Yamaha YZF-R125 Service Manual: Checking the crankshaft position sensor

Yamaha YZF-R125 Service Manual / Electrical system / Electrical components / 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 coupler as shown.


  • Positive tester probe
    red "1"
  • Negative tester probe
    white "2"

b. Measure the crankshaft position sensor resistance.

    Checking the ignition spark gap
    1. Check: Ignition spark gap Out of specification Perform the ignition system troubleshooting, starting with step 5. Refer to "TROUBLESHOOTING" on page 8-3. NOTE: If the ignition spark gap ...

    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 ...

    Other materials:

    Checking the front and rear brake pads
    The front and rear brake pads must be checked for wear at the intervals specified in the periodic maintenance and lubrication chart. Front brake pads Remove the front brake caliper by removing the bolts. Bolt Brake caliper Lining thickness Check each front br ...

    Checking the clutch springs
    The following procedure applies to all of the clutch springs. 1. Check: Clutch spring Damage Replace the clutch springs as a set. 2. Measure: Clutch spring free length "a" Out of specification Replace the clutch springs as a set. ...

    Installing the front wheel (disc)
    1. Install: Front brake disc NOTE: Be sure to install the front brake disc with the arrow mark "a" on the disc facing out. Tighten the brake disc bolts in stages and in a crisscross pattern. 2. Check: Front brake disc Refer to "CHECKING THE FRONT BRAKE DISC" on page 4 ...

    2026 Copyright www.yam-r125.net |