Clutches – New machines have a thin layer of coated oil from the factory to protect them during travel and sitting in the crate and older machines probably are dusty and even worse if you did not put them away sparkling clean. Either way, it is time to take off the belt and wash it in hot soapy water. I have always used Sunlight soap but you can use Acetone as well. Next is to use a non-residue brake cleaner. Acetone or Ski-Doo special cleaner work well to clean the clutch sheaves and also the whole clutch area. Any machine that is not new should also be checked to ensure that everything is moving freely. See your local dealer if you are not an expert in this area.