2003 Polaris Deep Snow Snowmobiles Service Manual, Page 202Get this manual
DRIVEDRIVEN CLUTCHES Drive Belt Inspection
1Measure belt width and replace if worn severelyGenerally, belt should be replaced if clutches can no longer be adjusted to provide proper belt deflectionS The top edges have been trimmed on some drive beltsIt will be necessary to project the side profiles and measure from corner to cornerPlace straight edge on each side of the drive beltPlace another straight edge on top of beltMeasure the distance where the side straight edges intersect the top, as shown in the illustration at rightProjected Belt Width
2Inspect belt for loose cords, missing cogs, cracks, abrasions, thin spots, or excessive wearReplace if necessary3Inspect belt for hour glassing (extreme circular wear in at least one spot and on both sides of the belt)Hour glassing occurs when the drive train does not move and the drive clutch engages the belt
Belt WearBurn Diagnosis