Yamaha YZF-R125 Service Manual: Electric starter

Installing the generator

1. Install: Woodruff key Generator rotor Washer Generator rotor nut NOTE: Clean the tapered portion of the crankshaft and the generator rotor hub. When installing the generator ro ...

Checking the starter motor

1. Check: Commutator Dirt Clean with 600 grit sandpaper. 2. Measure: Commutator diameter "a" Out of specification Replace the starter motor. 3. Measure: Mica under ...

Other materials:

Checking the bulbs and bulb sockets
NOTE: Do not check any of the lights that use LEDs. Check each bulb and bulb socket for damage or wear, proper connections, and also for continuity between the terminals. Damage/wear  Repair or replace the bulb, bulb socket or both. Improperly connected Properly connect. No c ...

Checking the piston rings
1. Measure: Piston ring side clearance Out of specification Replace the piston and piston rings as a set. NOTE: Before measuring the piston ring side clearance, eliminate any carbon deposits from the piston ring grooves and piston rings. 2. Install: Piston ring (into the cylind ...

Circuit diagram
2. Crankshaft position sensor 4. Main fuse 5. Main switch 6. Radiator fan motor fuse 8. Sidestand switch 9. Battery 17.Engine stop switch 19.Intake air pressure sensor 20.Intake air temperature sensor 21.Throttle position sensor 22.Coolant temperature sensor 23.Lean angle sensor 24.S ...