Better motorcycle emission controls are available and the EPA (Euro too) has been gradually phasing in tighter restrictions, so your point is moot. Every other measured pollutant (NOx, HCs, CO)is measured for a reason - its harmful and contributes to problems just like C02 does (which I never dismissed) - smog, asthma, etc. The point is a much smaller engine should also put out less of the other pollutants when its possible to control them.
Also most states regularly inspect the emission controls on gasoline passenger cars while motorcycles are exempt, so motorcycles will be even worse with time than passenger cars with no control on aging emission systems.
You can easily fault the corporations as some leave off emission controls in countries that don't require them on products with well developed controls like passenger cars. There are very few companies that haven't moved banned product to other markets when they knew they were harmful (US is the biggest producer of DDT) or moved all or most of their production to countries with lax pollution and/or labor laws. They are profiting at the expense of the people of those countries - they know better but profits go first.
Also most states regularly inspect the emission controls on gasoline passenger cars while motorcycles are exempt, so motorcycles will be even worse with time than passenger cars with no control on aging emission systems.
You can easily fault the corporations as some leave off emission controls in countries that don't require them on products with well developed controls like passenger cars. There are very few companies that haven't moved banned product to other markets when they knew they were harmful (US is the biggest producer of DDT) or moved all or most of their production to countries with lax pollution and/or labor laws. They are profiting at the expense of the people of those countries - they know better but profits go first.
Or it could be that it's really difficult to fit the equipment for tighter emissions controls within the very confined space of a motorcycle.
Also, nice dismissal of CO2 as unimportant. Guess global warming isn't a big deal? My little beemer got 70mpg and took 1/5 of the energy and materials to manufacture of, say, a prius, golf TDI, or civic hybrid. It also took up less space on the road and in the city, easing congestion. It spent zero time idling in traffic.
Could motorcycles be cleaner? Yes. Should they be? Yes. Is it some massive conspiracy led by the manufacturers to poison the populace? Sure, that's more likely than, say, the fact that motorcycles represent such a tiny proportion of traffic in the US that it's not worth the EPA or CARB's time to battle the highly vocal riders/populace over emissions. This is one of those rare cases where you can blame the people, not the corporations.
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