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:

Checking the connections
Check the leads, couplers, and connectors for stains, rust, moisture, etc. 1. Disconnect: Lead Coupler Connector 2. Check: Lead Coupler Connector Moisture → Dry with an air blower. Rust/stains → Connect and disconnect several times. 3. Check: All co ...

Checking the spark plug cap
1. Check: Spark plug cap resistance Out of specification Replace. a. Remove the spark plug cap from the spark plug lead. b. Connect the pocket tester ( × 1k) to the spark plug cap as shown. c. Measure the spark plug cap resistance. ...

Separating the crankcase
1. Remove: Crankcase bolts NOTE: Loosen each bolt 1/4 of a turn at a time, in stages and in the proper sequence as shown. A. Right crankcase B. Left crankcase 2. Turn: Shift drum segment NOTE: Turn the shift drum segment "1" to the position shown in the illustration. In this ...