2007 Polaris Two Stroke Snowmobile Workshop Repair manual, Page 67Get this manual
MAINTENANCE Belt Deflection Inspection
Belt deflection is critical for optimum belt performance and belt lifeIt should be checked at 500 miles (800km) and then in 1000 mile (1600km) increments after thatToo much belt deflection is when the belt is too long or the center distance is too shortThe initial starting ratio will be too high, resulting in performance lossThis is due to the belt rising too high in the drive clutch sheaves upon engagement (A)Not enough belt deflection (B) is when the belt is too short or the center distance is too longThe initial starting ratio will be too lowIn addition, the machine may creep when the engine idles, causing damage to the internal face of the drive belt