... frequency quenching,Carburization Sandblasting,Galvanized,Cr-plating..etc motorcycle Sprocket and chain1) Material:45# steel,16 # Mn,A3 steel2) Specification: ... 415,420,428,428H,520..etc3) Front gear:13T,14T,15T,16T,17T..etc4) Rear gear:34T,35T,36T,37T,38T,57T ... welcomed.Good quality guatantee with competetive price.Expecting your contact and visit us for more information!Our main sprockets types. ...