Clutch assembly is the centrifugal clutch for many go-karts and mini bikes. Clutch details: 5/8 Bore 11 Tooth / Teeth Used with #35 chain Known to fit 2hp and 3hp engines with 5/8" shafts. Tao Tao ATD80A and GK80. Also the Motovox MBX10 and MBX11 mini bikes. Check pictures and measurements to be sure this is the correct clutch for your application.