I have a shengyi hybrid bicycle electric motor... It's a 750 watt 48 volt unit ... it includes the brake rotor ... but no chain sprocket, it came off of a radwagon cargo bike ... (please Google).. very high quality unit in excellent condition... It was cheaper to buy a rim as a unit as opposed to just a motor ... this rim is bent hard... may be able to be fixed I don't know... this motor is in 100% working condition and only used for about a year on my bike... I have a complete rear wheel assembly on my bike and you can see and feel the power if you decide to buy it ... You can take my radwagon for a test drive.... any questions please ask... I can test motor for you