Joe's trick makes the gear box very quiet and is very simple and nothing short of a miracle! During assembly, as the motor is slid into the plastic housing, the the motor is cocked at a small angle which slightly leans the motor shaft towards the propeller shaft. This reduces the gear mesh load. Be careful not to slide the motor in too far or the motor shaft may rub on the inside of the larger drum gear. Also, make sure the pinion gear is not rubbing on the side of the hole through the plastic housing.