Yamaha YZF-R125 Service Manual: Troubleshooting

If the fuel pump fails to operate.

NOTE:

  • Before troubleshooting, remove the following part(s):

1. Rider seat

2. Fuel tank

Troubleshooting


    Circuit diagram
    4. Main fuse 5. Main switch 9. Battery 17.Engine stop switch 25.ECU (engine control unit) 30.Fuel pump 64.Ignition fuse ...

    Electrical components
    1. Main switch 2. Clutch switch 3. Front brake light switch 4. Ignition coil 5. Throttle body sensor assembly (intake air pressure sensor, intake air temperature sensor, throttle position se ...

    Other materials:

    Checking the valves and valve guides
    The following procedure applies to all of the valves and valve guides. 1. Measure: Valve-stem-to-valve-guide clearance Out of specification Replace the valve guide. Valve-stem-to-valve-guide clearance = Valve guide inside diameter "a" - Valve stem diameter "b" 2. Replace: ...

    Checking the clutch housing
    1. Check: Clutch housing dogs "1" Damage/pitting/wear  Deburr the clutch housing dogs or replace the clutch housing. NOTE: Pitting on the clutch housing dogs will cause erratic clutch operation. 2. Check: Bearing Damage/wear Replace the bearing and clutch housin ...

    Checking the spark plug
    1. Remove: Right side cover Refer to "GENERAL CHASSIS" on page 4-1. 2. Disconnect: Spark plug cap 3. Remove: Spark plug CAUTION:Before removing the spark plug, blow away any dirt accumulated in the spark plug well with compressed air to prevent it from falling ...

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