Environmentally Friendly Motorcycles | It's Not Easy Being Green | Answers

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I've been reading a lot about electric motorcycles, and I'm not convinced they provide the capabilities I want right now. I rode 10,000 miles across the USA and Canada this summer, and I can't imagine doing that on an electric bike any time soon. I've concluded that I'll be riding motorcycles like my BMW R1200RT and Triumph Bonneville T100 for many more years. So, it would be nice if my gaspowered motorcycle were as environmentally friendly as possible. I'm wondering why motorcycles aren't more environmentally friendly. Yes, bikes get better gas mileage than the typical car, and even produce less carbon dioxide. However, they produce signifcantly more carbon monoxide, hydrocarbons and nitric oxide. Given the signifcant interest in "green" everything, it would seem that motorcycle manufacturers would put more emphasis on reducing emissions.
Bryan Knysh
Saratoga, CA

In addition to decades riding on the street and in the dirt, Pete Sullivan has more than 30 years in the automotive repair business, including inventing some emissions testing machines. We showed him your letter, and he explained that there are a number of reasons why motorcycles are less “green” than automobiles.

_In car terms, any performance motorcycle engine is a high-revving hot-rod. Cars are routinely limited by their ignitions to cut out at 6000 rpm, while bikes spin to 9000 rpm or higher. Cars need to make torque to move so much mass, but have powerbands that make effcient power for only 2000 rpm. Motorcycles need to make torque and horsepower over a wider rpm range. _

Oxides of nitrogen are handled by a car’s exhaust gas recirculation (EGR) valve, but that’s hard to employ on high-revving motorcycles. A big part of the problem is packaging. Even a small car has a lot of room to package emission controls. A motorcycle doesn’t have much room for those components, or the large catalytic converters that autos employ. As far as which motorcycles are “greenest,” look for those with fuel-injection, catalysts and an effcient engine that doesn’t turn a lot of rpm.