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Noise Control of Pre-Regulation Motorcycles

When a state recognizes and enforces the Noise Control Act and the EPA’s motorcycle and motorcycle exhaust system noise emissions regulations, it will be utilizing the highest standard of motorcycle exhaust system technology.

One can easily reason that if a motorcycle muffler cannot meet EPA noise emissions standards and is easily identifiable by design characteristics (i.e., straight pipe, hollow-core muffler, or mufflers labeled for competition use), then it should not be permitted on any motorcycle regardless of year of manufacture. This can easily be accomplished by adding the following to state vehicle law:

Every motorcycle, regardless of year, shall be equipped with an adequate muffler in constant operation, free of defects and modifications, that prevents the escape of any excessive or unusual noise. The muffler, if not originally equipped, must reduce exhaust noise levels to that of the vehicle’s original equipment. No motorcycle shall be equipped with a straight pipe exhaust system (regardless of the presence of baffles), a hollow-core muffler, or a muffler that is labeled for off-road closed-course competition use. No motorcycle shall be equipped with a cutout, bypass, or similar device.

We include detailed photos, descriptions, and definitions of these types of loud aftermarket exhaust systems and mufflers listed above. However, there are still aftermarket mufflers that are ineffective and cannot be identified or classified by the definitions of these prohibited exhaust systems and mufflers.

These poor examples of mufflers can be kept off of pre-federal regulation motorcycles by use of the adjectives “adequate,” “excessive,” and “unusual” in the description of mufflers in the statute language.

This method of noise control is referred to as a “qualitative” standard. The courts over the years have found this method and statute language to be constitutionally sound^[1] and not vague, as it clearly provides a standard for vehicle owners to meet in order to be in conformity with the law. At least fourteen states already use this method and similar language in their vehicle codes.

CA, AR, CO, DE, KY, LA, MO, NY, ND, NC, RI, WI, WV, and WA have vehicle muffler equipment laws based on this qualitative standard. Many of these states require mufflers with noise suppression characteristics similar to the vehicle’s original equipment, or require “adequate” mufflers that prevent the escape of “unusual” or “excessive” noise.

Although this “qualitative” method of noise control may appear to be adequate to control noise emissions for all years of motorcycles, it has the disadvantage of being based on a police officer’s opinion. This may be sufficient for the small number of motorcycles made before 1983 that are still on the road today, but for the fleet of newer motorcycles manufactured after 1983, the “label match-up” provides a much simpler and more precise method of noise control.

Annotation, “Validity, Under Federal Constitution, of Federal, State or Local Antinoise Laws and Regulations,” 36 L. Ed. 2d 1041 (1973).