Our company can product the motor in diameter can be from 55 mm to 108mm Voltage from 6 volts to 110 volts Power from 10 watts to 1000 watts, Speed change from 300 to 6000. 1.Specification:350W24V 350W36V No-load speed:3000rpm Load speed:2650rpm Output torque:1.26N.m 2.Specification:500W36V 500W48V No-load speed:3300rpm Load speed:2900rpm Output torque:1.65N.m 3.Specification:650W36V 650W48V No-load speed:3600rpm Load speed:3100rpm Output torque:2.0N.m