Motors with brushes, mounted in a housing through which is fixed to the car, where he has anchored the two magnets acting magnetic pole. Inside the rotor is surrounded by a wire called winding is at, thickness and number of turns of the cable determine engine performance. The shaft exiting one end serves to place the transmission pinion. They are easily recognizable because they carry only two wires to connect the drive. You need to keep this part of the car always clean and avoid direct humidities.