i also found this @
http://www.amadirectlink.com/magazine/2001/story3dec.htmBye Bye Two-Strokes?
New EPA rules could eliminate a whole
class of trail bikes by 2006
Is this the end of the trail for two-stroke bikes?
It seems likely.
The federal Environmental Protection Agency has proposed new regulations that would, for the first time, place limits on emissions from off-highway motorcycles and ATVs. And those regulations, which may become law early next year, could effectively outlaw two-stroke trailbikes beginning with the 2006 model year.
While the rules don’t specifically ban two-strokes, EPA officials have made it clear that they anticipate that will be the outcome of this set of regulations. Indeed, the agency believes that two-strokes will disappear from the trails just the way they disappeared from the streets a couple of decades ago following the imposition of emissions regulations on road bikes.
This is obviously a major development, with enormous implications for everyone who rides in the dirt. So here’s everything you need to know to understand this ruling:
First, this set of regulations does not cover all dirtbikes. It makes specific exceptions for “off-road competition-only machines,” vehicles “lacking lights or a spark arrester, having suspension travel of more than 10 inches, and having an engine displacement larger than 50cc.” In other words, if you race a motocross bike on an MX track, you’ll be unaffected.
In addition, manufacturers could legally continue to sell two-stroke motorcycles which don’t meet that description if they can convince the EPA the machines would be used solely for competition. In theory, this might leave open a loophole for bikes used in desert racing, hare scrambles and enduros.
Also, since the proposed regs would only affect new bikes, anyone can continue to ride motorcycles already approved for trail use.
So what does that leave? Mostly, motorcycles and ATVs that will be purchased in the future by recreational trail riders, which is still a very large percentage of the off-road market. And, although four-stroke bikes have made serious inroads into this market in the recent years, two-strokes remain popular among many riders for their light weight, their simple design and their power characteristics.
How strict are the regulations? Well, there’s some good news there. When the emissions standards were in the discussion stages, the EPA was talking about the possibility of setting specific equipment rules: a ban on two-strokes, requiring catalytic converters, that sort of thing. The AMA asked the agency to simply set performance regs and let the manufacturers decide how to meet them, and that’s what the agency has done.
However, we also asked the agency to set separate standards for two-stroke and four-stroke bikes, and it chose not to.
Can two-strokes somehow survive under the same regulations as four-strokes? It doesn’t appear likely at this time.
EMISSION STANDARDS HC NOx
g/km* CO
g/km*
Proposed federal off-road motorcycle standards beginning in 2006 2.0 25.0
Existing California off-road motorcycle standards 1.2** 15.0
Existing federal streetbike standards 5.0** 12.0
*HC NOx- Hydrocarbons and Oxides of Nitrogen CO-Carbon Monoxide g/km - In grams per kilometer
**Hydrocarbons only
Sources: U.S. Environmental Protection Agency, California Air Resources Board
The EPA is calling for emissions limits of 2 grams per kilometer traveled for hydrocarbons and oxides of nitrogen, and 25 grams per kilometer for carbon monoxide. That’s slightly less strict than off-road rules that went into effect in California in 1997 (see chart right), where the limits are 1.2 grams per kilometer for hydrocarbons and 15 grams per kilometer for carbon monoxide (California doesn’t regulate oxides of nitrogen).
For purposes of comparison, the current regulations governing road motorcycles are 5 grams per kilometer for hydrocarbons and 12 grams per kilometer for carbon monoxide. However, those standards were adopted 23 years ago, and the EPA has said it will propose new, stricter standards for streetbikes about the time you receive this issue. Expect a story on developments there next month.
The California standards have resulted in the virtual elimination of two-stroke machines from the trailbike market there, and the EPA clearly believes these regulations will have the same effect nationwide.
The agency does note that off-highway two-strokes could be made to meet the new emissions standards by using direct fuel-injection systems, like those being developed by Orbital Technology, and catalytic converters. However, the EPA notes, “there are several issues associated with direct injection, such as system durability and the need for high electrical-system output, that need to be resolved before it can be successfully integrated into off-highway motorcycle and ATV applications.”
“For these reasons, and because of the potential complexities and cost of a direct-injection system, we anticipate that most manufacturers would chose to convert models using two-stroke engines to four-stroke engines.’’
In other words, the EPA believes that if you ride a two-stroke trailbike now, there’s a four-stroke in your future.
How far in the future? The off-road standards, if adopted, would be partially phased-in for 2006, with 100 percent compliance required by 2007. In addition, ATVs would be required to meet even tougher standards beginning in 2009.
Until that time, manufacturers can continue to sell two-stroke machines designed for trail use. And owners of such machines could continue to use them legally even after the new standards go into effect.
As we noted earlier, a large percentage of the bikes being built for trail use are already four-strokes, so it may not seem that there’s much of a change here. Under the surface, though, there are major implications for many two-stroke riders.
Until now, the owner of a motocross bike could equip the machine with a spark arrester and an exhaust system meeting the requirements of the Forest Service or the Bureau of Land Management and legally ride it on trails administered by those two agencies. Indeed, at one time, Suzuki and Yamaha both built trail versions of motocross bikes by adding this equipment.
But with the advent of these regulations, off-highway motorcycles will be put in two different classifications. Those built for trail use will be designed to meet the standards, while those built for competition use will not. That’s likely to mean that individual users will have no way to convert an MX bike to make it legal for trail riding.
This is already the case in California, where the existing “green sticker” registration program for off-highway bikes has spawned a new competition variant. Motocross bikes still can be registered, but they receive red stickers, rather than green stickers, meaning they can only be ridden on public land during certain seasons.
Theoretically, the EPA’s proposed regulations would mean that anyone riding a motocross bike made after 2006 on public trails could be stopped and ticketed by a ranger. But as in California, the major enforcement is likely to come when a rider attempts to register a bike for trail use. Although standards vary enormously across the country, it’s likely that states will gradually adopt rules that require a bike to meet the new EPA standards before it can be registered for trail use.
It all adds up to enormous changes for many recreational trail riders across the country. If you’re one of them, and you have concerns about the direction the EPA is going, this is the time to speak up.
The AMA has prepared a response to the EPA proposal that you can send in your name by going to the Rapid Response Center. The Center also offers more background on this issue.
You can also respond to these proposed rules until December 19 by writing to: Margaret Borushko (Docket No. A-2000-01), U.S. Environmental Protection Agency, Office of Transportation and Air Quality, 2000 Traverwood Drive, Ann Arbor, MI 48105; or submitting comments by e-mail to:
nranprm@epa.gov.
© 2001 by the American Motorcyclist Association