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

Yamaha YZF-R125 Service Manual / Periodic checks and adjustments / Engine / 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 ...

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