2003 Polaris ATV Trail Boss 330 Factory Service Manual, Page 131Get this manual
DRIVE BELT REMOVALINSPECTION
1Remove outer PVT cover as described in PVT Disassembly2Mark drive belt direction of rotation so that it can be installed in the same directionNOTE: Normally positioned so part numbers are easily read
4Measure belt width and replace if worn severelyGenerally, belt should be replaced if clutches can no longer be adjusted to provide proper belt deflectionG The top edges have been trimmed on some drive beltsIt will be necessary to project the side profiles and measure from corner to cornerG Place straight edge on each side of the drive beltG Place another straight edge on top of beltG Measure the distance where the side straight edges intersect the top, as shown in the illustration below5Inspect belt for loose cords, missing cogs, cracks, abrasions, thin spots, or excessive wearReplace if necessary6Inspect 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