New EPA Emissions Rules May Mark End Of Two-Strokes

Sept. 27. 2002. The U.S. Environmental Protection Agency is adopting strict emissions standards that could mean the end of two-stroke trail bikes and All-Terrain Vehicles (ATVs) by 2006.

In announcing the new emissions standards in September, the EPA said the rules “encourage manufacturers of these vehicles to switch from two-stroke engines to cleaner four-stroke engines, beginning in 2006” for trail machines.

The federal agency is exempting racing machines from the strict emissions standards, so motocrossers won’t be affected, and left the door open for the production of a new breed of two-stroke engines by creating a special, less-stringent emissions standard for “certified competition machines” that could be used for competition and trail riding.

The EPA also scrapped an earlier plan to make ATVs meet even stricter emissions standards in 2009.

These are the first federal emissions standards created for off-highway motorcycles and ATVs. The EPA has set requirements only slightly less stringent than those in place in California, which have severely restricted two-stroke off-highway machine use there.

National requirements for road motorcycles have been in place for more than 20 years and are in the process of being replaced with stricter standards.

Under the new EPA rules, new trail bikes and ATVs would be subject to strict emissions requirements that would be partially phased-in in 2006. Full compliance would be required by the manufacturers in 2007.

The requirements wouldn’t affect machines built through 2005, but would apply to machines built for the 2006 model year and thereafter. The EPA said it expects that manufacturers will meet these new standards for trail machines by using four-stroke engines.

When the EPA was putting together the new rules, the AMA urged the agency to avoid regulations that would eliminate two-stroke machines, which are favored by many off-highway riders for their light weight and power characteristics. Instead, the AMA told the agency to consider creating separate emissions standards for four-stroke and two-stroke motorcycles and ATVs.

While the EPA rejected the idea of separate standards for four-strokes and two-strokes, it did create a new classification called the “certified competition machine,” which could be used for competition or trail riding. The emissions standards for a certified competition machine aren’t as strict as those for a trail bike or non-competition ATV. Theoretically, this could become the standard for two-stroke trail motorcycles and ATVs.

The AMA also asked the EPA to set specific emissions goals that must be met by off-highway motorcycle and ATV manufacturers rather than mandating what equipment must be on the bikes, such as catalytic converters. The EPA agreed.

The AMA also told the EPA to reconsider an idea to restrict the sale of “competition-only” machines to professionals. The AMA noted that most off-highway motorcycle and ATV racing in the United States involves amateurs. The EPA agreed in its final rules, saying it would be “inappropriate” to limit competition machines to professional racers.

Finally, the AMA and others involved in motorcycling presented data to show that the EPA grossly overestimated the annual use of off-highway motorcycles and ATVs and, as a result, overestimated the amount of pollution they cause. The EPA agreed, and that’s at least part of the reason the agency decided at this time not to require ATVs to meet even stricter emissions requirements beginning in 2009.

The AMA and the All-Terrain Vehicle Association (ATVA) ask all motorcycle and ATV riders to vote in the Nov. 5 general election to protect their right to ride.

Voters nationwide will be electing candidates to offices ranging from every seat in the U.S. House and one-third of the Senate to state legislatures and township councils. Motorcycle- and ATV-friendly officials in those offices can have an enormous impact on issues such as rider education, off-highway vehicle recreation areas, or even whether motorcycle or ATV enthusiasts can ride on their own private land.

“It’s important that motorcyclists and ATV riders get to know the candidates before stepping into the voting booth on Nov. 5,” said Terry Lee Cook, AMA state programs manager. “We don’t expect people to vote on a candidate based on a single issue, but we want voters to consider a variety of issues important to them before casting a vote. “You won’t find motorcycling and ATV issues spelled out in candidates’ campaign literature,” Cook added. “So voters have to ask candidates questions, either at town hall meetings or even by calling a candidate’s campaign headquarters, to get answers.” Voters can find out whether they are registered to vote and who the candidates are by contacting the local county Board of Elections.


The American Motorcyclist Association is a 270,000-member nonprofit organization. Established in 1924, the Association’s purpose is to pursue, protect and promote the interests of motorcyclists, while serving the needs of its members. For more information, visit the AMA website at