DRC Rear Sprocket 520 D6387 Aluminium for Yamaha DRC DRC rear sprocket D6387. See if it fits your bike. Yamaha WR 250 F Yamaha WR 250 R Yamaha WR 250 X Yamaha WR 400 F Yamaha WR 450 F Yamaha YZ 125 Yamaha YZ 125 X Yamaha YZ 250 Yamaha YZ 250 F Yamaha YZ 250 FX Yamaha YZ 250 X Yamaha YZ 400 F