Remove the Starter Motor, Chinese Import 4 Stroke Scooter QMB139

You should be able to source a replacement starter motor from most good scooter dealers. Also, due to the cheap construction of Chinese imported 50cc scooters, it is possible to open the starter motor up and clean/check all the connections.

1. Place your motorbike on its center stand. In these pictures I have removed some bodywork for camera access, this is not always necessary.
2. The starter motor can be found on top of your QMB139 engine, in front of the rear wheel. It is bolted to the transmission by two 8mm bolts.
   
   
3. Now, undo the two 8mm bolts. Access is easiest from the other side of the scooter using a ratchet and long extension bar.
4. You can now pull the starter motor out from the transmission, through the motorbike and out above the exhaust.
   
   NOTE: The starter may be stuck in the transmission due to corrosion. Use a flat bladed screwdriver to lever the motor out if this is the case.
5. Once you have the starter motor out of the 50cc 4 stroke scooter, you can disconnect the 12v supply. This is normally secured to the motorcycles starter by a cross head screw.
   
   
6. You can now test the starter motor using an external 12v source, strip the starter motor to fix it or simply throw it away and replace it.
7. Reverse this procedure to refit the starter motor. Make sure you clean any corrosion from the 12v connector and the starter motor casing, pay particular attention to areas that contact the transmission as this is how the starter motor is connected to the Ground.