Yamaha YZF-R125 Service Manual: Charging system

Troubleshooting

The starter motor fails to turn. NOTE: Before troubleshooting, remove the following part(s): 1. Seats 2. Fuel tank 3. Left lower side cowling 4. Left upper side cowling ...

Circuit diagram

1. AC magneto 3. Rectifier/regulator 4. Main fuse 9. Battery ...

Other materials:

Removing the starter clutch
1. Remove: Starter clutch bolts "1" NOTE: While holding the generator rotor "2" with the sheave holder "3", remove the starter clutch bolts. Do not allow the sheave holder to touch the projection on the generator rotor. ...

Troubleshooting
The ignition system fails to operate (no spark or intermittent spark). NOTE: Before troubleshooting, remove the following part(s): 1. Seats 2. Fuel tank 3. Right side cover 4. Left side panel 5. Left upper side cowling ...

Checking the rectifier/regulator
1. Check: Rectifier/regulator output voltage Out of specification → Replace the rectifier/ regulator. a. Set the engine tachometer to the spark plug lead. b. Connect the pocket tester (DC 20 V) to the rectifier/regulator coupler as shown. Positive tester probe red "1" Negat ...