Yamaha YZF-R125 Service Manual: Shift shaft

Installing the oil pump

1. Install: Oil pump assembly CAUTION:After tightening the screws, make sure the oil pump turns smoothly. ...

Checking the shift shaft

1. Check: Shift shaft Bends/damage/wear Replace. Shift shaft spring Damage/wear Replace. Checking the stopper lever 1. Check: Stopper lever Bends/damage Replace. Roller ...

Other materials:

Checking the shift drum assembly
1. Check: Shift drum groove Damage/scratches/wear Replace the shift drum assembly. Shift drum segment "1" Damage/wear  Replace the shift drum assembly. Shift drum bearing "2" Damage/pitting Replace the shift drum assembly. ...

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 ...

Checking the crankshaft position sensor
1. Disconnect: Crankshaft position sensor coupler (from the wire harness) 2. Check: Crankshaft position sensor resistance Out of specification  Replace the crankshaft position sensor/stator assembly. a. Connect the pocket tester ( × 100) to the crankshaft position sensor c ...