Yamaha YZF-R125 Service Manual: Checking the speed sensor

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"

Checking the speed sensor


b. Set the main switch to "ON".

c. Elevate the front wheel and slowly rotate it.

d. Measure the voltage of gray and gray/black.

With each full rotation of the front wheel, the voltage reading should cycle from 0 V to 5.0 V to 0 V to 5.0 V.

    Checking the fuel sender
    1. Drain the fuel from the fuel tank. 2. Check: Fuel sender resistance Out of specification → Replace the fuel sender. a. Connect the pocket tester ( × 10) to the fuel sender c ...

    Checking the radiator fan motor
    1. Check: Radiator fan motor Faulty/rough movement → Replace. a. Disconnect the radiator fan motor coupler from the wire harness. b. Connect the battery (DC 12 V) as shown. Posi ...

    Other materials:

    Checking the front fork
    The condition and operation of the front fork must be checked as follows at the intervals specified in the periodic maintenance and lubrication chart. To check the condition Check the inner tubes for scratches, damage and excessive oil leakage. To check the operation Place the vehicle ...

    Disassembling the water pump
    1. Remove: Water pump seal "1" NOTE: Remove the water pump seal from the inside of the water pump housing "2". 2. Remove: Bearing "1" NOTE: Remove the bearing from the outside of the water pump housing "2". ...

    Removing the swingarm
    1. Stand the vehicle on a level surface. WARNINGSecurely support the vehicle so that there is no danger of it falling over. NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated. 2. Measure: Swingarm side play Swingarm vertical movement a. Me ...

    2023 Copyright www.yam-r125.net |