Yamaha YZF-R125 Service Manual: Installing the thermostat

1. Install:

  • Thermostat

NOTE:

Install the thermostat with its breather hole "a" facing up.


2. Install:

  • Copper washer

  • Coolant temperature sensor

CAUTION:

Use extreme care when handling the coolant temperature sensor. Replace any part that was dropped or subjected to a strong impact.

3. Fill:

  • Cooling system (with the specified amount of the recommended coolant) Refer to "CHANGING THE COOLANT" on page 3-15.

4. Check:

  • Cooling system Leaks Repair or replace any
    faulty part.

5. Measure:

  • Radiator cap opening pressure Below the specified pressure 
    Replace the radiator cap.

    Refer to "CHECKING THE RADIATOR" on page 6-3.

    Checking the thermostat
    1. Check: Thermostat Does not open at 80.5-83.5 C (176.9-182.3 F)  Replace. a. Suspend the thermostat "1" in a container "2" filled with water. b. Slowly heat the water "3". c. ...

    Water pump
    ...

    Other materials:

    Checking the condition of the bulbs
    The following procedure applies to all of the bulbs. 1. Remove: Bulb WARNINGSince the headlight bulbs get extremely hot, keep flammable products and your hands away from them until they have cooled down. CAUTION: Be sure to hold the socket firmly when re ...

    Adjusting the throttle cable free play
    Throttle cable free play The throttle cable free play should measure 3.0-5.0 mm (0.12-0.20 in) at the throttle grip. Periodically check the throttle cable free play and, if necessary, adjust it as follows. TIP The engine idling speed must be correctly adjusted before checkin ...

    Battery
    A poorly maintained battery will corrode and discharge quickly. The electrolyte level, battery lead connections and breather hose routing should be checked before each ride and at the intervals specified in the periodic maintenance and lubrication chart. WARNING Electrolyte is pois ...

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