Yamaha YZF-R125 Service Manual: Checking the ignition timing

NOTE:

Prior to checking the ignition timing, check the wiring connections of the entire ignition system.

Make sure all connections are tight and free of corrosion.

1. Remove:

  • Rider seat
  • Left lower side cowling Refer to "GENERAL CHASSIS" on page 4-1.

2. Remove:

  • Timing mark accessing screw "1"

Checking the ignition timing


3. Lift the fuel tank. (Do not disconnect the fuel hose, fuel drain hose, and couplers.) Refer to "FUEL TANK" on page 7-1.

4. Connect:

  • Timing light "1"
  • Digital tachometer

Checking the ignition timing


5. Check:

  • Ignition timing

a. Start the engine, warm it up for several minutes, and then let it run at the specified engine idling speed.


b. Check that stationary pointer "a" in the generator cover is within the firing range "b" on the generator rotor.

Incorrect firing range → Check the ignition system.

Checking the ignition timing


NOTE:

The ignition timing is not adjustable.

6. Remove:

  • Digital tachometer
  • Timing light

7. Install:

  • Fuel tank Refer to "FUEL TANK" on page 7-1.

8. Install:

  • Timing mark accessing screw (along with the O-ring )

9. Install:

  • Left lower side cowling
  • Right side cover
  • Rider seat Refer to "GENERAL CHASSIS" on page 4-1.
    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 ...

    Measuring the compression pressure
    NOTE: Insufficient compression pressure will result in a loss of performance. 1. Measure: Valve clearance Out of specification →Adjust. Refer to "ADJUSTING THE VALVE CLEARANCE" on page ...

    Other materials:

    Circuit diagram
    4. Main fuse 5. Main switch 9. Battery 14.Neutral switch 25.ECU (engine control unit) 31.Fuel sender 34.Rear brake light switch 35.Front brake light switch 37.Tail/brake light 38.Rear right turn signal light 39.Rear left turn signal light 40.Front right turn signal light 41.Front lef ...

    Installing the steering head
    1. Lubricate: Upper bearing Lower bearing Bearing races 2. Install: Lower ring nut Rubber washer Upper ring nut Lock washer Refer to "CHECKING AND ADJUSTING THE STEERING HEAD" on page 3-22. 3. Install: Upper bracket Steering stem nut NOTE: Temporarily tighten t ...

    Checking the lean angle sensor
    1. Remove: Lean angle sensor 2. Check: Lean angle sensor output voltage Out of specification Replace. a. Connect the lean angle sensor to the wire harness. b. Connect the pocket tester (DC 20 V) to the lean angle sensor coupler as shown. Positive tester probe yellow/green "1" Neg ...

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