We often talk in Snow Goer magazine and on snowgoer.com about how important it is to scuff the sheaves of snowmobile clutches in order to achieve the best performance from a snowmobile.
Rubbing (lightly) a piece of 150-grit emery cloth on the sheaves removes the glaze and belt debris that’s embedded in the metal. This provides a good surface for the belt to gain more traction so it can transfer the engine’s power to the ground more efficiently. But scuffing the sheaves is only part of the job.
After you’ve rubbed the sheaves as part of your snowmobile clutch maintenance regimen, be sure to wash the clutches so the metal dust doesn’t get into the clutch’s rollers and bushings and accelerate wear. It’s best to rinse the clutches with warm water, as this is the most thorough way to flush out the metal debris and belt residue.
If that isn’t possible, spray the clutch with brake cleaner to flush out the debris and then wipe it with a clean cloth. Compressed air might work well, too, but make sure you don’t blow the dust further into the clutch’s inner workings. After the clutch is clean, scuff the belt’s sidewalls with emery cloth and set the belt deflection. You’ll be amazed at how much the sled’s holeshot improves!