The most reasonably priced component used on the Xt500 1981 Dual Purpose Usa Clutch is the Pin (558).
Parts such as the Clutch: Spring, Plate, Thrust (2), Oil Seal (48u), Washer, Plate 3412175700 are included in the Xt500 1981 Dual Purpose Usa Clutch parts fiche.
The most expensive part in this assembly is the Primary Driven Gear Comp..
