Peak efficiency at 48V: 80 percent. Sprocket:for 8mm T8F chain.Note: This motor is capable of rotation in either the clockwise or counterclockwise direction by reversing the motor's power wires. Match motor: 48V 1000 W. Under Voltage Protection: 42±0.5V. Speed regulator (throttle): 1-4 V. This controller has 8 connectors, compatible with many 48V bikes with up to 1000W motors. Package: 1x motor + 1x controller + 1x chain + 1x throttle grips.