A motor system designed to replace and internal combustion engine. The motor system may include an electric motor and a battery that provides power to the electric motor. The system may also include control electronics to control the battery discharge current. The battery discharge current may be a relatively low current if the motor speed is less than a first threshold. The battery discharge current may be a relatively high current if the motor speed is greater than the first threshold but less than a second threshold. The battery discharge current may be the relatively low current if the motor speed is greater than the second threshold but less than a third threshold.