1991-1993 Yamaha Exciter II-570 Service Manual, Page 306Get this manual
3Measure: Sheave offset Use the Sheave Gauge (-, YS-39506-1)Out of specification -; AdjustSheave offset: 14.5 17.5 mm (0.57
4Adjust: Sheave offset Adjustment steps: Apply the brake to lock the secondary sheave Remove the bolt (secondary sheave) and secondary sheave (D Adjustthe sheave offset by adding or removing shim(s)Adding shim Removing shim Part number 90201-252F1 90201-25527 90201-25526 Offset is increasedOffset is decreasedShim size Thickness 0.5 mm (0.02 in) 1.0 mm (0.04 in) 2.0 mm (0.08 in)