These replacement AEG motor brushes from Bravo are the best option for an older, worn motor. With use, airsoft motors can wear out. The Bravo Motor Brush replacement set can reinvigorate an worn out motor.
This set includes two AEG motor brushes, which fit all brand motors. They include a screw-on terminal for best efficiency, but the terminal can be clipped and the wire twisted on like most stock motors.