The noise and pollution that snowmobiles cause is leading the National Park Service in Yellowstone National Park to look for relief.
This past winter, park workers tested more environmentally friendly, but less powerful, four-stroke machines produced on a test basis by a Minnesota snowmobile manufacturer. Machines currently on the market are built with a two-stroke engine that uses more fuel and produces more exhaust, but provides the power needed for racing and driving through deep snow.
The experimental engines may eventually find a market niche, though. Manufacturers say they would be appropriate for touring and family trail riding. And as the snowmobiling population ages and more environmental regulations govern the use of snowmobiles, the less powerful but more fuel-efficient models may grow in popularity.
The U.S. Environmental Protection Agency is expected to release emission standards in fall on motorized personal recreational vehicles, which also may encourage more extensive production of a new snowmobile model.
