Yamaha YZF-R125 Service Manual: Checking the rocker arms and rocker arm shafts

Yamaha YZF-R125 Service Manual / Engine / Camshaft / Checking the rocker arms and rocker arm shafts

The following procedure applies to all of the rocker arms and rocker arm shafts.

1. Check:

  • Rocker arm Damage/wear Replace.

2. Check:

  • Rocker arm shaft Blue discoloration/excessive wear/pitting/ scratches  Replace or
    check the lubrication system.

3. Measure:

  • Rocker arm inside diameter "a" Out of specification Replace.

Checking the rocker arms and rocker arm shafts


4. Measure:

  • Rocker arm shaft outside diameter "a" Out of specification Replace.

Checking the rocker arms and rocker arm shafts


5. Calculate:

  • Rocker-arm-to-rocker-arm-shaft clearance

NOTE:

Calculate the clearance by subtracting the rocker arm shaft outside diameter from the rocker arm inside diameter.

Out of specification Replace the
defective part(s).


    Checking the camshaft
    1. Check: Camshaft lobes Blue discoloration/pitting/scratches  Replace the camshaft. 2. Measure: Camshaft lobe dimensions "a" and "b" Out of specification Replace the cams ...

    Installing the camshaft and rocker arms
    1. Lubricate: Rocker arms Rocker arm shafts 2. Lubricate: Camshaft 3. Install: Camshaft "1" NOTE: Make sure that the camshaft projections "a" and hole "b" are positioned as s ...

    Other materials:

    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 ...

    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. ...

    Specifications
    Dimensions: Overall length: 2015 mm (79.3 in) Overall width: 660 mm (26.0 in) Overall height: 1065 mm (41.9 in) Seat height: 818 mm (32.2 in) Wheelbase: 1355 mm (53.3 in) Ground clearance: 155 mm (6.10 in) Minimum turning radius: 3100 mm (122.0 in) Weight: With oil and fuel: 138.0 k ...

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