YAMAHA MJ rear sprocket for Yamaha TY 50 1978-1981 MJ Corse MJ.717 €38.24 High quality duraluminium (ergal) rear sprocket for Yamaha TY 50 1978-1981 with chain pitch 420 and with number of teeth from 30 to 52. Select the chain pitch and number of teeth you need by clicking below. Add to cart