ANALYSIS: EPA Streetbike Emission Standards

The EPA revised national emissions standards for new road motorcycles would require bikes to meet strict emissions standards beginning with 2006 models and even more strict standards beginning in 2010.

The new standards are expected to result in an increased use of fuel injection and catalytic converters on new motorcycles. Some motorcycles sold in the United States already meet California’s strict 2008 standards, which are the same as the planned federal EPA 2010 standard.

The current federal emissions standards for street motorcycles are 5.0 grams of hydrocarbons and 12 grams of carbon monoxide per kilometer traveled.

Phase 1 would go into effect in 2006.
Similar to the new California Standard (that begins with the 2004 model year), the planned Phase 1: federal national standard would take effect for model year 2006, and require new road-going motorcycles to emit no more than 1.4 grams per kilometer traveled of hydrocarbons and nitrogen oxides and 12 grams per kilometer of carbon monoxide.

Phase 2 would be in place for 2010.
The California standard for 2008, that would also be the national standard beginning in 2010, sets a limit of 0.8 grams per kilometer of hydrocarbons and nitrogen oxides and 12 grams per kilometer of carbon monoxide.

Concerning off-highway motorcycles and all-terrain vehicles, the EPA announced in September new emissions standards that would be partially phased-in in 2006. Full compliance would be required by the manufacturers in 2007.


The EPA has decided to cause new regulations on motorcycles simply because they haven’t been lowered in 20 years. However, EPA figures state motorcycles emit less than 1% of all mobile source emissions! The cost and impact to the motorcycle communicty (manufacturers, after-market and consumers) needs to be scientifically weighed against how much pollution will be reduced by such efforts and costs. Said another way, the cost of proposed standards must be verified to be scientifically possible and cost effective.



If the EPA and CARB staffs are WRONG and the manufacturers can not deliver acceptable certifiable replacements for the popular models we all now buy, use and enjoy, there will be serious product shortages. Not all motorcycle engine designs and platforms perform optimally, or even adequately, with catalysts and fuel-injection.

The 2008 standards almost eliminates most models without these technologies. Motorcycles will become more and more complicated, discouraging legal performance modifications or even servicing by owners. It’s too big a gamble to accept the EPA’s proposed emission standards that result in little or no air quality improvement. After all, that’s supposed to be the justification for lower emissions standards, not just because the EPA standard hasn’t changed for over 20 years, and Calif., has a lower one.