A chainsaw and a drive system therefor are provided. The drive system includes a motor operably coupled to drive a motor shaft and an output drive operably coupled to an output shaft. The motor shaft and the output shaft are mechanically coupled to one another by a transmission system to transfer energy from the motor to the output drive. The motor and motor shaft are coupled to a housing. The transmission system allows the output shaft to selectively change positions along a circumferential direction relative to a rotational axis of the motor shaft to selectively loosen or tighten a connection of the output drive to a chain at a guide bar.