Yamaha YZF-R125 Service Manual: Adjusting the engine idling speed

NOTE:

Prior to adjusting the engine idling speed, the air filter element should be clean, and the engine should have adequate compression.

1. Start the engine and let it warm up for several minutes.

2. Remove:

  • Rider seat Refer to "GENERAL CHASSIS" on page 4-1.

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. Install:

  • Digital tachometer (onto the spark plug lead)

5. Check:

Engine idling speed Out of specification → Adjust.


6. Remove:

  • Right side panel Refer to "GENERAL CHASSIS" on page 4-1.

7. Adjust:

  • Engine idling speed

a. Turn the pilot screw "1" in direction "a" or "b" until the specified engine idling speed is obtained.

Adjusting the engine idling speed



8. Remove:

  • Digital tachometer

9. Install:

  • Fuel tank Refer to "FUEL TANK" on page 7-1.
  • Right side panel
  • Rider seat Refer to "GENERAL CHASSIS" on page 4-1.

10.Adjust:

  • Throttle cable free play Refer to "ADJUSTING THE THROTTLE CABLE FREE PLAY" on page 3-6.

    Adjusting the exhaust gas volume
    NOTE: Be sure to set the CO density level to standard, and then adjust the exhaust gas volume. 1. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 2. Set the main switch to "OFF" ...

    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 ...

    Other materials:

    Assembling the front brake caliper
    WARNING Before installation, all internal brake components should be cleaned and lubricated with clean or new brake fluid. Never use solvents on internal brake components as they will cause the brake caliper dust seals and piston seals to swell and distort. ...

    Checking the throttle body joint and air filter case joint
    1. Remove: Right lower side cowling Left lower side cowling Refer to "GENERAL CHASSIS" on page 4-1. 2. Check: Throttle body joint "1" Air filter case joint "2" Cracks/damage Replace. 3. Install: Right lower side cowling Left lower side cowling Refer to "GENERAL CHAS ...

    Aftermarket Parts, Accessories, and Modifications
    While you may find aftermarket products similar in design and quality to genuine Yamaha accessories, recognize that some aftermarket accessories or modifications are not suitable because of potential safety hazards to you or others. Installing aftermarket products or having other modif ...

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