Yamaha YZF-R125 Service Manual: 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 into the cylinder.

4. Check:

Spark plug type Incorrect →Change.


5. Check:

  • Electrode "1" Damage/wear→ Replace the spark plug.
  • Insulator "2" Abnormal color→ Replace the spark plug.

    Normal color is medium-to-light tan.

6. Clean:

  • Spark plug (with a spark plug cleaner or wire brush)

7. Measure:

  • Spark plug gap "a" (with a wire thickness gauge) Out of specification → Regap.

Checking the spark plug


8. Install:

  • Spark plug

NOTE:

Before installing the spark plug, clean the spark plug and gasket surface.

9. Connect:

  • Spark plug cap

10.Install:

  • Right side cover Refer to "GENERAL CHASSIS" on page 4-1.
    Adjusting the throttle cable free play
    NOTE: Prior to adjusting the throttle cable free play, the engine idling speed should be adjusted. 1. Check: Throttle cable free play "a" Out of specification →Adjust. 2. Remov ...

    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 L ...

    Other materials:

    Checking the coolant temperature sensor
    1. Remove: Coolant temperature sensor WARNING Handle the coolant temperature sensor with special care. Never subject the coolant temperature sensor to strong shocks. If the coolant temperature sensor is dropped, replace it. 2. Check: Coolant temper ...

    Installing the primary drive gear and balancer gears
    1. Install: Balancer driven gear "1" Lock washer Balancer drive gear "2" Primary drive gear Washer "3" Balancer driven gear nut Primary drive gear nut NOTE: Align the punch mark "a" in the balancer drive gear "2" with the punch mark "b" in the balancer driven gear "1". ...

    Intake air pressure sensor
    1. Check: Intake air pressure sensor output voltage Out of specification Replace the throttle body. a. Connect the pocket tester (DC 20 V) to the throttle body sensor assembly coupler as shown. Positive tester probe pink/white "1" Negative tester probe gray/black "2" ...

    2021 Copyright www.yam-r125.net |