According to the National Highway Traffic Safety Administration, there are over eight million motorcycles registered in the United States. A significant percentage of motorcycles operating in the United States have been illegally equipped with after-market exhaust systems which are not EPA-compliant.
In its analysis for the noise emission regulations for motorcycles and motorcycle exhaust systems, the United States Environmental Protection Agency concluded that a significant portion of the problem of excessive motorcycle noise was due to motorcycles with after-market exhaust systems and to tampering with the original equipment exhaust system. That problem persists today, and if anything, has grown worse and is the root cause of excessively loud motorcycles.
The EPA stated that motorcycles with either modification listed above could easily increase noise emissions to over 100 dBa. They also realized that although motorcycles only account for two or three percent of total vehicular traffic mileage, and because they are presently among the noisiest vehicles in the traffic stream, any reductions in motorcycle noise would have a significant impact upon overall traffic noise and benefit the public.
A mere one hour of exposure to noise levels at 94 decibels can damage your hearing. If the noise is 100 decibels, it only takes 15 minutes for hearing damage to occur. But hearing damage is not the only adverse effect excessively loud motorcycles have on the public. Unlike legally equipped and quiet motorcycles, the excessive noise of many illegally modified motorcycles can be heard for miles. Excessive motorcycle noise poses a severe public nuisance and health hazard and adversely impacts the public's quality of life.
According to a Motorcycle Industry Council's 2008 Owner Survey, 38% of on-road motorcycle owners replace or modify their exhaust systems. Cruisers are the most common type of bike with a modified exhaust, followed by sport bikes, touring models, and competition dirt bikes.
The California Air Resources Board reports the following: "One of the more popular modifications today is replacement of the original exhaust system with aftermarket exhaust systems and parts."
And according to a California Air Resources Board survey of 2003 to 2007 model year highway motorcycles, "85 percent of newer motorcycles in Southern California (primarily Harley Davidsons) had some form of exhaust modification. After-market exhaust systems on highway motorcycles can range from straight pipes without any catalysts to systems with catalysts that have not demonstrated durability and/or the ability to effectively control emissions."
The large displacement V-win motorcycles manufactured by Harley-Davidson are among the most commonly modified with the use of after-market non-EPA compliant exhaust systems. Not surprisingly, they are also among the loudest motorcycles on the road and elicit the bulk of citizen complaints about motorcycle noise. "We usually see 60 to 70 percent of riders change the pipes out," according to the general manager at a Boston Harley-Davidson dealership. But motorcycles made by Harley-Davidson are not the only motorcycles being illegally modified to make noise; the problem is present with other brands of motorcycles as well.
It is very clear that there are many loud motorcycles in the United States. It is also very clear why so many on them are loud: they have been illegally modified. Also, the solution to the problem is not too difficult to deduce. The laws and regulations prohibiting those unlawful acts must be enforced.
Addressing The Problem
The role of the federal government
The role of the federal government is to establish noise pollution regulations where necessary. In the 1980's, when the EPA's Office of Noise Abatement and Control (ONAC) was in operation, it established noise emission limits for highway and off-road motorcycles. The purpose of those regulations was to provide a minimum of protection to the public from excessive motorcycle noise and to establish a national uniformity of treatment for the that source of noise pollution.
Lack of federal enforcement
In spite of the Noise Control Act of 1972 and Subparts D and E of Part 205 of Title 40 of the Code of Federal Regulations, the EPA is currently taking little or no action against illegal motorcycle noise. The EPA's standard response to noise pollution related inquiries is that dealing with noise pollution "is best left to the states" and cites "lack of resources" as an excuse not to enforce federal noise pollution regulations.
By the "lack of resources" response, the EPA is referring to Congress defunding its Office of Noise Abatement and Control in 1981. In effect, the EPA is claiming that Congress is not allowing it to regulate noise pollution or enforce the Federal noise pollution regulations that are still on the books and in effect. Because of that bad policy decision by Congress, the EPA does not currently see noise pollution to be within its purview and remains inert in carrying out the intent of the NCA of 1972. The result of that bad policy: out of control and ever-escalating noise pollution. And in the case of motorcycles, an out of control motorcycle noise pollution problem.
We disagree with Congress's and the EPA's position on the noise pollution issue and on the EPA's excuses for not enforcing any federal noise pollution regulations at all. That policy must be changed. That will require lobbying Congress to direct the EPA to include noise pollution within its purview, provide funding for enforcing and revising at least one federal noise pollution regulation: 40 CFR 205, parts D&E (the federal motorcycle noise and muffler regulations).
Is it really best to leave noise pollution control entirely up to the states? No. Ever since Congress defunded the federal noise pollution control program, the states have done nothing to take up the slack. Without federal assistance and involvement, the states terminated their noise pollution control programs and their efforts to enforce their motor vehicle noise and mufflers are weak.
It is vitally important for the federal government do its part in making sure the motorcycle industry complies with the federal manufacturing regulations for motorcycles and make sure the industry is manufacturing legal EPA-compliant mufflers for motorcycles. That is something the states cannot do and where federal action is essential.