Inspect the belt & clean your clutches
With the belt in hand, carefully examine for damage and wear. Look closely at the sidewalls for exposed cords and thin spots. Inspect the top and bottom surfaces for cracks and delamination. If the belt shows any of this wear or damage, it should be discarded and replaced with a new one.
Belt sidewalls that are shiny and glazed but otherwise look OK can be rehabilitated by lightly scrubbing with a wire brush or by sanding with a piece of emery cloth. Inspect the clutch faces, too, because they will also be glazed.
Glaze is a condition that contributes to belt slip, which causes a loss of performance and increased wear to the belt and clutch faces. Use light hand pressure with emery cloth or a scuff pad like Scotch-Brite to remove the glaze from the faces of both clutches.
After removing the glaze, wash the clutches with warm, soapy water, and then wipe the faces with a clean shop towel that’s been soaked with isopropyl alcohol or acetone. This will ensure all belt residue and abrasives have been flushed away. Have an experienced snowmobile mechanic inspect the clutch weights, bushings, rollers and springs.