Yamaha YZF-R125 Service Manual: Checking the cylinder head breather hose

Yamaha YZF-R125 Service Manual / Periodic checks and adjustments / Engine / Checking the cylinder head breather hose

1. Remove:

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

2. Check:

  • Cylinder head breather hose "1" Cracks/damage → Replace.

    Loose connection → Connect properly.

CAUTION:

Make sure the cylinder head breather hose is routed correctly.

Checking the cylinder head breather hose


3. Install:

  • Left side panel Refer to "GENERAL CHASSIS" on page 4-1.
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    1. Check: Exhaust assembly "1" Cracks/damage → Replace. Exhaust pipe gasket "2" Exhaust gas leaks → Replace. 2. Check: Tightening torques of the exhaust pipe nuts "3" an ...

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    1. Check: Speed sensor output voltage Out of specification → Replace. a. Connect the pocket tester (DC 20 V) to the speed sensor coupler (wire harness end) as shown. Positive tester probe gray "1" Negative tester probe gray/black "2" b. Set the main switch to "ON". c. ...

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