On certain snowmobiles, the primary (drive) clutch could fail. If this happens, pieces of the clutch could separate from the vehicle.
Safety Risk
Clutch parts that separate from the snowmobile could hit a person and create a risk of injury.
Corrective Actions
Yamaha will notify owners by mail and advise you to take your snowmobile to a dealership to install additional shielding around the primary clutch and the toe guard.