We can be even more thankful for our little Buddy's
The Little Engine That Could, Maybe
Two-stroke engines are the cockroaches of the motorized world. You see
them--and hear them and smell them--in products ranging from leaf blowers
and lawn mowers in Beverly Hills to chain saws in Sweden to motorboats in
Bolivia to millions of little motor scooters in China, India, and the
Pacific Rim. While four-stroke automobile engines get most of the
attention from regulators who set emissions standards, the little
two-bangers have a greater impact on global pollution because there are so
many of them and because they are noisy and noisome and less fuel
efficient. One old two-stroke motor scooter in Beijing puts more pollution
into the atmosphere than a dozen or more new automobiles on the Los
Angeles freeway. And because the vehicles are ubiquitous—there are an estimated 50 million to 100 million two-stroke two- and three-wheelers throughout South Asia—the pollution from these bikes is equal to as much as 5 billion midsize automobiles. On streets choked with tricycles, the air above is choked with smog. The World Bank estimates that air pollution from Philippine two-stroke engines accounts for as many as 2,000 premature deaths a year. To put this into perspective, automobile emissions are nearly 1000 times lower, even though each automobile on the road is operated up to 1000 times longer than each two-stroke engine.
Two-stroke engines are less fuel efficient and pollute more than 4-stroke engines. For example, a personal watercraft that uses a 70-horsepower, two-stroke outboard motor, emits the same amount of hydrocarbon pollution in one hour as the engine of a new car would if it were driven 8,000 kilometers.
Lawnmowers Did you know that a conventional gasoline lawnmower pollutes as much in an hour as 100 modern cars !
