Pulley Driven Wheel quotation Motorcycle pulley Driven Wheel Clutch Belt assembly. Fits most 50cc, 80cc, 100cc Chinese scooters. Compatible with all Chinese brand, like Taotao Roketa Sunl Kazuma Jonway Znen Redcat Eagle Xtreme Yiben SSR Vento. Compatible with GY6 50cc 4-stroke 139QMB engine with long or short case, suitable for GY6 QMB139 engine scooter, motorcycle, moped, ATV. Product Features Precise and stable, derived from professionalism, quick response, smooth acceleration, and restore the original vehicle power. The internal shaft on the back has been professionally polished, which is more wear-resistant, and the stroke is easier. The high-temperature quenching treatment of the welding point is high-temperature quenching, and the hardness is higher. Easily solve the problems of slipping, abnormal noise and vibration, making your travel safer. Product Parameters Outer Diameter (Pulley): 118mm Outer diameter (clutch bell): 115mm Inner diameter (clutch bell): 106mm Inner diameter (clutch): 12mm Use Clutch Bell with 6901-RS Bearings Inner diameter (peak to peak groove): 11mm Number of grooves (clutch bell): 22 Product Weight: 4.25 lbs Package Dimensions: 4.92 x 4.88 x 3.15 inches Pulley Driven Wheel quotation website:http://www.bsjmotoparts.com/motorcycle-engine-parts/pulley-driven-wheel/