEGREE OF VOLUME GENERALLY
VOLUI’1 FINISH (CHROME. INCREASE PRACTICAL
PAINT PRODUCT CLASS LIMIT -
1O0 INCREASE
INSTALL CROSS-PIPES DUAL EXHAUST HEADERS N/A N/A N/A 10 12 LABOR
BETWEEN HEADERS SYSTEM ONLY CROSS PIPES INTENSIVE
—4
MODIFY HEADER
N.) INTERCONNECTIONS MULTI-CYLINDER HEADER PIPES N/A N/A N/A LABOR
INTENSIVE
(COLLECTIVE MUFFLERS) MOTORCYCLES COLLECTION BOXES
4 into 1 14 14
4 into 2 ONLY 14 14
3 into 1 11 11
2 into 1 7 7
MODIFY INTERIOR ASSEMBLY 1-4 1—8 1—12 1-14 1-16 DEGREE OF GENERALLY
CORE PIPES MODIFICATION IDLE COMPLEX
BAFFLES PRODUCT ASSEMBLY
REACTIVE CLASSIFICATIONS
CHAMBE RS
ADD SOUND ABSORP— LINING MATL 1-3 1—3 1—4 1-5 1-7 TYPE OF LINING
lION LINING LINING HOLDERS. MATERIAL
SCREENS. ETC. COMPLEXITY OF
INSTALLATION
THICKEN/REINFORCE PIJFFLER SHELL 1-8 1-10 1-12 1-14 DEGREE OF THICK-
SHELL MATERIAL REINFORCEMENT NESS INCREASE
HARDWARE DEGREE OF VOLUME
-------
Table 7-7
AIR INTAKE SYSTEM NOISE AND REDUCTION TECHNIQUES AND ESTIMATED COSTS
(INDEPENDENT ESTIMATES)
AFFECTED MANUFACTURERS UNIT COST
COMPONENTS INCREASES (1975 DOLLARS)
AND COST UNDER 100— 170- 350- 750- COST VARIABILITY
TECHNIQUE ELEMENTS 100cc 169cc 349cc 749cc Above FACTORS
INCREASE VOULME INLET DUCTING 1-2 1—2 1—2 1—3 1-3 OECRLASE OF VOLUME
AIR CLEANER INCREASE
BODY PRODUCT CLASS
FI3DIFY INTAKE INLET DUCTING 1—3 1-3 1-6 1-6 1-7 DEGREE OF
INLET MODIFICATION
PRODUCT CLASS
1t DIFY INTERIOR ASSEMBLY
BAFFLES 1-5 1-5 1—6 1-6 1-10
SILENCERS
ADD SOUND ABSORPTION — 1 1-2 1-2 1—3
LINING
INCREASE MATERIAL AIR CLEANER — 1-3 1—4 1-6 1-7
THICKNESS BODY
CONSTRUCT DOUBLE AIR CLEANER — — - - - NOT USED IN COST
WALLS BODY ANALYSIS
SHIELD INLET INLET OPENING — - - - - NO COST IMPACT
REDUCE INLET INLET OPENING — — - - - NO COST IMPACT
AFEA
-------
TECUN IQUE
STIFFER FINS MD CASE WEBS
CHANGE FIN SHAPES
ISOLATE/RE INFORCE
COMPONENTS
THICKEN/REINFORCE CASE
COVERS
INCREASE LUBRICATION
MODIFY P1 STON/CYL INDER
REDUCE TOLERANCES/IMPROVE
FINISH
MODIFY BEARINGS
MODIFY ENGINE TIMING AND
DRIVE BELTS/CHAINS
REDUCE VALVE CLATTER
INCREASE FLYWHEEL MASS
MODIFY CRANK SHAFT/CAN SHAFT
MODIFY CLUTCH
MODIFY GEAR/TRANSMISSION
TIGHTEN DRIVE CHAIN
ENCLOSE DRIVE CHAIN
MODIFY FRAME
BECAUSE OF SPECIAL APPLICABILITY
APPLICATION
RUBBER OR METAL DOWELL BETWEEN
FINS
MODIFY DESIGN
ADD GASKETS, BURNINGS, ETC.
MODIFY ENGINE, GEAR. CRANKCASE
COVERS
INCREASE PRESSURE LUBRICATION
MODIFY PISTON/CYLINDER DESIGN
AND CLEARANCE
REDUCE TOLERANCES, IMPROVE
FINISH OF MACHINED PARTS
MODIFY BEARING AREA, MATERIAL
CONVERT FROM CHAIN DRIVE TO
HI-YLI OR OTHER TYPE
USE HYDRAULIC LIFTERS ON
4-STROKE ENGINES
CRANKSHAFT FLYWHEEL
MODIFY CRANKSHAFT DESIGN
USE OF HELICAL GEARS IN-
STEAD OF SPUR GEARS
INSTALL, MODIFY IDLER ARMS
INSTALL STEEL CASE
REDESIGN, INSULATE FRAME
—
2
2
1—6
1—10
1-4
1—15
—
2
2
2
2
1
1
1
1
1
—
1—2
1—2
1—3
1—3
2
2
2
2
4
5
6
6
1
1
1
1
1
—
5
8
9
10
— 6 9 10 11
— — - 2 2
GENERALLY NO COST
TECHNICAL EFFECT—
TIVENESS
Tab’e 7-8
‘fCHANICAL NOISE REDUCTION TECHNIQUES AND APPROXIMATE COSTS
(INDEPENDENT ESTIMATES)
APPROXIMATE MANUFACTURING UNIT
INCREASE (1975 DOLLARS)
UNDER 100- 170— 350—
_________________________________ 100 cc 169 cc 349 cc 749 cc
1 1 1 1
COST
750—
Above
1
COST
VARIABILITY
FACTORS COMMENTS
NO COST IMPACT
NO.OF COVERS DEGREE
OF MODIFICATION
NOT USED IN COST
ANAL VS IS
NOT USED IN COST
ANALYSIS
NOT USED IN COST
ANALYSIS
SHOULD HAVE MINI-
MAL COST IMPACT
-------
Table 7-9
MANUFACTURING COST INCREASE ESTLIATES (1975 DOLLARS )
SIZE: 170 - 349 cc CHANGE CATEGORY: STRAIGHT FORWARD
MODEL CHANGE
NOISE CONTROL TECHNIQUE COST
OVERALL NOISE LEVEL (dB) 86-83 dB 80 dB 78 dB
EXHAUST 75 dB 73 dB 70 dB
Increase muffler volume 1.0 2.0 3.0
Install cross pipes between mufflers
Modify header interconnections
Modify interior core 1.0 2.0 5.0
Add sound absorption lining 1.0 2.0
Increase shell material thickness 3.0
Construct double walls
Add elastic components
SUBTOTAL $2.0 $6.0 $13.0
AIR INTAKE (dB) 75 dB 73 dB 70 dB
Increase volume 1.0 1.0 2.0
Modify intake inlet 1.0 2.0
Modify interior core 1.0 1.0 2.0
Add sound absorption lining i.o 1.0
Increase material thickness i.o 2.0
Construct double walls
Shield inlet
Add/modify plenum chambers
SUBTOTAL $2.0 $5.0 $9.0
MECHANICAL (dB)
Stiffen fins and case webs i.o 1.0
Change fin shapes
Isolate/reinforce components 2.0 2.0
Thicken/reinforce case covers 3.0 5.0
Increase lubrication 2.0
Modify piston/cylinder i.o
Reduce tolerances/improve finish 2.0
Modify bearings 2.0
Modify timing belt/camshaft
Reduce valve clatter (4-stroke)
Enlarge flywheel 1.0
Modify crankshaft
Modify (damp) clutch
Modify gear/transmi ssion
Tighten drive chain
Enclose drive chain
Modify frame
MAJOR MODEL CHANGES:
Convert 2-stroke to 4-stroke
Use liquid cooling
End ose/cover engine
Add hydraulic torque converter
Convert to shaft drive
Reduce engine RPM
SUBTOTAL $6.0 $16.0
TOTAL MANUFACTURING COST INCREASE $4.0 $16.0 $38.0
7_ic
-------
Table 7—10
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPEN .)ENT ESTIMATE (1978 DOLLARS)
MANUFACTURING UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
PRODUCT CLASSIFICATION 86 dB 83 dB 80 dB 78 dB 75 dB
STRAIGHT FORWARD “CHANGES”
Street-Legal
99 cc and Below 0 0 0 0 o
100—169 cc 0 3 9 30 72
170-349 cc 0 5 19 44 108
350-749 cc 0 9 23 61 144
750 cc and Above 0 12 35 72 167
Off-Road
99 cc and Below 0 0 0 9 *
100-169 cc 0 3 10 30 *
170—349 cc 5 10 23 49 *
350—749 CC 5 13 29 66 *
MAJOR MODEL CHANGES
Street-Legal
100-169 CC * * 53 74 105
170-349 cc * * 64 88 140
340-749 cc * * 93 118 191
753 cc and Above * * 119 155 226
Off-Road
100-169 cc * * 57 74 *
170—349 cc * * 71 93 *
350-749 cc * * 99 122 *
Tr fó thàt •i no t d
7-16
-------
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 were considered equivalent in the independent cost
analysis. Note also that no major model changes were forecasted for rnotorcy—
des under 100 cc in size, for the following reasons: (1) none of the manu-
facturers indicated that models in this category would require major redesign
to meet specified regulatory levels; and (2) the existing noise levels of
motorcycles in this category are relatively low.
A breakdown of baseline independent cost estimates in terms of exhaust,
air—intake, and mechanical components is shown in Table 7—11 using 1975
doll ars.
These nunters were then modified for nominal and worst cases by the
estimated percentage of major model changes required for each regulatory
level (refer to Table 7-12). The resultant costs were included in the pro-
jected total unit cost increase (refer to Table 7-4), although they were
adjusted to 1978 dollars based on average price increases for motorcycles
between these years.
7.1.2 Research and Development Costs
Total unit cost increases listed in Table 7-4 include R&D costs incurred
in order to comply with noise standards.
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 costs on unit cost is particularly difficult to
determine because of variances in the sizes and characteristics 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’ 1 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 avaiIab1 resources and personnel; and dif-
ferences in cost accounting policies.
Impacts will also depend on program variables. For example, the degree
of noise reduction required for each class of motorcycle will determine
whether “straight-forward’ 1 or major model changes are required to comply with
regulatory levels. Estimates for unit cost increases attributable to amor-
tized R&D for these two types of changes were supplied by manufacturers.
These data were assessed for reasonableness, and used to derive unit cost
increases. Again, these estimates were modified by the probabilities asso-
ciated with straight-forward and major model changes in the nominal and worst
cases.
The generalized estimates in Table 7-13 for Category I manufacturers
(manufacturers that produce 100,000 units or more annually) were modified
by two factors to derive the composite (weighted) average R&D unit cost
increases for all manufacturers, shown in Table 7-14. The two factors con-
sidered are: (1) approximately 86% of all motorcycles sold in the U.S. are
manufactured by Category I Tianufacturers, and (2) R&D unit costs for Category
7—17
-------
Table 7-11
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS —
BASELINE INDEPENDENT ESTIMATE (1975 DOLLARS)
UDEL DESCRIPTION REGULATORY LEVELS* (dB) MANUFACTURING COST INCREASE
SIZE FUNCTION TEST OVER- EX- AIR ECFl/ CRANGE**
CATEG. PROC. PLL RAUST INTAKE DRIVE ASS.
(cc) 0 0 EX IU MID (0) (EX) (IN) (MID)
750 and Street— SAE 3331a 86 83 15 75 75 10 6 4 0 SFMC
Above Legal 80 72 72 73 30 13 10 7
78 70 70 71 63 24 16 23
75 67 61 68 146 52 30 64
350-749 Street- SAE J331a 86 83 75 15 15 8 4 4 0 SFMC
Legal 80 72 72 73 22 9 6 7
78 70 70 71 55 18 12 25
75 67 67 68 129 44 25 60
110—349 Street- SAE J331a 86 83 75 75 75 4 2 2 0 SFMC
Legal 80 72 72 73 16 5 5 6
78 70 70 71 38 13 9 16
75 67 67 68 92 27 20 45
100-169 Street- SAE J331a 86 83 75 75 75 2 1 1 SFMC
Legal 80 72 72 13 8 3 4 1
78 70 70 71 25 11 8 6
75 67 67 68 61 20 14 27
99 and Street— SAE J331a 86 78 71 71 69 7 3 4 0 SFMC
Below Legal 75 67 67 69 17 9 8 0
* Regulatory not—to-exceed noise level applicable to overall (0) level. Subsources are design level.
** SFMC — Straight Forward Model Change.
tlD - Major Model Change
-------
Table 1—11 (continued)
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS —
BASELINE INDEPENDENT ESTIMATE (1975 DOLLARS)
I1 DEL DESCRIPTION 1 GULATORY LEVELS* (dB) MANUFACTURING COST INCREASE
SIZE FUNCTION TEST OVER- EX- AIR I [ CHf CHANGE**
CATEG. PROC. ALL HAUST INTAKE DRIVE CLASS.
(cc) 0 0 EX IU MID (0) (EX) (IN) ( MID )
350-749 Off-Road SAE J331a 89 86 82 82 75 4 2 2 0 SFMC
83 75 75 75 12 6 6 0
80 72 72 73 26 11
78 10 70 71 59 20 14 25
‘C’ 110-349 Off-Road SAF J331a 89 86 82 82 75 4 2 2 0 SFMC
83 75 75 75 8 4 4 0
80 72 72 73 20 7 7 6
78 70 70 71 42 15 11 16
100-169 Off—Road ME J331a 86 83 75 75 75 2 1 1 0 SF1IC
80 72 72 73 8 3 4 1
78 70 70 71 25 11 8 6
99 and 0ff-Road 80 78 71 71 69 7 3 4 0
Below 75 67 67 69 17 9 8 0
Regulatory not—to-exceed noise level applicable to overall (0) level. Subsources are design level.
** SFMC - Straight Forward Model Change.
I’ 1D - Major Model Change
-------
Table 7—11 (Continued)
MANUFACTURING UNIT COST INCREASES VERSUS REGULATORY LEVELS -
BASELINE INDEPENDENT ESTIMATE (1975 dollars)
M3DEL DESCRIPTION REGULATORY LEVELS* 1DB) MANUFACTURING COST INCREASE
SIZE FUNCTION TEST. OVER— LX- AIR l’ [ CH/ CHANGE**
CATEG. PROC. LL HAUST INTAKE DRIVE CLASS.
(cc) 0 0 EX IU MID (0) (EX) (IN) (MID)
750 and Street- SAE J331a 86 83 75 75 75 10 6 4 0 TIE
Above Legal 80 72 72 73 103 13 10 80
78 10 70 71 135 24 16 95 80
75 67 67 68 198 52 30 116 dB
350-749 Street- 86 83 75 75 75 8 4 4 0 IIIC
Legal 80 72 72 73 85 9 6 70
78 70 70 71 108 18 12 78 80
75 67 67 68 174 44 25 105 dB
170—349 Street— SAE J331a 86 83 75 75 75 4 2 2 0 *IC
Legal 80 72 72 73 55 5 5 45
78 70 70 71 74 13 9 52 80
75 67 67 68 118 27 20 71 dB
100-169 Street— SAE J331a 86 83 75 75 75 2 1 1 0 T4IC
Legal 80 72 72 73 47 3 4 40
78 70 70 71 61 11 8 42 80
75 67 67 68 87 20 14 53 dB
* Regulatory not-to-exceed noise level applicable to overall (0) level. Subsources are design level.
** SFMC - Straight Forward Model Change.
* 10 - Major Model Change
-------
Table 7-11 (Continued)
MANUFACTURING UNIT COST INCREASES VERSUS REGULAiORY LEVELS -
BASELINE INDEPENDENT ESTIMATE (1975 dollars)
t’UDEL DESCRIPTION REGULATORY LEVELS* (dB) MANUFACTURING COST INCREASE
SIZE FUNCTION TEST. t1 ER- LX— AIR 1 [ CH/ CHANGE**
CATEG. PROC. ALL HAUST INTAKE DRIVE CLASS.
(cc) 0 0 EX IU MID (0) (EX) (IN) (M/D)
350-749 Off-Road SAL J331a 89 86 82 82 75 4 2 2 0 T1C
83 75 75 15 12 6 6 0
80 72 72 73 89 11 8 70 80
78 67 70 71 112 20 14 78 dB
170-349 Off-Road SAL J331a 89 86 82 82 75 4 2 2 0 SFMC
83 75 75 75 8 4 4 0
80 72 72 73 59 7 7 45 80
78 67 70 71 78 15 11 52 dB
100-169 0ff—Road SAL J331a 86 83 75 75 75 2 1 1 0 SFMC
80 72 72 73 47 3 4 40
78 70 70 71 61 11 8 42 80
dB
* Regulatory not-to-exceed noise level applicable to overall (0) level. Subsources are design level.
** SFMC - Straight Forward Model Change.
?lD - Major Model Change
-------
Table 7—12
MANUFACTURING UNIT COST INCREASES FUR VARIOUS REGULATORY LEVELS
NOMINAL AND WORST CASES (1978 Dollars)
MANUFACTURING UNIT COST INCREASE
PRODUCT CLASSIFiCATION REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 80 dB 78 dB 75dB
NOMINAL (EXPECTED) CASE
Street-Legal
99 cc and 3elow 0 0 0 9 21
100 - 169cc 0 3 13 52 100
170 - 349cc 0 5 23 67 136
350 - 749cc 0 9 29 90 186
750 cc and Above 0 12 44 113 220
Off-Road
99 cc arid Below 0 0 o 9 *
100 - 169 CC 0 3 10 73 *
170 - 349 cc 5 10 49 93 *
350 — 749 cc 5 13 100 123 *
WORST CASE
Street-Legal
99 cc and E elow 0 0 0 9 21
130 - 169 cc 0 3 35 74 105
170 - 349 cc 0 5 44 88 140
350 - 749 cc 0 9 60 118 191
750 cc and Above 0 12 78 155 226
Off-Road
99 cc and Below 0 0 0 9 *
100 — 169 cc 0 3 57 74 *
170 - 349 cc 5 10 71 93 *
350 — 749 cc 5 13 99 122 *
* Information not available
7—22
-------
II manufacturers (manufacturers that produce less than 100,000 Units per year)
are estimated to be double those of Category I manufacturers.
The second factor is to be expected because total R&D expenses are
allocated over fewer units when estimating costs on a per unit basis. There-
fore the composite weighted average for all motorcycle manufacturers should be
roughly 1.14 times the cost of Category I manufacturers.
Table 7—15 shows nominal and worst case R&D unit costs associated
with different regulatory levels. These values are used in computing total
unit cost increases.
7.1.3 Tooling and Other Manufacturing Equipment Costs
Total unit cost increases in Table 7-4 also include expenditures related
to addition or modification of tooling and other production related equipment.
Generalized cost estimates for Category I manufacturers are summarized in
Table 7-16. Estimates for both straightforward arid major model changes are
provided. The generalized estimates represent an evaluation of trends in-
dicated in manufacturer-supplied data. A liberal (high) estimate of jnit
tooling costs for major model changes was used.
Tooling costs on a unit basis tend to oe considerably higher for Category
II manufacturers (producing 100,000 units per year or less), because fixed
expenses are allocated over fewer units. As in the case of R&D expenses, it
would appear that unit tooling costs for Category II manufacturers are approx-
imately double that of Category I manufacturers.
A composite weighted average for all manufacturers was computed using the
1.14 factor derived for R&D costs. The weighted average is summarized in
Table 7-17. Composite cost estimates for nominal and worst cases are sum-
marized in Table 7-18.
These costs are included in the total unit cost increases listed ii
Table 7—4.
7.1.4 Testing and Certification Costs
For standardized acceleration tests, the basic sound level meter and
accessories required typically cost between $550 and $2,600 in 1975 dollars
(See Table 7-19). A sound level recorder, if necessary, would cost an
addi tional $2,400.
(a) I oving Tests
The test facilities of najor vehicle manufacturers are generally per-
manent installations, and cost at least $225,000 and up. A common alter-
native to setting up permanent facilities is to lease test sites. A typical
facility rental cost would be $100 per day. Based on experience gained in
7-23
-------
Table 7—13
OTORCYCLE uNIT COST INCREASES GENERALIZED COST ESTU4ATE
DUE TO R&D EXPENSES: CATEGORY I MOTORCYCLES MANUFACTURERS
(1978 DOLLARS)
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
TYPE OF CHANGE 86 dB 83 dB 80 dB 78 dB 75 dB
Stral ghtforward
Model Change $1 $2 $9 $16 $24
lajor Model Change * * $37 $41 $49
@ 80 dB (SAE J331a)
Table 7-14
M 0T0RCYCLE UNIT COST INCREASE DUE TO AMORTIZED R&D EXPENSES:
COMPOSITE WEIGHTED AVERAGE FOR ALL MANUFACTURERS
(1978 DOLLARS)
IJTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
TYPE OF CHANGE 86 dB 83 dB 80 dB 78 dB 75 dB
Straightforward
Model Change $1 $2 $10 $19 $28
Major Model Change * * $42 $46 $56
@ 80 d3 (SAE J331a)
Den vation Notes:
1. Available information Indicates that manufacturers with production
volumes less than 100,000 units per year are likely to have unit
R&u costs that are twice (2) that of manufacturers with production
volumes of 100,000 or more units per year.
2. I anufacturers with production vo1u ie 1 ss than 100,000 units per
year sell 14% of all motorcycles sold in the U.S.
7-24
-------
Table 7-15
MOTORCYCLE UNIT COST INCREASES DUE TO AMORTIZED R&D EXPENSES;
NOMINAL (EXPECTED) AND WORST CASES
(1978 DOLLARS)
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 80 dB 78 dB 75 cIB
Nominal (Expected)
Case $1 $2 $13 $33 $53
Worst Case $1 $2 $26 $46 $55
Table 7-16
4OTORCYCLE UNIT COST INCREASES GENERALIZED COST ESTIMATE
DUE TO TOOLING EXPENSES FOR CATEGORY I MOTORCYCLES MANUFACTURERS
(1978 DOLLARS)
MOTORCYCLE UNIT COST INCREASE
TYPE OF CHANGE REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 80 dB 78 dB 75 dB
Strai ghtforward
Model Change $0 $5 $8 $10 $15
Major Model Change * * $35 $38 $43
0 80 dB (SAE J331a)
* Irif atfoñ not avallabli
7-25
-------
Table 7-17
MOTORCYCLE UNIT COST INCREASES DUE TO TOOLING EXPENSES:
COMPOSITE WEIGHTEi) AVERAGE FOR ALL MANUFACTURERS
(1978 DOLLARS)
MOTORCYCLE UNIT COST INCREASE
TYPE OF CHANGE REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 80 dB 78 dB 75 dB
Strai ghtforward
Model Change $0 $6 $9 $12 $17
Major Model Change * * $40 $44 $49
@ 80 dB (SAE J331a)
Table 7-19
MOTORCYCLE UNIT COST INCREASES DUE TO TOOLING EXPENSES:
NOMINAL (EXPECTED) AND WORST CASES
(1978 DOLLARS)
MOTORCYCLE UNIT COST INCREASE
REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 30 dB 78 dB 75 dB
Nominal (Expected) $0 $6 $12 $27 $46
Case
Worst Case $0 $6 $24 $44 $49
* Info rma tio,i noFa vail abTi
7-26
-------
Table 7-19
TYPICAL COST OF SOUND LEVEL METERS AND ACCESSORIES
COMPONENT COST
Type I Sound Level Meter (B&K 2209) $1,706
Microphone 343
Pistonphone 475
Accessories (tripod, windscreen, etc.) 100
$2,624
Type II Sound Level Meter (B&K 2213) $ 354
Acoustic Calibrator 177
Accessories 15
$ 546
Sound Level Recorder (B&K 2306) $2,400
Source: B&K Catalog (prices as of July 1, 1975).
7—27
-------
EPA’s motorcycle test program, the noise levels of approximately 20 motor-
cycles can be measured per eight—hour period, since the initial set-up time is
minimal. The tests require two technicians and a rider, and include six noise
level measurements in each direction.
For an afterruarket exhaust system manufacturer, considerably more
time would be required to transport motorcycles to leased test facilities,
to set-up the test site, and to exchange exhaust Systems as required.
Again, based on EPA ’s test experience, the noise levels of approximately
eight exhaust system configurations can be measured in an eight-hour period.
These costs are delineated in Tables 7-20 A, B, C, D, E, F.
(b) Stationary Tests
Stationary tests are the simplest tests to administer and require
minimal facilities. In addition, the actual testing time is almost
negligible. The two basic elements for estimating testing costs are the
measurement rates and the number of personnel required. Costs can be computed
by usfng an appropriate labor rate combined with the number of tests con-.
ducted.
Estimated testiny costs for three motorcycle manufacturers are summarized
in Table 7—20. An EPA estimate appears in Table 7—21.
Although 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 equipment amorti-
zation over a four-year period. A breakdown of the manufacturer estimated
costs using 1978 dollars follow:
Cost on
Cost Element Cost Annual Basis Unit Cost
Equipment $350,000 $ 87,500 0.32
Test and Administration $350,000 350,000 1.30
Cost
Subtotal 1.62
Assuming that unit costs for smaller manufacturers are higher, a reason-
able estimate for the composite weighted average for all motorcycles is $1.75
per unit. In addition, Harl 1 y Davidson estimates labeling would add approxi-
mately $0.5 to unit costs. Compliance testing and certification costs
would therefore add approximately $2.25/unit costs, and this value is
included in total unit cost increases (refer to Table 7-4).
L AMF/Harley-Davidson’s reply to Exhaust Emission Notice of Proposed
Rulemaking, January 30, 1976
7-28
-------
Item
Revenue froiii exhaust systems
No. of exhaust system models
No. of different muffler cores
No. of cores requiring R&D at
the 83/86 dB level
No. of cores requiring R&D at
the 80/82 dB level
No. of new motorcycles added
to product line coverage
each year
No. of current year motorcycles
for which exhaust systems are
offered
Cumulative percenta je of revenues
froi mufflers for regulated
motorcycles
in 1st year:
in 2nd year:
in 3rd yedr:
Table 7-20 A
ASSUMPTIONS USED TO DESCRIBE A LARGE AFTERMARKET
MANUFACTURER AND A SMALL AFTERMARKET MANUFACTURER
Large Manufacturer Small Manufacturer
1,000K 200K
126 25
13 4
5 2
10 4
5 2
30 12
16% 16%
32% 32%
48% 48%
7-29
-------
Table 7-20 B
EXHAUST SYSTEM MANUFACTURER’S, COSTS FOR R&D BY THE FEDERAL PASS—BY
TEST AND BY THE F50 STATIONARY TEST
Stationary
Item Federal Pass-by Test F5O Test
Cost of Redesign of
10 muffler cores:*
Labor $15,500 $11,800
Site 1,300
Motorcycle costs 900 900
Transportation 1,300
Test equipment 300 300
$19,300 $13,000
or about $1900/core or about $1300/core
*Labor for Pass-by Test: one engineer for 3 months @ $20/hr = $10,400; one
day of testing per week for 3 months = 13 days; 2 technicians @ $12/hr
plus one mechanic @ $15/hr plus one driver @ $10/hr for 13 days =
$5,100
Labor for Stationary Test: one engineer for 3 months @ $20/hr = $10,400;
1/2 day of testing per week for 3 months 6 1/2 days; one technician
@ $12/hr plus one mechanic @ $15/hr for 6 1/2 days = $1,400.
Test Site @ $100/day for 13 days = $1,300
Motorcycle Lease: A $90 wholesale exhaust system is exchanged for use of each
motorcycle in the testing. 10 motorcycles @ $90/motorcycle = $900.
Transportation Costs: $10/motorcycle for 10 motorcycles for 13 days = $1,300
Test Equipment: $2624 with a 4 to 5 year life = $600/year divided equally
between R&D testing costs and compliance testing costs.
7-30
-------
Table 7-20 C
YEARLY COMPLIANCE TESTING COSTS FOR A LARGE EXHAUST SYSTEM MANUFACTURER
USING THE FEDERAL PASS—BY TEST (8 EXHAUST SYSTEMS TESTED PER DAY)
30 Exhaust Systems 5 Exhaust Systems
Labor $1,568 (4 days) $392 (1 day)
Site. 400 100
Motorcycle Costs - - --
Transportation 300 50
Administrative Costs (15%) 340 81
Equipment 300 300
$2, U 923
YEARLY COMPLIANCE TESTING COSTS FOR A SMALL EXHAUST SYSTEM MANUFACTURER
USING THE FEDERAL PASS-BY TEST (8 EXHAUST SYSTEMS TESTED PER DAY)
12 Exhaust Systems 2 Exhaust Systems
Labor $ 784 (2 days) $ 392 (1 day)
Site 200 100
Motorcycle Costs
Transportation 120 20
Administrative Costs (15%) 165 76
Equipment 300 300
$1,569 $888
7-31
-------
Table 7-20 0
YEARLY COMPLIANCE TESTING COSTS FOR A LARGE MANUFACTURER USING THE
F50 STATIONARY TEST (16 EXHAUST SYSTEMS TESTED PER DAY)
30 Systems
Labor $ 432 (2 days)
Si te
Motorcycle Cost
Transportation &
Administrative Costs 300
Equipment 300
$1,032
YEARLY COMPLIANCE TESTING COSTS FOR A SMALL MANUFACTURER USING THE
F50 STATIONARY TEST (16 EXHAUST SYSTEMS TESTED PER DAY)
12 Systems
Labor $ 216 (1 day)
Site
Motorcycle Costs
Transportation &
Administrative Costs 120
Equipment 300
$ 636
7-32
-------
Table 7-20 E
AVERAGE YEARLY COSTS OF R&DJ./ AND PV TESTING AFTERMARKET
EXHAUST SYSTEM MANUFACTURERS FOR THE
FEDERAL PASSBY TEST VS. THE F50 STATIONARY TEST
(Passby Test/F50 Test)
Level of Standard Large Manufacturer.?! Small Manufacturer 2 !
83/86 dB for Street/Off-road
Amortized Over the 3 Year Period
R&D $3200/$2200 $1300/$ 900
PV Testing 1600/ 700 1100/ 600
Total 4800/ 2900 2400/ 1500
80/82 dB for Street/Off-road
Amortized Over the Initial 3
$6300/$4300
$
2500/$1700
Year Period
R&D
PV Testing
1600/ 700
1100/ 600
Total
7900/ 5000
3600/ 2300
80/82 dB for Street/Off-road
After InItial 3 Year Period
--
--
R&D
PV Testing
$ 900/$600
$
900/$ 600
Total
900/ 600
900/ 600
L R & D lnclud icos€ of redesign and prototype testing
2. Large manufacturer revenues are assumed to be 1 million
3. Small Manufacturer revenues are assumed to be 200,000
7-33
-------
Table 7—20 F
Average Price Increase of Aftermarket Exhaust System
Due to R&D and PV Testing by the
Federal Passby Test vs. the F50 Stationary Test
(Passby Test/F50 Test)
Level of Standard Large Manufacturer Small Manufacturer
83/86 dB for Street/Off-road
Amortized Over the 3 Year Period
R&D 1.O%/O.7% 2.O%/1.4%
PY Testing O.5%/O.2% 1.7%/o.g%
Total 1.5%/0.9% 3.7%/2.3%
80/82 dB for Street/Off-road
Amortized Over the Initial 3
Year Period
R&D 2.O%/1.4% 3.9%/2.7%
PV Testing O.5%/O.2% 1.7%/O.9%
Total 2.5%/1.6%
80/82
After
dB for
Initial
Street/Off-road
3 Year Period
0
0
R&D
PV
Tot
Testing
al
O.09%/O.06%
O.09%/O.06%
O.05%/O.03%
O.05%/O. 03%
7-34
-------
Table 7-20
ESTIMATED COST OF COMPLIANCE TESTING -
MANUFACTURER SUPPLIED DATA
(1975 DOLLARS)
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 - $400,000 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.
7-35
-------
Table 7—21
ESTIMATE OF ANNUAL TESTING AND
CERTIFICATION COSTS--MAJOR i ANUFACTURER
(1975 DOLLARS)
COST COMPONENT COST
Production Verification 25 models 1 test each
(see enforcement section) 3 persons 1 hr/test 75 hr
Selective Enforcement Audit 3 models 15 vehicles/model
(see enforce;oent section) 3 persons 1 hr/test 135 hr
Label Verification 25 models 30 test each 125 hr
(see enforceiiient section) 2 persons 5 mm/test
Reporting & Administration 250 hr
Total 585 hr At $20/hr $11 ,700
Materials and 4iscellaneous 5,000
Total $16,700
-------
7.1.5 Total Weighted Unit Cost Increases
Total unit cost increases resulting from compliance with noise stan-
dards arise from 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 at various regulatory levels for the
several motorcycle product categories are surnarized in Table 7-4. A break-
down of total unit costs by major cost element is provided in Tables 7-22 and
7—23. As has been indicated, in general, the largest contributor to the unit
cost increase is the manufacturing cost, which typically ranges from between
60 to 70 percent of the total , followed by amortized R&D costs, unit tooling
costs, and the testing and certification costs.
Probable unit cost increases for compliance with the noise emission
standards were determined for all motorcycles that were tested. These costs
were then weighted by the percentage of the total market share for each
manufacturer in each engine displacement class and totaled to obtain unit cost
increases for various regulatory levels of each engine displacement class.
These calculations were made for both street-legal and off-road motorcycles
and for nominal (expected) and worst cases. Refer to Table 7-24 for projected
weighted total unit cost increases for the various regulatory levels.
7.2 Purchase Price Impacts
The impact of cost increases on motorcycle purchase prices is a complex
situation and one which will be determined in the final analysis by free
market interaction between supply and demand. However, some of the cost
scenarios which are likely to occur as a result of the interaction of these
economic forces are presented in this section.
Table 7—25 provides an approximation of the existing price mark—up struc-
ture between ianufacturer and distributor (if any) and 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 support
this estimate. Generally, EPA assumes the worst-case price increase due to an
incremental change in cost is assumed to be 50 percent. However, the impact
on price could range 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.
Representative cases in which four different levels of mark—up could occur are
described following Table 7—25.
Cases I and II would be considered very optimistic, primarily because
they are counter to normal mark-up policies, even for “incremental cost
7-37
-------
Table 7—22
TOTAL UNIT COST INCREASE ELEMENTS:
NOMINAL (EXPECTED) CASE
(1978 DOLLARS)
UNIT COST INCREASE (DOLLARS)
STREET LEGAL, 750 cc
Over
Man facturing Cost
R&D
Tooling (Mfg.
Equi pment)
Compliance Testing
& Certification Cost
Total __________________________________________________
STREET LEGAL, 350-749 cc
Manufacturing Cost
R&D
Tooling (Mfg.
Equipment)
Compliance Testing
& Certification Cost
Total ________________________________________
STREET LEGAL, 170—349 cc
Manufacturing Cost
R&D
Tooling (Mfg.
Equipment)
Compliance Testi ng
& Certification Cost
Total _______________________
STREET LEGAL, 100-169 cc
Manufacturing Cost
R&D
Tooling (Mfg.
Equl prnent)
Compliance Testing
& Certification Cost
Total
86 dB
REGULATORY
83 dB
NOISE LEVELS’
80 dB
(SAE J331a)
78dB 75dB
*
*
12
2
6
44
13
12
113
.33
27
220
53
46
*
2
2
2
2
*
22
71
175
321
*
*
*
9
2
6
29
13
12
90
33
27
186
53
46
2
2
2
2
19
56
152
287
*
5
2
6
23
13
12
67
33
27
136
53
46
*
2
2
2
2
15
50
129
237
*
*
*
3
1
0
13
2
1
52
14
6
100
33
13
2
2
2
2
*
6
18
74
148
1. ot-to-exceiUrègulatory levels.
2. Amortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis.
* Information not available
7-38
-------
Table 7-22 (Cont’d)
TOTAL UNIT COST INCREASE ELEMENTS:
NOMINAL (EXPECTED) CASE
(1978 DOLLARS)
UNIT COST INCREASE (DOLLARS)
IOISE LEVELS 1
_______ 8OdB
STREET LEGAL, 99 cc
BELOW ____
Man facturi ng Cost
R&D
Tooling (Mfg.’ 3
Equi pment)
Compliance Testing
& Certification Cost
Total _________________________________________________
OFF-ROAD, 350-749 cc
Manufacturing Cost
R&D
Tooling (Mfg.
Equ i pinent)
Cosnpl i ance Testing
& Certification Cost
Total ___________ _____
Manufacturing Cost
R&D
Tooling (Mfg.
Equi pinent)
Compi i ance Testing
& Certification Cost
Total ___________ __________________
Manufacturing Cost
R&D
Tooling (Mfg.
Equi pment)
Conipi i ance Testing
& Certification Cost
Total
86 dB
REGULATORY
83 dB
(SAE J331a)
78dB 75dB
0
0
0
0
0
0
0
0
0
9
2
6
21
14
13
*
2
2
2
2
O _
2
2
19
50
5
1
0
13
2
6
100
13
12
123
33
27
*
0
2
2
2
*
6
23
127
185
*
5
1
0
10
2
6
49
13
12
93
33
27
*
*
0
2
2
2
*
6
20
76
155
*
OFF-ROAD, 170-349 cc
OFF-ROAD, 100-169 cc
0
3
10
73
*
0
1
2
14
*
0
0
6
6
*
-
2
2
2
*
0
6
20
95 *
1. Not-to-exceed regulatory levels.
2. Amortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis
* Information not available
-------
Table 7-22 (Cont’d)
0FF-ROAD. 99 cc &
BELOW
Man facturi ng Cost
R&D 3
Tooling (Mfg.
Equl pment)
Compliance Testing
& Certification Cost
Total
TOTAL UNIT COST INCREASE ELEMENTS
NOMINAL (EXPECTED) CASE
(1978 DOLLARS)
UNIT COST INCREASE (DOLLARS)
17 i f to é ceed egulitory1eveTs
2. Amortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis.
REGULATORY NOISE
LEVELS’ (SAE J331a)
86dB
83 dB
80 dB
78
dB
0
0
0
9
0
0
0
2
0
0
0
6
0
2
2
2
0 2
2
19
7-40
-------
Table 7-23
TOTAL UNIT COST INCREASE ELEMENTS
WORST CASE
(1978 DOLLARS)
UNIT COST INCREASE (DOLLARS)
REGULATORY NOISE LEVELS 1 (SAE J331a)
86 dB 83dB 80 dB -- 78 dB 75 dB
STREET LEGAL, 750 cc
OVER
Man facturing Cost
R&D 3
Tooling (Mfg.
Equipment)
Compliance Testing
& Certification Cost
Total ____ ____
STREET LEGAL, 350-749 cc
Manufacturing Cost
R&D
Tooling (Mfy.
Equi pment)
Compi lance Testing
& Certification Cost
Total ___________ _______ _____________ ______
STREET LEGAL, 170-349 cc
Manufacturing Cost
R&D
Tooling (Mfg.
Equipment)
Compliance Testing
& Certification Cost
Total ______________________________ ____ _________
STREET LEGAL, 100-169cc
ilanufacturlng Cost
R&D
Tooling (Mfg.
Equipment)
Compliance Testing
& Certification Cost
Total
0
12
78
155
226
0
2
26
46
55
0
6
24
44
49
0
0
22
2 2 2 2
130 247 332
0
9
60
118
191
0
2
26
46
55
0
6
24
44
49
0
2
2
2
2
0
19
112
210
297
0
0
0
5
2
6
44
26
24
88
46
44
140
55
49
0
2
2
2
2
0
15
96
180
246
0
0
0
3
1
0
35
2
24
74
27
44
105
47
49
0
2
2
2
2
0
6
63
147
203
1. Not to exceed regulatory levels.
2. Azoortized R&D costs on a unit basis.
3. Amortized tooling costs on a unit basis.
7 -41
-------
Table 7-23 (Cont’d)
TOTAL UNIT COST INCREASE ELE 1ENT
W3RST CASE
(1978 Dollars)
UNIT COST INCREASE (JOLLARS)
REGULATORY JOISE
86dB 83dB
LEVELS 1 (SAC J331a)
dOdD 78dB
OFF-ROAD, 350—749 cc
Man factuririy Cost
R&D
Tooling (Mfg.
Equipment)
Compliance Testing
& Certification Cost
Total
0FF-ROAD, 170-349 cc
1anu fac turf ny Cost
R&D
Tooling (‘lfy.
Equipment)
Compliance Testing
& Certilication Cost
Total
OFF-ROAD, 100-169 cc
Manufacturing Cost
R&D
Tooling (Mf .
Equipment)
Compliance Testing
& Certification Cost
Total
0 6
a tory i Ts
2. A iiortized R&D costs on a unit basis.
3. Arnortiz d tooli 13 costs a unit basis.
1
2
26
45
0
6
24
44
0
2
2
2
6 23
5 10
1 2
o 6
O 2
6 20
0 3
o 1
0 0
0 2
71
26
24
93
46
44
2
2
123
185
57
2
21
14
27
44
2
2
82
147
7-42
-------
Table 7-24
PROJECTED WEIGHTED TOTAL UNIT COST INCREASES VERSUS REGULATORY LEVELS
NOMINAL AND WORST CASE
(1978 DOLLARS)
TOTAL
WEIGHTED UNIT COST INCREASE
REGULATORY NOISE LEVELS (SAE J331a)
PRODUCT CLASSIFICATION 86 dB 83 dB 80 dB 78dB 75 dB
NOMINAL (EXPECTED) CASE
99 cc and Below 0 1 1 16 64
100-169 cc 0 1 8 64 138
170-349 cc 0 3 34 102 210
350-749 cc 0 5 30 99 241
750 cc and Above 0 9 47 144 289
Average Street-Legal 0 5 30 100 221
99 cc and Below 0 2 2 18 *
100—169 cc 0 1 35 *
170-349 cc 3 20 76 156 *
350-749 cc 6 23 127 185 *
Average 0ff-Road 1 7 26 60 *
FLEET AVERAGE ___ O 6 29 89 * -
WORST CASE
99 cc and Below 0 1 1 16 64
100-169 cc 0 1 33 117 173
170-349 CC 0 3 63 140 210
350-749 CC 0 5 67 149 241
750 cc and Above 0 9 92 201 289
Average Street-Legal U 5 63 147 226
99 cc and Below 0 2 2 18 *
100-169 cc 0 1 23 54 *
170-349 CC 3 20 122 184 *
350-749 cc 6 23 151 214 *
Average Off-Road 1 7 41 72 *
FLEET AVERAGE 0 6 ____ 57 127 *
f6v ñatforfliot vaTabTë
7-43
-------
Table 7—25
NEW MOTORCYCLE PRICE MARK-UPS
LEVEL
PRICE
CONSENSUS
EST. A.
B. Mark-Up Cum I’iark—Up
New Motorcycle
Manufacturers
6 to 12% -
- - - -
Distributors 1
20% 0-25%
12-15% 0-25% 0-25%
Deal ers
40% 33%
20-25% 33% 20331o 20-66%
Note: 1. Significant price discounting can occur at this level.
Sources: A. International Research and Technology Corporation. ‘ The Iiiipact
of Noise Abatement Standards on the otorcycle Industry.”
3. Manufacturer supplied confidential data.
C. Motorcycle Industry Council, “Manufacturer’s Shipment Reporting
System.”
REPRESEtJTATIVE CASES DEP1CTINt FOUR DIFFERENT 1ARK-UP LEVELS
Price Mark—Up
Case - Factor iditions
l 0.9 This would occur if the manufacturer absorbed
part of the incremental cost increase, and
di stri butors and deal ers reduced thei r mark-
up factors to allow for straight pass-through
of cost increase.
II 1.0 This would occur if nanufacturers, distribu-
tors and dealers passed increased cost
straight through to consumers.
III 1.2 This would occur if manufacturer and distrib-
utors passed costs straight through to dealers
and dealers either used their standard iuark—
up or discounted their prices.
IV 1.5 This would occur if unit cost increase is
marked—up by standard rates at each level.
7-44
-------
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
severely. 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 weighted unit cost increases determined in the cost analysis are
used as the basis of estimating price increases (refer to Table 7—24). In the
nominal case, total weighted unit cost increases are factored by the 1.2 price
mark-up factor derived in the previous section to determine price increases
and in the worst case, total weighted unit costs were factored by a 1.5 price
mark-up factor. The results for the two cases and for each product category
are summarized in Table 7-26, and shown in Figures 7-5 through 7-8. These
price impacts are for regulatory levels as defined by the SAE J331a test
procedure.
The projected average unit price increases for street-legal, off-road,
and all motorcycles for nominal and worst cases are shown in Figures 7-9 and
7—10.
Average 1978 prices for each of the product categories are shown in
Table 7-27. These prices were used as the baseline reference to compute the
relative price increases which are also summarized in Table 7-27.
7.3 Replacement Exhaust System Price Impacts
Using manufacturer-supplied data and an independent estimate, the
purchase price increases expected for 4 into I and 2 into 1 exhaust systems
were calculated and are shown in Tables 7-28, 7-29, and 7-30.
Projected relative price increases for two typical exhaust systems
are sumarized as follows:
Regulatory 4 into 1 2 into 1
Exhaust Exhaust
Level System System
80 dB +21% +26%
78 dB +40% +50%
7.4 ORerational Cost Increases
As discussed in Section 6.3 the principal operational cost increases
associated with lower levels of noise are the impact on fuel economy. Based
on the fuel penalties in Section 6.3.2, the “nominal” and “worst” case esti-
7-45
-------
Table 7-26
PROJECTED MOTORCYCLE PRICE INCREASES
FOR VARIOUS J331a REGULATORY LEVELS
(1978 DOLLARS)1.
PRODUCT CATEGORY
NOMINAL CASE
UNIT PRICE INCREASE
REGULATORY LEVEL (SAE J331a)
86 dB 83 dB 80 dB 78 dB
75 dB
Street-Legal
Fleet Average
99 cc and Below
100 - 169 cc
170 - 349 cc
350 - 749 cc
Average off-road
Fleet r Verage
0 6
O 2 2
O 1 34
4 30 183
9 34 226
1 9 60
35 138
1. 197 ”dollars -- Ba ed o,ôt èd
* Information not available
weighted total unit
cost increases
99 cc and Below
0
1
1
19
77
100—169 cc
0
1
10
77
166
170 - 349 cc
0
4
41
122
252
350 - 749 cc
0
6
36
119
289
750 cc and Above
0
11
56
173
347
Average street-legal
0
6
36
120
265
Off-Road
99 cc and Below
t)
2
2
22
*
100—169cc
0
1
6
42
*
170 - 349 cc
4
24
91
187
*
353 - 749 cc
7
28
152
222
*
Average off-road
1
8
31
73
*
WORST CASE
Street-Legal
99 cc and Below
100 - 169 cc
170 - 349 cc
350 - 749 cc
750 cc and Above
Average street-i egal
Off-Road
0
0
0
0
0
0
1
1
4
7
13
7
1
50
94
100
138
94
*
96
260
315
362
434
340
*
*
*
*
*
*
24
176
210
224
301
221
27
81
276
321
108
0
7 85 191
7-46
-------
FIGURE 7—5
350
PROJECTED RETAIL PRICE INCREASES VS. REGULATORY
NOISE LEVELS FOR STREET LEGAL MOTORCYCLES
—nominal case—
300
250
200
U )
0
.7
LU
U)
(
U I
C.,
z
LU
C.)
I-
150
100
50
0
87
81 80
SAE J331a REGULATORY NOISE
FIGURE 7-6
79 78
LEVEL—dB
350
75
PROJECTED RETAIL PRICE INCREASES VS. REGULATORY
NOISE LEVELS FOR OFF-ROAD MOTORCYCLES
—nominal case—
200
I 300
U)
0
U j
U)
LU
C.)
2
LU
C.,
2
150
100
350-749cc
170-349cc
50
0
87
100-169cc
99cc and below
86 85 84 83 82 81 80 79 78 77 76 75
SAE J331 8 REGULATORY NOISE LEVEL—dB
7-47
-------
FIGURE 7-7 PROJECTED RETAIL PRICE INCREASES VS. REGULATORY
NOISE LEVELS FOR STREET LEGAL MOTORCYCLES
—worst case—
350
300
‘I ,
L.
o 250
uJ
C l)
<200
U i
C.)
150
Ui
C.)
10o
I-
50
84 82 81 80 79 78
SAE J331a REGULATORY NOISE LEVEL—dB
350
FIGURE 7-8 PROJECTED RETAIL
NOISE LEVELS FOR
—worst case—
PRICE INCREASES VS. REGULATORY
OFF-ROAD MOTORCYCLES
250
200
F 300
In
I-
—
—
0
Ui
z
U.’
C.,
z
150
100
82 81 80 79
SAE J331a REGULATORY NOISE LEVEL—dB
7-48
-------
400
FIGURE 7-9 WT. AVG. PRICE /dO
—nominal case—
350
300
250
U )
5200
- I
0
0
150
100
50
0
86 85 84 83 82 81
80 78 78 77 76 75
dB
FIGURE 7-10 WT. AVG. PRICE /dO
—worst case—
350
300
250
C l )
5200
- I
0
0
150
100
50
096 8584 83 82 8180 79 78 77 76 7
7-49
-------
Table 7—27
PROJECTED MOTORCYCLE PRICE INCREASES
ON A RELATIVE BASIS (1978 DOLLARS)
Baseline RELATIVE PRICE INCREASE (%)
PRODUCT CATEGORY 1978 Price REGULATORY LEVEL (SAE J331a)
(Dollars) 86 dB 83 dB 80 dB 78 dB 75 dB
NOMINAL CASE
Street-Legal
99 cc and Below $581 0 0.2 0.2 3.3 13.2
100 - 169 cc $806 0 0.1 1.2 9.6 20.6
170 - 349 cc $1188 0 0.3 3.5 10.4 21.6
350 - 749 cc $1596 0 0.4 2.2 7.4 18.1
750 cc and Above $2943 0 0.4 1.9 5.6 11.8
Average Street-Legal 0 0.3 2.0 7.6 17.1
Off-Road
99 cc and below $589 0 0.3 0.3 37 *
100 - 169 cc $806 0 0.1 0.7 5.2 *
170 - 349 cc $1321 0.2 1.8 6.9 14.2 *
350 - 749 cc $1540 0.4 1.8 9.9 14.4 *
Average Off-Road 0.1 1.8 2.4 6.8 *
All Motorcycles 0 0.4 2.1 7.4 *
WORST CASE
Street-Legal
99 cc and Below $581 0 0.2 0.2 4.1 16.5
100 - 169 cc $806 0 0.1 6.2 21.8 32.2
170 - 349 cc $1168 0 0.3 8.0 18.0 27.0
350 - 749 cc $1596 0 0.4 6.3 14.0 22.7
750 cc and Above $2948 0 0.4 4.7 10.2 14.7
Averaqe Street Legal 0 0.3 5.7 14.2 22.4
0ff-Road
99 cc and Below $589 0 0.3 0.3 4.6 *
130 - 169 cc $806 0 0.1 4.2 10.0 *
170 - 349 cc $1321 0.2 2.3 13.8 20.9 *
350 - 749 cc $1540 0.4 2.2 14.7 20.8 *
Average 0ff-Road 0.1 0.8 4.8 10.1 *
All Motorcycles 0 0.4 5.5 13.1 *
ormationnó i Tae
7-50
-------
Table 7-28
EXHAUST SYSTEMS
TYPICAL PRICE MARK-UPS
(1978 DOLLARS)
4 into 1 2 into 1
Exhaust System Exhaust System
Cost/Price Dollars (1978) Dollars (1978 )
Muffler Cost 1 $24 $21
Header Cost 1 $48 $24
Total Cost $72
Profit Margin 2 $9 _______
Net to Distributor 2 81
Net Price to Dealer 2 113 70
Suggested Retail Price 2 170 105
Sources:
1. Independent cost estimate
2. Manufacturer supplied data
7-51
-------
Table 7-29
II CREASE Ir J MUFFLER COSTS FOR VARIOUS REGULATORY LEVELS
(1978 DOLLARS)
Baseline Regulatory Level (SAE J331a)
Muffler ____ Cost 83 dB 80 dB 78 dB
4 into 1* $22.5 $30 $39 $52
Percentage Increase +33% +72% +133%
2 into $21 $26 $32 $43
Percentage Increase +24% +52% +106%
* 1otorcycle 750 cc and above assumed
** i otorcycle 250-749 cc assumed
d iden t i mate
Table 7-30
P’ICREASE I J EXi-IAUST SYSTEM PRICES FOR VARIOUS REGULATORY LEVELS
(1973 DOLLARS)
Exhaust Baseline Regulatory Level (SAE J331a)
System _____ Cost 83 dB 80dB — 78 dS
4 into 1 $170 $135 $206 $238
Percentage Increase +9% +21% +40%
2 into 1. $105 $117 $132 $1 8
Percentage Increase +11% +26% +50%
7-52
-------
mates for fractional reduction in fuel economy are listed in Table 7—31 (all
size categories corr ined):
Table 7—31
Regulatory Level [ (A-weighted], SAE J331a)
Present
83dB 80dB 78dB 75dB
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 5 8
Several motorcycle magazines routinely measure fuel economy in the
course of testing motorcycles. Testing sequences are not generally specified
and tend to vary from test to test and magazine to magazine. H iever, a
review of published data for Cycle and Cycle Guide magazine in 1975 indicate
that estimates of 45 m.p.g. for street motorcycles over 170 cc and 70 m.p.g.
for street motorcycles 170 cc and under are reasonably consistent with
reported results. These estimates generally agree with manufactureNSuPplled
information. The data in Section 5 indicate that motorcycles under 170 CC
travel about 2/3 the annual distance of motorcycles over 170 cc. Further the
data in Section 2 indicate that motorcycles under 170 cc make UP approx1-
mately six percent of the Street motorcycle population. These figures can be
combined for a composite fuel economy of current street motorcycle of about 47
m.p.g. Two-stroke engines generally display somewhat lower fuel econofly than
4-stroke models, but large consistent differences were not noted. From these
same reports, 35 m.p.g. for pure off-road motorcycle over 170 cc and 7.0
m.p. . for off-road motorcycles under 170 cc 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. Table
7—32 shows the annual increases in fuel costs for both street and off—road
motorcycles.
Table 7—32
Regulatory Level [ (A—weighted], SAE J331a )
(Qol 1 ar/Year)
86 dB 83 dB 80 dB 78 dB 75 dB
Street: Nominal Case 0 0.48 1.80 3.35
Worst Case 0 0.96 2.87 3.59
0ff-road: Nominal Case 0 0.03 0.26 0.46
Worst Case 0 0.07 0.33 0.53
7-53
-------
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 noise reduc-
tion. There has been no indication that at designing to meet lower noise
level standards result in exhaust systems or other parts are any less durable
than current systems; therefore, no Increase in maintenance is expected. The
nominal and worst case increased labor estimates are listed in Table 7-33
below (all size categories conbined; hours/Years):
Table 7-33
RegulatQ y Level [ (A-weighted), SAE J331a]
86 d B 83dB 80dB 78 d B 75 dB
Street : Nominal Case 0 1/4 1/2 3/4
Worst Case 0 3/8 3/4 3/4
Off-road : Nominal Case 0 1/16 1/4 3/8
Worst Case 0 1/8 3/8 1/2
Although many motorcyclists do their own maintenance, maintenance at a
moderately priced repair facility with a labor rate of $20/hour is assumed
for costing purposes. The resulting increased annual maintenance costs are
listed in Table 7-34 below (1975 dollars/year):
Table 7-34
Regulatory Level [ (A-wei 9 ed), SAE J331a]
86dB 83dB 80dB 78dB 75dB
Street : Nominal Case 0 5 10 15
Worst Case 0 7.5 15 15
Off-road : Nominal Case 0 1 5 5
Worst Case 0 2 7.5 10
7.6 Costs of EPA Air Emission Requirements
The assessed costs and impacts of the noise regulation of motorcycles
will be in addition to those costs and impacts attributable to EPA’s motor-
cycle air emission regulations (40 FR 1122, January 5, 1977). EPA studies
using information supplied by various manufacturers indicate that the cost of
compliance with the air emission standards for 1978 would result in an average
Increase in retail cost of $47 per motorcycle. Also, the manufacturers
estimated that fuel econon y Improvements associated with the 1978 air emission
standards would range as high as 65 percent with an average increase of 20
percent. Consequently, air emission control costs would be partially offset
by an average discounted lifetime fuel savings of $33 and an undetermined
7-54
-------
savings in maintenance and improved rt liability of the product. The average
incremental cost increase for the 1980 air emission standards was estimated to
be $9, which included a small additional improvement in fuel economy. No
significant decrease in sales or shift in market shares (between manufac-
turers) was expected to result from the implementation of the air emission
regulation.
7—55
-------
SECTION 8
ECONOMIC IMPACT N4ALYSIS
-------
SECTION 8
ECONOMIC IMPACT STATEMENT
8.1. New Motorcycle Sales
New motorcycle sales are analyzed first from a historical perspective,
usina actual sales figures from 1967-1978. and second on the basis of a sales
forecasting model. Although the monthly forecasts of demand begin in January
of 1979, the coefficients of the demand equations used for forecasting were
estimated with January 1973 - December 1975 data.*
8 1.1 Historical New Motorcycle Sales and Trends
The trends in the consumer demand for new motorcycles, as shown in
Table 8-1, have closely followed the behavior of the overall economy from
1967-1978. Note that the new registration figures from R. L. Polk and Company
shown in Table 8-1 and Figure 8-2 are not equivalent to total new motorcycle
sales (Figure 8-1), since off—road and competition models are not required to
be registered in most states. The total motorcycle sales data for the 1972-
1978 period was derived from the “Motorcycle Industry Council’s Manufactur-
ing Shipment Reporting System,” which is an account of motorcycle shipment
to dealers for the six (five, after 1975) largest manufacturers.
Definitions used in the Manufacturers Shipment Reporting System are
in Table 8-2. The reporting system was specially designed to provide sales
data for the product categories shown in Table 8-3.
The Motorcycle Industry Council provided EPA with complete monthly
sales data from January, 1972, through December, 1978, for total motorcycle
unit sales. which included retail, wholesale, and regional sales data.
8.1.2 Sales by Product Category
The breakdown of 1978 sales by product category shown in Table 8-4
and Figure 8-3 indicates that street motorcycles accounted for one-half of
sales total. Over two-fifths of the motorcycles (41.7 percent) are street
motorcycles 350 cc and above. The majority of the motorcycles in this cate-
gory have 4-stroke engines. Almost all of the off-road motorcycles from
125 to 349 cc have 2-stroke engines.
Thèi i size categories (i.e., under 100 cc’s. 100-169 cc’s and
170-349 cc’s), for each of which there corresponds a set of demand coeffi-
cients, do not lend themselves to forecasting because these categories
were created specifically for this research only for 1973-1975 by the
Motorcycle Industry Council. Although useful for analysis, these categories
cannot be recreated for 1976, 1977, or 1978. however, the demand for these
motorcycle categories combined can be derived as a residual of the fore-
casted demand for all motorcycles, after subtracting the forecasted denand
for all other size classes.
8-1
-------
Table 8-1
NEW MOTORCYCLE UNIT SALES DATA (1967 _ 1978)(1 )
New Motorcycle New Motorcycles Changes from
Year Registrations (1) old (Est.) •__ PLevious Year —
1978 764,097 998,186 - 7%
(2)
1977 848,588 1,077,280 +
(2)
1976 783,100 1,049,378 +19%
(2)
1975 746,778 880,075 -25%
(2)
1974 1,024,084 1,181,395
(2)
1973 1,189,789 1,501,572 +16%
(2)
1972 1,006,143 1,310,134 +
(3)
1971 928,185 1,238,000 +24%
(3)
1970 751,291 1,002,000 +37%
(3)
1969 549,933 733,000 +26%
(3)
1968 437,498 583,000 +52%
(3)
1967 287,058 383,000 -
Sources: (1) R.L. Polk Registration Data.
(2) Motorcycle Industry Council, “Manufacturer’s
Shipment Reporting System” (data representing most
retail level sales were factored up by the share of
new registrations represented by these sales.)
(3) These sales figures were estimated by assuming
new motorcycle registrations in these years to be
75% of new motorcycles sold (based on 1972, 1973
relationships).
8-2
-------
U)
I .-
U-
0
v - s
0
‘i - s
C
I -
I-
U-
0
C
C
FIGURE 8—2 U.S. NEW MOTORCYCLE REGISTRATIONS, 1967 - 197
1 ,500
1,250
1 ,000
750
500
250
1967
7 ____
SOURCES:
MOTORCYCLE INDUSTRY COUNCIL,
1. 1972—1975 DATA:
“MANUFACTURER’S SHIPMENT —
REPORT ING SYSTEM”
2. 1967—1971 DATA: —
ESTIMATES DERIVED FROM
REGISTRATION DATA
68 69 70 71 72 73 74 75 76 77 78
YEAR
FIGURE 8-1 NE MOTORCYCLE SALES, 1967 - 1978
750
500
/____
SOURC : fiOl
)RCYCL E
250
INC
JSTRY
COL
ICIL
1,250
1,000
1967 1968 1969 1970 1971 1972 1973 1974 1975
YEAR
1976 1977 1978
8-3
-------
Table 8-?
MOTORCYCLE INDUSTRY COUNCIL
MANUFACTURER’S SHIPMENT REPORT
DEFINITIONS
MOTORCYCLE
A vehicle which is fully or partially
propelled by a power source other than
muscular power and designed to travel
with no more than three wheels in
contact with the ground.
INCLUDED IN THIS REPORT ARE :
Two wheel motorcycles
Motorcycles with side cars
Three wheel motorcycles
Mini -cycles
Mini -bikes
All-terrain two and three wheels
Motorized bicycles
Motor scooters
Mopeds
SPECIFICALI.Y EXCLUDED FROM THIS REPORT ARE :
Golf carts
Tractors
Equipment designed specifically
for in-factory industrial uses
Three wheel vehicles with a full
passenger enclosure
SHIPMENTS
Net wholesale shipment of motorcycles
from manufacturers or distributors to
retail dealers. Returns and adjustments
from original shipments should be de-
ducted in the month they occur, not
applied to the original month shipped.
PARTICIPATING MANUFACTURER
The motorcycle manufacturers or whole-
sale distributors who submit regular
shipment reports. The initial partici-
pating manufacturers are American Honda,
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 renuires two 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 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
Street 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.
Dual purpose motorcycle:
A motorcycle which is certified by its mani-
facturer as being in compliance with Federal
Motor Vehicle Safety Standards, designed with
the capability for use on public roads as
ell as off-road recreational use.
-------
Table 8-3
MOTORCYCLE INDUSTRY COUNCIL MANUFACTURERSS
SFIIPMENT REPORTING SYSTEM C/\TEGORIES*
Function Size (Engine Displacement) Engine Type
Street Under 50 cc 2-stroke
Dual Purpose 50 — 99 cc 4-stroke
Off-Road 100 - 169 cc
170 - 349 cc
350 - 449 cc
450 - 749 cc
750 - 899 cc
900 cc and above
*Special categories were devised for purposes of this study, only. The normal
reporting system has different size categories. The street and dual purpose
categories correspond to the street—legal category used in the cost analysis.
Size categories were selected to provide flexibility in the event different
product categorizations were required for regulatory purposes and because it
was desirable to evaluate economic impacts in each category.
Table 8-4
MOTORCYCLE MP RKET SHMRE, BY FUNCTION
1974(% ) 1975(%) 1976(%) 1977(%) l978(% )
Street 40.8 47.4 46.7 52.5 49.5
0ff-Road 20.3 26.6 24.8 26.8 33.4
Dual Purpose 38.9 26.0 28.5 20.7 17.1
8-5
-------
Under 125 cc
(66.7%)
125—349 cc
(27.0%)
350—449 cc
(4.9%)
450—749 cc
(1.4%)
DUAL PURPOSE (17.1%)
FIGURE 8-3 BREAKDOWN OF NEW MOTORCYCLE SALES BY PRODUCT CATEGORY:
450-740 cc
(22 ,0%)
750 cc
STREET LEGAL (66.6%)
1978
OFF-ROAD (33.4%)
Under 125 cc
(11.3%)
Under 125 cc
(35.2%)
350—449 CC 450—749 cc
(8.4%) (3 3%)
8-6
-------
In the actual data base, there were no motorcycles in the following
categories: any motorcycle under 50 cc; dual purpose motorcycles, 750 cc and
above; and off—road motorcycles, Th0 cc and above. In fact, there were very
few off-road or dual purpose motorcycles 450 cc and above.
Total Street, Dual Purpose,__and Off—Road Sales
New motorcycle sales data for total street, dual purpose, and off-
road motorcycles in units and retail level dollars derived from the MIC
Manufacturers Shipment Reporting System are summarized in Table 8-5.
Total motorcycle unit sales, (Table 8-5) including street, off—road and
dual purpose models of all displacement classes, reached a peak of over 1.5
million units sold in 1973, generatinq gross revenues of $1.2 billion dollars,
figures which, even discounting the effects of the 174-1975 recession, have
steadily declined from 1973 to 1978. However, while the unit volume of
annual motorcycle sales in 1978 has declined by one-third since 1973, revenue
in real terms has declined by only 17 percent. This is accounted for by the
25 percent increase in the real average price of motorcycles during this
period.
Of the three functional forms of motorcycles (street, off-road, and
dual purpose), unit sales of dual purpose motorcycles declined the most,
from 550,000 in 1973 to 171,000, in 1978. The real average price of dual
purpose motorcycles actually declined by 2 percent over that period. The
demand for off-road motorcycles, while experiencing price increases roughly
equivalent to the average, has remained fairly steady from 1973-1978; that of
street motorcycles has declined approximately 20 percent while their average
nominal price has almost doubled. Apparently, a shift in tastes has occurred,
away from the wore clumsy, yet versatile, dual purpose motorcycles, toward the
specialized dirt motorcycles for off—road use and also toward street bikes.
Thus the relative market shares of the three functional motorcycles have
changed significantly over this period: street, from 43 percent to 50 percent
off—road from 20 percent to 33 percent and dual purpose, from 37 percent to
17 percent.
spi acement Cl ass
While total street motorcycle unit sales declined from 554,000 units to
494,000 over the period 1972 to 1978 (Table 8-5), there were significant
changes in the market shares of the various displacement classes during this
period (See Table 8-6). The shares of motorcycles in the 125 to 349 cc, 350
to 449 cc, and 450 to 749 cc displacement classes all declined, although the
largest of these, the 450 to 749 cc group, declined the least. The market
share of motorcycles under 125 cc increased dramatically from 1.3 percentin
1974 to 11.3 percent in 1 78; and the share of the sales of motorcycles over
750 cc increased froM 28.4 percent in 1974 to 45.8 percent in 1978. Analagous
to the move away from dual purpose motorcycles to either specifically Street
or off-road motorcycles appears to be a movement away from medium displacement
motorcycles, 125 to 749 cc (which comprise only 42.9 percent of the market),
toward motorcycles that are very large or very small and are suited to more
specific purposes.
8-7
-------
(1) Discrepancies in 1973-1975 data due to derivation technique used on monthly data series.
Source: Motorcycle Industry Council, “Manufacturers Shipment Reporting System” (Data representing retail level sales in
units and dollars factored upward to derive data shown in table).
Table 8-5
NEW MOTORCYCLE SALES DATA FOR TOTAL, STREET, DUAL PURPOSE, AND OFF—ROAD CATEGORIES (1972-1978)
TOTAL _______ 1972 1973 1974 1975 1976 1977 1978
New Motorcycle Sales 1,310 1,501 1,181 830 1,049 1,077 998
(Thousands of Units)
P veraqe Retail Price (1) 756 814 1,095 1,278 1,236 1,321 1,492
(Dollars)
New Motorcycle Sales 991 1,221 1,293 1,125 1,298 1,423 1,489
(Millions of Dollars)
STi E i —____________ ___________ __________
New Motorcycle Sales 554 647 482
(Thousands of Units)
Average Retail Price 1,048 1,087 1,546
(Do] lars)
New Motorcycle Sales 570 703 745
(Millions of Dollars)
1]7 LThU POSE
New Motorcycle Sales 541 550 459
(Thousands of Units)
Average Retail Price 598 639 819
(Doll ars)
New Motorcycle Sales 323 352 376
(Millions of Dollars)
OFF-ROAD
New Motorcycle Sales 225 304 240
(Thousands of Units)
Average Retail Price 434 545 717
(Dollars)
New Motorcycle Sales 98 166 172
(Millions of Dollars
422
1,805
762
490
1,738
852
565
1,794
1,015
494
2,086
1,030
226
299
223
171
834
819
815
907
183
245
182
155
232
260
289
333
758
771
783
913
175
201
226
304
-------
Dual Purpose Motorcycle Sales by Displacement Class
All categories of dual purpose motorcycles (Table 8-5) showed dramatic
declines in unit sales between 1974 and 1978 with corresponding declines in
total dollar sales. The market for dual purpose motorcycles is dominated by
those under 350 cc enqine displacement (i.e., those under 125 cc and those
between 125 and 349 cc). Throughout the period these two classes together
comprised between 84 percent and 89 percent of all dual purpose motorcycles
(See Table 8-7). As a result, with total dual purpose motorcycle sales falling
in 1978 to one-third of their 1973—1974 level (Table 8-5), these two classes
each suffered declines in unit sales proportionately greater than the same
engine displacement classes in any other motorcycle category: street, or
off-road. However, the market shares within the dual purpose motorcycle
cateqory did not shift substantially.
0ff-Road Motorcycle Sales by Engine Displacement Class
Historically, total unit sales of off-road motorcycles have held fairly
steady over the 1974-1978 period (see Table 8-5). Revenues, however, have
almost doubled due to the increases in the average unit price of off-road
motorcycles, from $545 in 1973 to $913 in 1978 (see Table 8-5). Tradi-
tionally, the majority of off—road unit sales have been attributed to the less
than 125 cc and 125 to 349 cc classes (see Table 8-8). Like dual purpose
motorcycles, market shares within the off-road motorcycle category did not
shift substantially over the period.
Dern raph i c Developments
Males of all ages constitute approximately 90 percent of all motorcycle
owners (see Table 8-9), although most owners were males between 20 and 34
years of age. 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 1977, the growth rate for the number of males
with income, for the most part, declined. Thus, the effective demographic
market for motorcycle sales was impaired over this period. Table 8-10
provides the percentage changes in the number of males with income in the age
groups 20 to 24 and 25 to 34 years. The large age group, males 25 to 34
years, suffered declining rates of growth in 1974, 1975 and 1977. The age
group 20 to 24 years decreased sharply in 1975 and 1977. The long—term
growth potential for motorcycle sales may be constrained by the growth rates
in these effective population age groups unless there is a structural shift
in the buying patterns of other age/sex groups.
Real Income Trends
While the real disposable income for the U.S. recovered from its decline
after 1974, ttva real mean income of the effective market for motorcycles
males of ages 20 to 34, continued to decline, although at a slower rate,
through 1975. This age group, traditionally more seriously affected by
8-9
-------
STREET MOTORCYCLE MARKET
Table 8-6
SHARE BY ENGINE DISPLACEMENT CLASS
Less than 125 cc
125 - 349 cc
350 - 449 cc
450 - 749 cc
750 cc. or greater
1974(%)
59.2
33.2
5.2
2.4
1975(%)
55.8
36.0
6.6
1.6
1976(%)
56.2
36.0
5.6
2.2
1974(%)
2L ( )
1976(%)
1977(%)
1978(%)
1.3
2.2
5.9
9.0
11.3
12.8
10.1
8.1
8.6
4.5
31.9
26.1
31.1
21.3
16.4
25.6
24.0
20.1
21.9
22.0
28.4
37.6
34.8
39.2
45.8
Table 8-7
DUAL PURPOSE MOTORCYCLE MARKET SHARE BY ENGINE DISPLACEMENT
CLASS
1974(%)
1975(%)
1! ( )
1977(%)
1978(%)
Less
than
125
cc
31.8
36.2
33.5
35.7
35.1
125 - 349
cc
57.8
50.7
54.0
49.1
53.2
350 - 449
cc
10.1
12.6
10.1
11.2
8.4
450 - 749
cc
.3
.5
2.4
4.0
3.3
Table 8-8
0FF-ROAD MOTORCYCLE MARKET SHARE BY ENGINE DISPLACEMENT CLASS
Less than 125 cc
125 - 349 cc
350 - 449 cc
450 - 749 cc
____ 1978(X )
58.8 66.7
34.0 27.0
4.9 4.9
2.3 1.4
8-10
-------
Table 8-9
MOTUkCYCLE BUYER’S DEMOGRAPHIC PROFILE
Under 16 years
16 - 17 years
18 - 20 years
21 - 24 years
2 - 29 years
30 - 39 years
40 - 49 years
13%
10%
13%
15%
15%
1 ( V
J. /0
10%
A C l
- 10
1%
I JU•
All Owners
4.%
48%
2%
1%
Total 100%
Table 8-10
AGE GROUP PERCENT CHAi’IGE IN THE NUMbER OF MALES WITH
1973 1974 1975 1976
2.46 3.17 .6 3.21
4.60 3.83 3.16 3.81
Males, 20—24
Males, 25—34
Sex
Male
Female
All Owners
91%
( - IC!
/0
Marital
Status ______
Married
Single
Widowed/Divorced
Undes i gnated
AQe
Education
8th grade or less 10%
High school incomplete 24%
High school graduate 33%
College incomplete 20%
College graduate 11%
Median age 24 yrs. Uridesignated 2%
Total Too
Source: allup Organization, “Survey of i ”io orcycle Ownership, Usage,
and Maintenar c&’.
INCOME
1977
1.48
2.49
8-11
-------
downturns in the economy than older age groups, suffered declines in real
mean income of 4.6 and 3.4 percent in 1974 and 1975, respectively (see Table
8-11). The real earning power of the age group 20 to 34 years did not fully
recover in 1976 and 1977, when total real disposable income had been growing
at the rate of 3.7 percent per year. The real income of potential motorcycle
buyers decreased 8 percent during 1974 and 1975, while having increased by
only 2 percent during 1976 and 1977. 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 has not been improving.
Price Trends
The average unit price of motorcycles increased from $814 in 1973 to
$1,492 in 1978, or by 83.3 percent (Table 8-5). During the same period,
the price of all other goods competing for the consumer’s budget, as measured
by the Consumer Price Index, increased by 32.2 percent. Thus the relative
price of motorcycles, compared with all other commodities, increased almost
three times as fast during those five years. Only in 1976 was the situation
somewhat ameliorated, with the real price of motorcycles declining by approxi-
mately 8.5 percent (see Table 8-12 for a comparison of percent changes in the
average unit price of motorcycles and the consumer price index).
With a deteriorating effective purchasing power base for motorcycle
sales and a substantial increase in the real price of motorcycles, the
decline in motorcycle sales over the period 1973 to 1978 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 prices of other products) over the period 1973 to 1975
provided the approach for statistically modeling the determinants of demand
for unit motorcycle sales. The basis of the demand model used in the EPA
analysis was a sales-adjustment equation, which related sales of each period
to sales in the previous period. Statistical equations were estimated eco-
nometrically by relating unit motorcycle sales (by type and function) to sales
in the previous period and to demographic, income, price, and motorcycle
characteristics over the period 1973 to 1975. With these equations the
forecasts of unit sales and revenues (given prices) for each class of motor-
cycle were generated. A more detailed description of this model is in
Appendix F.
The annual forecasts of the demand model, based on the monthly pro-
jections starting in January, 1979, are depicted in Figures 8—4 through 8-8.
By 1990, (Figure 8-4a) total unit motorcycle sales will be only 45.5 percent
qreater than in 1973 (Table 8-1). Furthermore, despite the impressive gains
for motorcycle sales forecast for 1979 and 1980, the 1973 level (Table 8-1) of
1.5 million units will not be reached until 1982. With the assumption that
average unit motorcycle prices will increase by 7 percent per year, total
“iotorcycle revenues will have doubled between 1978 ($1.5 billion) and 1981
8-12
-------
Table 8-11
PERCENT CHANGE IN REAL INCOME OF MOTORCYCLE BUYERS
1974 1975 1976 1977
Disposable Income for the U.S. -1.8 +0.8 +3.7 +3,7
Mean Income, Males, 20 to 34 years -4.6 —3.4 +1.0 +1.0
Table 8-12
PERCENT CHANGES IN THE AVERAGE UNIT PRICE OF MOTORCYCLES AND
THE CONSUMER PRICE INDEX
1974 1975 1976 1978
Average Unit Price of Motorcycles +36.3 +16.1 -2.9 +8.4
Consumer Price Index +11.1 + 9.2 +5.8 +7.6
8-13
-------
2.300
2.200.
2.100
2.000
1.900
1.€ 00
.2
1.700
E
1.600
i. oo
-j
S
— I.
0
I-
1.300
1.200
—
1979 1960 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990
YEAR
FIGURE 8—4a. PROJECTED TOTAL UNIT SALES
-------
iG.oo
15.50
15.00 :
111.50
S
0
1 i.0O
U
C’
13.50
V%
d c
13.00
U i
0
•
95- 12.50
e
o S
12.00
C S
“ 11.50
S
11.00
10.50
10.00 I I I I 1 -
1979 1980 1981 1982 1983 198k 1985 1986 1987 1988 1989 1990
YEAR
FIGURE 8—4b. PROJECTED MEAN INCOME, MALES, AGES 20-34
-------
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
.00
3.00
2.00
1.00
in
cc
— C
— 0
C
C i v ’
> )
C I —
In
—
—
FIGURE 8-5. PROJECTED TOTAL REVENUE VS. TOTAL UNIT SALES
• Total Revenue (billion .$)
A— Total Sales (million units)
1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
YEAR
1990
-------
2.60
C”
C
C
0
— C
—0
— .e
— —
.—
E
UI -
II
— UI
—I, )
1.20
-4
—Jo
i , 1.00
c.I o-
C) ‘4-
1. 0
1J
vi—. 0.80
— “
‘- 0.60
I-
YEAR
FIGURE 8—6. PROJECTED STREET AND OFF-ROAD SALES
•. Total Street Lega1 Sales (million unTts
A Total OffRoad Sales (million units)
2.20
2.00
1 .80
1.60
1.40
0 40
0.20
1979
1980
1931
1982
1983
1985
1987
1988
1989
-------
2.60
2.40
2.20
£
£ £
1.60
1. 0 S
1.20
1.00 S
i.’i 2 0.80
‘a
o
I —
0.40
0.23 •1
1979 1980 1981 1982 1983 1984 1585 1586 1987 i 88 1989
YEAR
FIGURE 8-7. PROJECTED STREET- LEGAL VS. TOTAL UNIT SALES
s—Total Street—Legal Sales m1l1ion units)
£ Total Sales (million units)
-------
2.60
2.40
2.20
C _ £
*
C”
0•-
:C 1.80 £
— C
EO 1.60 £ £
£
• • 1.40
ID
, 4nu £
— 1.20
I
‘ — 1.00
0
—b— 0.80
‘V
4 ’
0.60
S
0.40 0 S
S S
S
0.20 —
1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 19o9 199 O
YEAR
FIGURE 8-8. PROJECTED OFF-ROAD UNIT SALES VS. TOTAL UNIT SALES
s—Total 0ff—Road Sales (million units)
£ Total Sales (million units)
-------
($3.0 billion). By 1990 (Figure 8-5), the total motorcycle market is expected
to reach $8.3 billion. For the purpose of the baseline forecast, EPA has
assumed an annual growth rate in unit motorcycle sales of two percent for the
years 1991 to 2000. After the year 2000, motorcycle sales are assumed to
remain constant.
8.2 Impact on New Motorcycle Demand
The primary impact on the demand for new motorcycles as a result of
the implementation of reciulatory standards is expected to be a reduction
in demand caused by unit price increases that are attributable to riieeting
the specific noise standardS.* The motorcycle demand model described pre-
viously was used to relate demand impacts to the unit price increases shown
in Section 7.
Price elasticities of demand, as derived from the historical data base,
are shown in Table 8-13 below. The elasticities were calculated at the mean
of the independent variable. tt should be noted that the structural form of
the demand equation does not yield constant elasticities. (The slope of the
demand curve is the invariant in the demand model; i.e., the ratio of the
change in demand to a chanqe in price.) For the forecast period 1979-1990,
the composite price elasticity of demand for all motorcycles was approximately
—1.1, with price elasticities for street and off-road motorcycles of approxi-
mately -1.2 and -.75, respectively.
Table 8-13
MOTORCYCLE PRICE ELASTICIfY
Displacement i 6 t6 le Category
Class ____ Street Dual Purpose 0ff—Road
Below 100 cc -.928 - .867 - .953
100-169 cc -.935 -.997
170-349 cc -.967 -.74 -1.148
350-749 cc -.836 -.912
750 cc dnd above -. 768 - .45
*potentjal shifts in demand, not calculated as part of the economic impact
analysis, might be caused by changes in styling, safety and performance which
are required to meet a mandated noise level.
8-20
-------
Table 8-14
MOTORCYCLE NOISE EMISSION STUDY LEVELS AND EFFECTIVE DATES
Regulatory Level
Date ( SAE J331a )
January, 1981 83 d13
January, 1983 80 dB
January, 1986 78 dB
January, 1990 75 dB
Four regulatory levels effective on the dates shown in Table 8-14 were
studied. The noise standards used in this analysis are expressed in not-to—
exceed levels. Based on available data for each regulatory level, manufac-
turers must design their products to meet a level 2 to 3 dB less than the
noise standard to allow for production and testing variabilities. Throughout
the analysis, this level will be called “design level”.
Estimates of reductions in demand are summarized in Table 8-15, 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 negative price
elasticities for motorcycles that may result from increases in retail prices
which can be attributed to noise control. The projected reductions for each
study level that was analyzed are shown in Figure 8-10. The data indicate
that signficant reductions in demand are expected for noise emission standards
lower than 80 dB (SAE J331a).
The impact of each standard is discussed in detail below.
83 dB Regulatory Level, 1981
The baseline demand forecast for all new motorcycles in 1981 is 1,467,000
units, broken down as follows: 1,165,000 street motorcycles, and 302,000 off-
road motorcycles. An 83 dB regulatory level in 1981 (SAE J33la) is expected
to reduce demand by 0.4 percent in both the nominal case and the worst case.
80 dB Regulatory Level, 1983
This standard is expected to reduce demand by 2.1 percent in the nominal
case and by 5.1 percent in the worst case. The product category with the
largest potential impact is street motorcycles under 350-449 cc. Reduction in
demand is expected to be at least 2.5 percent in the nominal case and 6.8
percent in the worst case for this product category.
8-21
-------
Table 8-15
ESTIMATED RELATIVE REDUCTION IN DEMAND FOR NEW MOTORCYCLES
DUE TO NOISE CONTROL REGULATIONS
FIRST YEAR FOR EACH STANDARD
RELATIVE REDUCTION_IN DEMAND (% )
CATEGORY YEAR 1981 1983 1986 1990
ulatory Level* 83 dB 8( dB 78 dB 75d8**
Nominal (Expected) Case -_____ ___________
Street_Legal*** 0.3 2.0 5.4 14.4
350-449 cc 0.4 2.5 6.7 14.7
450-749 cc 0.3 1.5 4.4 9.6
750 cc and above 0.2 0.9 2.5 4.6
0ff-Road 0.7 2.7 5.2
All Motorcycles 0.4 2.1 5.4
Worsfase
Street Legal** 0.4 5.1 10.0 18.6
350-449 cc 0.5 6.8 12.8 18.6
450-749 cc O..3 4.4 8.3 12.1
750 cc and above 0.2 2.3 4.4 5.8
Off-Road 0.8 7,7
All Motorcycles 0.4 5.1 9.5
*Not to exceed regulatory level (SAE J331a).
**Cost figures for 75 dB available only for street motorcycles.
***Categories under 350 cc are excluded here since these categories cannot be
forecasted; i.e., the categories of engine size routinely collected by the
Motorcycle Industry Council do not match the categories for which the
demand equations were estimated.
8-22
-------
V
4 ’ ,
Ci’- .
U 4
.—
uc
0
00
‘a—
42
42E
L
‘a
4’,
12
=
2.000
I . 900
1.800
1.700
1.600
1.500
1.400
1.300
1.200
1.100
1.000
0.900
1979 1980 1981 1982 1983 1984 1985 1986
YEAR
FIGURE 8-10. ESTIMATED REDUCTION IN DEMAPID FOR NEW STREET-LEGAL MOTORCYCLES
DUE TO NOISE REGULATIONS
• — Base Case
— Nom na1 Case
R- Jorse Case
1987 1988 1989
1990
thaded area Indicates nominal and worst case bounds)
-------
78 dB Regulatory Level, 1986
A 78 dB standard in 1986 could reduce the baseline forecasted demand by
5.4 percent in the nominal case and by 9.5 percent in the worst case. The
product categories projected to be affected the most would again be street
motorcycles under 350—449 cc. Motorcycles in these categories experi-
ence the greatest relative price increase, because they are the most sensitive
to price changes; i.e., they have larger price elasticities. The street
motorcycles, 750 cc and above, are expected to have the least severe impact:
2.5 percent reduction in the nominal case and 4.4 percent in the worst case.
This motorcycle category is the least sensitive to price increases.
8.3 Impacts on Dern or Products and Services
8.3.1 historical Afterrnarket Sales and Forecasts
The motorcycle afterriiarket industry represents sales of motorcycle
replacement parts, accessories, apparel, and services. A broader definition
of the aftermarket would include motorcycle insurance and miscellaneous items
such as consumer publications, and advertising. The motorcycle aftermarket
industry has experienced extremely rapid growth. Afterinarket sales in 1975
were estimated* at $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 doubled between 1972 and 1975.**
Table 8-16 provides estimated after”iarket sales for the period 1972 to 1975.
The aftermarket industry is being stimulated by the growing base of
motorcycle owners, improved advertising and merchandising, new products, more
affluent riders, and the trend toward using motorcycles for basic transpor-
tation. With the growth of the motorcycle population, one of the most useful
ways to consider aftermarket sales is expenditures per motorcycle in use.
Expenditures per motorcycle in use as displayed in Table 8—16, have been
growing at the rate of approximately 20% per year.
A Ziff-Davis motorcycle aftermarket survey taken early in 1975 indi-
cated that approximately 85 percent of all notorcycle/rninicycle owners pur-
chased replacement parts, accessories, and apparel items from the motorcycle
aftermarket industry.*** Twenty-two percent of these consumers spent more
than $100 for their purchases. On the average, each owner spent $86 for such
items as: replacement parts and accessories ($54), and clothing ($32).****
A detailed breakdown of 1974 motorcycle aftermarket sales, as derived
from the Ziff—Davis Study, is shown in Table 1_17. Each of the major compo-
nents of afterniarket sales, replacement parts and accessories, apparel,
service and repairs, insurance, and miscellaneous, is described in more
detail in the following paragraphs.
€f T€- arketsa1es and growth trends are approximations because
the an organized motorcycle aftermdrket industry is relatively new and no
oraaniz d data collection effort by the industry has been made. Most of
the detailed data available are for calendar year 1974.
** Frost and Sullivan, “Motorcycle Original Equipment and Aftermarket
Study Announcement,” April, 1975.
*** Ziff—Davis Publications, “Motorcycle Aftermarket Study,” 1975.
**** Ibid.
-------
Table 8-16
AFTERMARKET SALES GROWTH*
Total Number öT A ermarket Sales
Sales Percentage Motorcycles in Use per Motorcycle
Year ( Millions of $) Increase ( Millions of Units ) _____In Use —
1972 $ 764 5.4 $ 141
1973 $ 1,070 (1) 40% 6.2 $ 173
1974 $ 1,500 40% 7.1 $ 211
1975 $ 1,810 (2) 20% (2) 7.2 (3) 251 (3)
Sources: 1. The 1974 data point obtained from Ziff—Davis Publishing Company,
“Motorcycle Aftermarket Study”.
2. Estimates provided by Motorcycle Dealer News.
3. Estimates derived from EPA’s forecast model of the
motorcycle stock.
* Data for aftermarket sales and growth trends are approximations because
the an organized motorcycle aftermarket industry is relatively new and no
organized data collection effort by the industry has been made. Most of
the detailed data available are for calendar year 1974.
8-25
-------
Table 8-17
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 12.1
Cafe Racing Kits 4.1
Carburetors 8.7
Chain Lubricants 79
Cleaners and Waxes 3.8
Custom Seat 12.9
Drive Chain 18.1
Exhaust System Products 30.6
Fairinqs 29.2
Fenders 6.6
Gas Tank 9.0
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 1.4
Spark Plugs 24.6
Specialty Wheels 13.4
Sprockets 16.7
Tools 31.4
Windshields 5.2
Apparel 223
Service Receipts/Repair 450
Insurance * 385
Miscellaneous (Consumer Publications, etc.) 50
Total 1,508
Source: Ziff-Davis Publications Motorc l (f€ ”
* Energy and Environmental Analysis, Inc., “Economic Assessment of Motorcycle
Exhaust Emission Regulations”.
8-26
-------
Apparel
Sales of apparel (including helmets) were estimated to be over $200
million in 1974. The same manufacturers, distributors, and retail outlets
that are affected by changes in the market for replacement parts and access
ones will be affected by changes in the market for apparel.
Sen v / p irs
Service and repair receipts totaled an estimated $450 million in 1974.
Service revenues are increasing principally because of the larger population
of motorcycles in use. Service receipts primarily affect dealers, since on
the average these receipts comprise 15 percent of each dealer’s revenue.
Insurance
Motorcycle owners paid an estimated $385 million for insurance premiums
in 1974. Average premiums generally vary with motorcycle size. Changes in
the demand for motorcycle insurance will have very little effect on the
motorized vehicle insurance industry, since motorcycles are 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.
Replacement Parts and Accessories
The market for parts and accessories in 1974 was estimated at $400
million, which represented approximately 27 percent of afterrnarket sales.
Aftermarket items are generally purchased for performance, styling, func-
tional or maintenance purposes. Exhaust system products, mechanical products,
mechanical parts and hop-up kits are big sellers in this category. Sales of
stylinq/functional items such as fairings, windshields, saddle bags and
tote-boxes that appeal to riders of large street touring motorcycles are
increasing significantly as a result of the increased growth of these types of
motorcycles. Any change in the demand for replacement parts and accessories
will directly affect afterniarket manufacturers, distributors and retail
outlets such as dealers, accessory shops,discount stores and mail order
firms.
Exhaust System Sales
Sales for exhaust system products, which were $30.6 million in 1974,
will be particularly impacted by the motorcycle noise control standards.
Results of a survey from Ziff-Davis publications for exhaust system purchases
8-27
-------
by motorcycle owners in 1974 are shown in Table 8-18. These data indicate
that 616,000 buyers (8.7 percent of all motorcycle owners) purchased 1.4
exhaust system products (mufflers, expansion chambers, etc.) each, and spent
an average of $50 for each purchases or $35 per unit. Most of the exhaust
system products (63.5 percent) were purchased from dealers. For forecasting
purposes, the most feasible way to Consider exhaust system sales is to relate
those sales to the number of motor’CYcle in use (the stock of motorcycles).
For 1974, and average .1214 exhaUst systems were sold per motorcycle in use.
Using this relationship and forecasts of the population of motorcycles, as
derived using Motorcycle IndustrY Council scrappage rates* and new motorcycle
sales projections, forecasts of exhaust system sales (in units) were devel-
oped. These forecasts are shown in Table 8-19.
8.4 Total Annualized Costs
Increases in purchase prices and operation and maintenance costs for
each of the regulatory study levels (Table 8-21) will costs attributable to
noise control. Purchase price increases are incurred at the time of sale, and
operation and maintenance costs are incurred annually for the life of the
product.
To compare regulatory options (See Table 8-21) for a given product and
between products, it is necessary to use a statistical metric to characterize
this cost stream. The statistical metric used for all new product noise
regulations is “uniform annualized costs”, or more simply, annualized 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 present “alue
using a specified time value of money. This present value is 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 con-
verted to an annuity over that same period. This statistical metric accounts
both for the size and timing of costs incurred. The individual purchase price
in creases developed in the previous sections were used to calculate total
purchase price increases in each year based on specific not-to-exceed study
levels and effective dates. The number of units sold in each year was ad-
justed by the expected decrease in demand calculated in Section 8.2. In-
creased purchase prices were converted to 1978 dollars. Similarly, the
increased operation and maintenance costs that were developed were applied to
the stock of vehicles in any year (adjusted for decreased demand), and ex-
pressed in 1978 dollars.
8.4.1 Vehicle Annualized Costs
Table 8-21 shows the regulatory study levels used in computing annualized
costs. Four street and four off-road regulatory options were assessed.
*The Motorcycle Industry Council’s estimates of “survival” rates for motor-
cycles over time is reproduced in Table 8-20. The scrappage rate is equal to
one minus the survival rate.
8-28
-------
Table 8-18
EXHAUST SYSTEM SALES
Exhaust
System
Products
Purchased New Products in Past 12 Months (Percentage of Total o.
of Motorcycle Owners) 8.7%
total Number of Buyers 616,000
*
Average Number of Exhaust System Products 1.4
Total Exhaust System Products Purchased 862,000
Average Amount Spent per Purchase $49.73
Total Dollar Volume $30,633,000
Where Purchased**
Dealer where motorcycle was purchased 22.2%
Other motorcycle dealer 41.3
Motorcycle accessory shop 25.0
Chain/department store
Discount auto center 1.0
Mail order 7.7
Other LU
Not stated 4.8
Source: Ziff-Davis Publications, “Motorcycle Aftermarket Survey”, 1975.
* “Products” include any portion of a complete exhaust system; i.e. headers,
mufflers, expansion chambers, etc.
** May add to more than 100% due to multiple answers.
8-29
-------
Table 8-19
FORECAST OF MOTORCYCLE EXHAUST SYSTEM PRODUCT SALES
Year Motorcycle Stock Exhaust System Unit Sales
1979 6705773 814080
1980 6919239 839995
1981 7339283 890988
1982 7847119 952640
1983 8381039 1017458
1984 9015023 1094423
1985 9728584 1181050
1986 10428851 1266062
1987 11081532 1345298
1988 11692021 1419411
1989 12227645 1484436
1990 12695499 1541233
1991 13105633 1591023
1992 13473094 1635633
1993 13811213 1676681
1994 14128853 1715242
1995 14434729 1752376
1996 14735735 1788918
1997 15036404 1825419
1998 15339588 1862226
1999 15647346 1899587
2000 15960715 1937630
2001 16224706 1969679
2002 16439736 1995783
2003 16605914 2015957
2004 16725635 2030492
2005 16806268 2040280
2006 16858094 2046572
2007 16890492 2050505
2008 16909154 2052771
2009 16918788 2053940
2010 16923084 2054462
8-30
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Table 8-20
MOTORCYCLE SURVIVAL RATE 1
Probability
of a
Motorcycle
Being in
Operation
0.3
0.2
Survival
Age(yrs) Rate
— 0.5 .o
• .5 0.93
2.5 0.96
3.5 %)90
4.5 0.75
5.5 0.55
6.5 0.37
7.5 0.26
8.5 0.17
9.5 0.10
10.5 0.05
0.02
12.5 0.01
Source: 1. Yamaha’s Cormient on Emission Control Plan for New Motorcycles,
Submitted to California Air Resources Board by Yamaha Motor Co.,
Ltd. , Japan, Apri 19Th.
(.J
10
0.9
0.8
07
Os
0.5
0.4
0
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Table 8-21
REGULATORY STUDY LEVELS
Effective Date
Regulatory
Option 1981 1983 1986 1990
I -Si 83 dB
11 -S 83 80
111-S 83 80 78
IV-S 83 80 78 75
*Street Motorcycle
Regul atory
Option 1981 1984 1987 1991
I_OR** 86 dB
Il-OR 86 82
Ill-OR 86 82 80
IV-OR 86 82 80 78
** Off-Road Motorcycles
Table 8-22 displays the nominal and worst case estimates for increases
in annualized costs that correspond to purchase price increases expected at
the various study levels. Also included are annalyized operation and r ain—
tenance cost incrases. The worst case estimates range up to $343 per motor-
cycle (1978 dollars) for street motorcycles at 78 dB. The cost stream for
each of these regulatory options was assessed over a 30 year period (through
2010) to ful1y account for the costs of the ultimate level.
Ten percent was used for the time value of money. For each regulatory
option, nominal and worst case estimates were calculated.
Operation and maintenance costs were applied to the existing motorcycle
stock for each year. The motorcycles were assumed to have an average life of
6.1 years, after which they were retired.
8.4.2 Aftermarket Exhaust Annualized Costs
1 Aftermarket exhaust system prices as a result of noise regulation
will increase due to two factors: (1) inexpensive non-complying systems
8-32
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Table 8-22
TOTAL ANNUALIZED COSTS
(MILLIONS OF DOLLARS)*
Street Motorcycles
Regulatory Level ( dB J331a )
Nominal ( Expected) Case 83 80 78 75
Annualized Purchase Costs 10 56 150 237
Annualized (JIM Costs 0 35 63 88
Total Annualized Costs 213 325
Worst Case
Annualized Purchase Costs 11 109 241 299
Annualized 0/M Costs 0 67 102 110
Total Annualized Costs 11 176 343 409
0ff-Road Motorcycles with Engine Di R1acement Less than 170cc
Regulatory Level (dB J331a )
Nominal ( Expected) Case 86 82 80 7h
Annualized Purchase Costs 0 .6 1.1 6.0
Annualized O/M Costs 0 0 1.3 5.6
Total Annualized Costs — .6 2T4 11.6
Worst Case
Annualized Purchase Costs 0 .6 4.3 10.3
Annualized (JIM Costs 0 .0 2.6 8.2
Total Annualized Costs T6
0ff-Road Motor ç cles_with Engine Displacement Greater than 170 cc
Req latory Level (dBJ33la )
Nominal_(Exyected)_Case 82
Annualized Purchase Costs 0.9 3.1 10.7 . 1.4.9
Annualized O/M Costs 0 .6 2.6 3.4
Total Annualized Costs 3.7 f3.3 T8.3
Worst Case
Annualized Purchase Costs 0.9 3.8 17.1 21.4
Annualized 0/N Costs 0 1.3 3. 4,
Total Annualized Costs 0.9 51 20.9
wT T56lTa r
3-33
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will be eliminated, and (2) currently complying systems becoming more expen-
sive since compliance to lower noise emission levels may require greater
complexity. Total annualized costs will be calculated for this second fac-
tor only. It is reasonable to assume that the fractional increase in prices
of currently complying aftermarket Systems will parallel the fractional
increase of OEM systems at the same level. Based on Table 7-27, the following
increases for currently complying (i.e., those on the range of OEM noise
levels) aftermarket exhaust systems are assumed:
Regulatory Level (SAE J331a)
83 dB 80 dB 78 dB 75 dB
Fractional Increase in Price 10% 25% 50% 100%
To establish the current price of complying after,narket systems, prices
for current complying systems were compared to OEM replacement prices. While
some systems for the popular models are less expensive than OEM replacements.,
others are up to $45 more expensive. This comparison is complicated by
different exhaust system configurations and the presence or absence of header
pipes. The OEM replacement price for large motorcycles exhaust systems varied
between $100 and $250, with many such exhaust systems costing approximately
$175. With replacement systems for smaller motorcycles factored in, $125 was
used as the average current price of complying aftermarket systems.
Another factor necessary to compute annualized costs was the impact
of regulation on demand for afterniarket exhaust systems.* Using price elas.-
ticity alone would be unrealistic because it does not account for performance
and styling impacts. In addition, such factors would be applicable only
for price increases in a narrow range, which was not expected for aftermarket
systems. Based on discussions with afterrnarket manufacturers, the following
reductions in demand were estimated:
Regulatory Level (SAE J331a)
83 dB 80 dB 78 dB 75 dB
Reduction in Demand 30% 40% 50% 60%
* ReëalT that the demand for aftermarket exhaust systems (f or a specific
noise standard) is a function of the stock of motorcycles complying with
that standard. The stock of motorcycles is itself influenced, through price
effects, by the motorcycle noise standards. The impact of an aftermarket
exhaust system noise standard, hc ever, is restricted to the price and
demand impact on aftermarket sales for the (aftermarket baseline) motorcycle
stock consistent with that specific noise standard.
8-34
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The increase in purchase price and reduction in demand were combined to
calculate total annualized costs:
Regulatory Level (SAE J331a)
83 dB 80 dB 78 dB 75 dB
Afterniarket Exhaust
Systems Total Annualized
Costs ($M) 1.7 3.4 5.1 6.9
8.5 Impact on U.S. Employment Vehicle Manufacturers
Harley-Davidson and Kawasaki are the major motorcycle manufacturers with
assembly facilities in the U.S. Assuming that these manufacturers will remain
in the market at any regulatory level, their decrease in employment should
follow the total market’s cf crease in demand. Based on elasticities developed
from historical price-sales relationships, the following impacts on employment
would be expected at each regulatory level: 83 dB--30 positions; 80 dB--160
positions; 78 dB-- 450 positions; 75 dB-—1200 positions. However, if the
noise standards prevent AMF/Harley Dividson from remaining in the market, its
3,300 motorcycle-related jobs in Milwaukee, Wisconsin and York, Pennsylvania
would be affected.
Aftermarket_Manufacturers
Total employment in the exhaust system manufacturing industry is expected
to follow the jni act on total demand for such systems. Some firms are ex-
pected to increase production, but a large number are expected to be forced
out of the replacement exhaust system industry at any regulatory level. L’sing
the same assumptions as in Section 8.4.2, the decrease in exhaust system
manufacturing employment would be: 83 dB——375 positions; 80 dB--500 posi-
tions; 78 dB--665 positions; 75 dB--750 positions. Other aftermarket manufac-
turers (of apparel, insurance, etc.) are expected to suffer employment losses
proportional to the change in the population of motorcycles. That population
effect will increase over time until all existing motorcycles comply with the
regulation. On average, the employment effect will be: 83 dB--20 positions;
90 dB—-100 positions; 78 dB--250 positions; 75 dB--650 positions.
Distributors/Dealers
Employment among 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 e’ ’loyment is expected to be: 83
dB——200 positions; 80 dB-—l000 positions; 78— • ) positions; and 75 dB--7000
positions.
Total U.S. Erijpjoyment rmpact
Table 8-23 shows the total expected employment impact at each reciulatory
8-35
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level. Although the levels assessed are for Street motorcycles, comple-
mentary off-road regulations are also expected to contribute to the totals
shown.
Table 8-23
EXPECTED U.S. EMPLOYMENT IMPACTS
Regulatory Level (SAE J-331a)
83 dB 80d5 78 dB 75 dB
Vehicle Manufacturers 30 160 450 1200
Aftermarket Exhaust System 375 500 625 750
Manufacturers
Other Aftermarket 20 100 250 650
Manufacturers
Dealers/Distributors 200 1000 2700 7000
Total 625 1760 4025 9600
8.6 Regional Impacts
The largest employment impacts are expected to occur at the dealer!
distributor level. Except for a certain amount of concentration in Cali-
fornia and other regions of high motorcycle interest, this impact is expected
to be distributed evenly nationwide. The largest regional impact is expccted
to be in Southern California, where most of the aftermarket exhaust system
manufacturers. Other regional impacts could occur in Milwaukee, Wisconsin,
York, Pennsylvania, or Lincoln, Nebraska if Harley-Davidson withdrew from the
market or if Kawasaki closed its U.S. assembly plant. In each of these re-
gions, however, motorcycle related employment is a very small fraction of
total area employment.
8.7 Impact on GNP and Inflation
Total annualized costs for the 78 dB regulatory level are less than $230
million annually. Since this figure constitutes considerably less than
one-tenth of one percent of the U.S. economy, there is expected to be no
sufficient impact on the U.S. Gr,oss National Product nor on general inflation
as a result of this regulation. Since motorcycles are primarily consumer
oriented goods, price increases are not passed along in higher prices for
other commodities, and no inflation multiplier applies.
8-36
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8.8 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 motorcycles from Japan.
At an average purchase price of about $1000 per motorcycle (1973 dollars)
this represented about $1.3 billion in imports, almost 14 percent of the total
$9.6 billion in goods imported from Japan in that year.
Clearly, any large impact on Japanese motorcycle revenues could affect
this balance significantly. However, the price elasticities of demand
associated with the forecasts of sales impacts as a result of the motorcycle
noise regulations are approximately unity; hence the impact on Japanese
motorcycle revenues is expected to be negligible. On this basis, the balance
of trade with Japan is forecasted to be relatively unaffected by any motor-
cycle noise regulations.
8.9 Expected Impacts on Individual Manufacturers
8.9.1 Street Motorcycles
Honda Honda currently produces several motorcycle models that would meet
an 80 dB (F-76a) regulatory level (GL-1000, CB-750F, CB-500T, CB-360T,
XL—250). Honda is expected to have little difficulty bringing its entire
model line into compliance with this level with no major model changes.
Further reductions to the 78 dB 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. EPA
expects that qiven 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 75 dB level. Based on current levels of the larger
models, the CB-750F and CB—500T (no longer in production) appear to be can-
didates for achieving this regulatory level.
Yamaha Based on the current levels of Yamaha motorcycles, EPA
expects that most models will comply to the 80 dB (F-76a) regulatory level
without major model changes. The XS-750 indicates Yamaha’s ability to produce
large 4—stroke models with low mechanical noise. At the 78 dB regulatory
level, several models may require major model changes including liquid cool-
ing, depending on the mechanical noise contribution to the total vehicle
noise. Even with extensive use of liquid cooling, Yamaha might have great
difficulty in producing a large number of models at the 75 dB level,
Kawasaki Based on the current levels of Kawasaki motorcycles, most
models wouTdcomply to the 80 dB (F-76a) level without major model changes.
The most difficult model to quiet would be the KZ-900 motorcycle, its F-76a
level is louder than average for a similar size motorcycle tested by the
J-33la procedure. At the 78 dB regulatory level major model changes, includ-
ing liquid cooling, may be necessary for the larger street motorcycles.
8-37
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Even with extensive use of liquid cooling, Kawasaki might have great difficul-
ty in producing a large number of models at the 75 dB level.
Suzuki Based on current levels of Suzuki motorcycles, most models would
compl T to the 80 dB (F-76a) regulatorY level without major model changes.
Suzuki motorcycle generally tested quieter than average for the F-76a test and
the larger motorcycles are already near the 80 dB level (t. T-75O, GT-550,
RE-5). Suzuki’s recently introduced 4-stroke models incorporate many quieting
features. At the 78 dB level, several models may need major model changes.
The GT-750 and RE—S 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 75 dB level.
AMF/Harley-Davi dson
(1) Large Models
Harley-Davidson motorcycles equipped with “California exhaust systems”
meet the California 83 dB (SAE J331a) standard. It is apparent that current
Harley-Davidson engines types would need major redesign to meet an 80 dB
Federal standard. All known quieting techniques, perhaps including liquid
cooling, may be necessary at this level. EPA believes that there i- a reason-
able chance that Harley-Davidson models may be able to achie’ an 80 dB
regulatory level without major redesign. Extended lead time may be an
important factor in Harley-Davidson’s ability to meet the 80 dB regulatory
level.
It is clear, however, that levels below 80 dB are probably not achievable
with the current engine types. Completely new engine designs will probably be
necessary. Again, lead time for such effort would be a significant consid-
eration.
It is clear from other manufacturers of large-bore twins, however,
that the 75 dB level is essentiallly unachievable with these designs (see
BMW, Moto Guzzi, Ducati). Considering Harley-Davidson’s marketing position,
it maybe impractical for then, to switch engine types to the rnulti-cyclinder
designs common to the Japanese manufacturers.
(2) Small Flodels
Based on current noise levels, the Harley-Davison 2-stroke models should
be able to meet an 80 dB requirment without major model changes. Major model
changes may be necessary at the 78 dB level and the 75 dB level may not be
achievable.
BMW BMW motorcycles tested much quieter than average for the F-75a
test and 80 dB is expected to be achievable with little change to current
models. BMW felt that levels below 80 db SAE J331a; 77—78 dB for F-76a for
these motorcycles were unachievable with their large bore, and horizontally
opposed twin cylinder engine.
Moto Guzzi, Ducati,Benelli,_MVA 9 usta ,_MotoMorini These Italian
manufacturers of large street motorcycles felt that 80 dB (SAE J331a; also
8-38
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estimated to be 80 dB on F-76a) was possibly achievable but at levels below
80 dB, the small fraction of their motorcycles produced for the U.S. would
force them to consider withdrawing from the U.S. market.
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 requlations applicalble to street motorcycles. The combined effect of
these regulations could cause Can-Am to drop these models from the U.S.
market if required to meet an 80 dB or lower 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
83 dB standard. Since demand for 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 regula-
tions could cause Bultaco to drop enduro models from the U.S. market at or
below the 80 dB level.
Other Manufacturers Montesa, KTM, 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 stan-
dards, they will be sold as strictly off-road motorcycles in the future.
8.9.2 0ff-Road Motorcycles
Honda, Yamaha, Kawasaki, Suzuki All of the major Japanese manufacturers
could use technology developed for their street and dual purpose motorcycles
to meet an 86 dB level. Given sufficient lead time, all manufacturers
are judged capable of 4-stroke conversion and mechanical treatment to achieve
an 80 dB regulatory level for large off-road motorcycles and a 78 dB regula-
tory level for small off-road motorcycles. At these levels, however, perfor-
mance impacts can be expected.
Other Manufacturers Husqvarna, Can-Ani, Bultaco, OSSA, Montesa, KIM,
Maico, CZ, Carabela, and several other manufacturers produce off-road and
competition MX motorcycles. Almost all of the manufacturers consulted by
EPA agreed that the 86 dB Calfornia standard was achievable at only a limited
performance penalty. The manufacturers generally felt that 83 dB might be
achievable at some time in the future, but that consumer shifts to higher
performance competition models and user modifications to restore lost perfor-
mance would make this effort fruitless. Since these manufacturers specialize
in high performance, below the 86 dB level demand for their products would
drop off significantly in comparison to the demand for lower priced Japanese
models. Between 83 and 80 dB, most of these manufacturers would either
drop out of the U.S. market or would market competition models only.
8-39
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8.9.3 Aftermarket Exhaust Systems
Approximately half of the firms currently making replacement motorcycle
exhaust systems will probably 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 systems, 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 pro-
ducts may be forced to find new suppliers, or to discontinue selling exhaust
systems entirely. Some firms may resort to copying the designs of other
manufacturers, a common practice at present.
The ten to twenty leading firms in the industry are expected to be
able to produce complying systems, but at similar price and performance
characteristics as 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 aftermarket 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 and local level to prohibit wide-
spread sale and use of loud systems “designed” for motorcycles manufactured
before the effective date of the Federal regulations or “competition” exhaust
systems that can be easily modified by the operator for use on a regulated
motorcycle.
8-40
J.S. GOVERNMENT PRINTING OFFICE:1981 341-082/216 1-3
-------
TECHNICAL REPORT DATA
(Mease read /‘uLrucliwzs on nw ieiersc bcjorc coin, ktwg
1.R R 6798021
3. RECIPIENTS
SUBTITLE
Analysis for the Noise Emission Regulations
for Motorcycles and Motorcycle Exhaust Systems
5 POR
Juecembg 99R0
6.PRPORM!NGORGANIZATIONCOOE
EPA! 200/02
7. AUTHOR S)
8. PERFORMING ORGANIZATION REPORT NO.
EPA 55O/9— 30-217
9. PERFORMING ORGANIZATION NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Noise Abatement and Control (ANR-490)
Washington, DC 20460
10. PROGRAM ELEMENT NO.
.
11.CONTRACT/GRANTNO.
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Noise Abatement and Control (ANR-490)
Washington, DC 20460
13. TYPE
Fina OA
14.SPONSORINGAGENCYCOOE
EPA/200/02
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This document presents the technical data and analyses used by EPA in developing
the noise emission regulations for motorcycles and motorcycle exhaust systems. The
information presented includes a detail.ed discussion of: the motorcycle and
motorcycle exhaust systems industry; baseline noise levels for current motorcycles;
the noise control technology available the adverse health and welfare impacts of
motorcycle noise and the potential benefits of regulation; the expected costs and
potential economic effects of regulation; and the noise measurement methodology.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
C. COSATI Ficid/Group
Street Motorcycles, mopeds, off-road
motorcycles, motorcycle exhaust s ystems,
noise emission requlation, environment
benefits, health arid welfare benefits,
economic effects.
13. DIST?.tSUT ON StATEMENT
Release unlimited
19. SECURITY CLASS (.‘hi Repon)
Unclassified —
20. SECURITY CLASS Thisp ge)
21. NO. OI PAGES
333
22. PRICE
EPA Form 2220.1 (9.73)
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