Parts such as the Rear Wheel: Washer,spring,6mm, Adjuster,sr.chain, Tube,tire, Tube 350-8 Tr-87 are included in the Z50r 1987 (h) Usa Rear Wheel parts fiche.
Check out any of the thirty-five Rear Wheel components enlisted.
The most reasonably priced component used on the Z50r 1987 (h) Usa Rear Wheel is the Washer,plain, 6mm.