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Regulatory

Announcement

 Printed on Recycled Paper

United States

Environmental Protection

Agency

Air and Radiation EPA420-F-03-044

December 2003

Office of Transportation and Air Quality

EPA Finalizes Emission Standards for

New Highway Motorcycles

The U.S. Environmental Protection Agency (EPA) is adopting more

stringent emission standards for new highway motorcycles. Under the

current standards, which are over 20 years old, today’s motorcycles

produce more harmful emissions per mile than a car or even a large

sport utility vehicle (SUV). These new standards will reduce the

combined hydrocarbon and nitrogen oxide emissions in the exhaust by

50 percent as well as the harmful health effects of mobile source air

toxics.

Final Rule Highlights

EPA has been working to reduce emissions from motor vehicles for over

thirty years, including emissions standards for highway motorcycles that

we adopted in 1978. In this final rule, EPA is adopting new emission

standards for exhaust and evaporative emissions from highway motorcycles. The standards are based on comparable requirements adopted in

California. The final rule extends the California requirements nationwide

two years after they initially take effect in California. In addition to

updating exhaust emission standards for currently regulated motorcycles,

the new emission standards will include previously unregulated motorcycles with engines of less than 50 cubic centimeters displacement

(scooters and mopeds). We are also adopting new evaporative emission

standards to control the loss of gasoline (described as "permeation")

through the walls of fuel hoses and fuel tanks. The permeation standards

apply to all classes of highway motorcycles.
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Background

This final rule follows EPA’s Notice of Proposed Rulemaking (NPRM)

published on August 14, 2002 (67 FR 53050) and supplemented by a

notice dated October 30, 2002 (67 FR 66097). We received comments on

the NPRM from a wide variety of stakeholders, including the motorcycle

manufacturing industry, motorcycle user groups, various governmental

bodies, environmental groups, and the general public. In the August

2002 NPRM, we also proposed new evaporative emission controls for

spark-ignition marine vessels. Spark-ignition marine vessels will be the

subject of a separate final action.

Federal regulations currently define a motorcycle as “any motor vehicle

with a headlight, taillight, and stoplight and having: two wheels, or three

wheels and a curb mass less than or equal to 793 kilograms (1749

pounds)” (see 40 CFR 86.402-98). Note that any motorcycle or motorcycle-like vehicle that falls outside that definition would be considered a

nonroad vehicle and be subject to different requirements.

Emission Limits

The following table shows the new exhaust standards for highway

motorcycles, including scooters and mopeds.

Highway Motorcycle Exhaust Emission Standards

We expect these standards to be met through an increased use of technologies already demonstrated as being effective on 4-stroke motorcycle

engines, such as secondary air injection, electronic fuel injection systems, and catalytic converters. The standards are not expected to result

in the universal use of catalytic converters.

Class

Engine Size

(cc)

Implementation

Date

HC (g/km) HC+NOx

(g/km) CO (g/km)

C 0 lass I l 6 ess than 17 2 0 00 1. _ 12.0

C 9 lass II 1 6 70-27 2 0 00 1. _ 12.0

Class III 280 and

above

2006 _ 1 0 .4 12.

2010 _ 0 0 .8 12.
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Health and Environmental Benefits

Nationwide, highway motorcycles are significant contributors to mobilesource air pollution and produce more harmful emissions per mile than a

car or even a large SUV. Motorcycles currently account for 0.6 percent

of mobile-source hydrocarbon (HC) emissions, 0.1 percent of mobilesource oxides of nitrogen (NOx) emissions, and less than 0.1 percent of

mobile-source particulate matter (PM) emissions. The highway motorcycle standards will reduce the combined emissions of HC and NOx in

the exhaust by 50 percent. Without these further regulations, highway

motorcycles would account for 2.2 percent of mobile source HC and 0.3

percent of mobile source NOx by 2020.

These standards will help reduce the public's exposure to these emissions and help avoid a range of adverse health effects associated with

ambient ozone and PM levels, especially in terms of respiratory impairment and related illnesses. In addition, the standards will help reduce

acute exposure to air toxics and PM for persons who operate or who

work with or are otherwise active in close proximity to these sources.

They will also help address other environmental problems associated

with these sources, such as visibility impairment in our national parks

and other wilderness areas.

It has been 20 years since EPA revised the motorcycle standards. In that

time, there have been many vehicle emission control technology advances. Since EPA has recently adopted emission standards for off-road

motorcycles as the result of a court order, this is an appropriate time to

update the highway motorcycle requirements.

The current federal motorcycle standard for hydrocarbon emissions is

about 90 times higher than the hydrocarbon standard for today’s passenger cars. Although many of today’s motorcycles will meet the current

California standards, the current California hydrocarbon standard is still

18 to 24 times greater than the current federal passenger car limits,

depending on the displacement of the motorcycle engine.

Beginning in 2004, all passenger cars, light trucks, and SUVs will be

required to meet even more stringent standards. When these standards

become effective, new SUVs will be meeting hydrocarbon standards

about 95 percent cleaner than today’s typical motorcycle.
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Costs

We project average costs of $30 per highway motorcycle to meet the

2006 standards and $45 to meet the 2010 standards. This increased cost

is partially offset by a discounted fuel savings of about $6.50 per motorcycle due to keeping more gasoline in the fuel tank.

For More Information

You can access documents on this rulemaking on EPA’s Office of Transportation and Air Quality Web site at:

www.epa.gov/otaq/roadbike.htm

For further information, please contact the Assessment and Standards

Division at:

U.S. Environmental Protection Agency

Office of Transportation and Air Quality

2000 Traverwood Drive

Ann Arbor, MI 48105

E-mail: ASDInfo@epa.gov

Voicemail: (734) 214-4636