Yamaha YZF-R125 Service Manual: Checking the camshaft

Yamaha YZF-R125 Service Manual / Engine / Camshaft / 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 camshaft.

Checking the camshaft


3. Check:

Camshaft oil passage Obstruction Blow out with
compressed air.

    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 wea ...

    Other materials:

    Checking the crankshaft position sensor
    1. Disconnect: Crankshaft position sensor coupler (from the wire harness) 2. Check: Crankshaft position sensor resistance Out of specification  Replace the crankshaft position sensor/stator assembly. a. Connect the pocket tester ( × 100) to the crankshaft position sensor c ...

    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" ...

    Troubleshooting
    Although Yamaha motorcycles receive a thorough inspection before shipment from the factory, trouble may occur during operation. Any problem in the fuel, compression, or ignition systems, for example, can cause poor starting and loss of power. The following troubleshooting charts repre ...

    2026 Copyright www.yam-r125.net |