Yamaha YZF-R125 Service Manual: 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. Place a thermometer "4" in the water.

d. While stirring the water, observe the thermostat and thermometer's indicated temperature.

Checking the thermostat


A. Fully closed

B. Fully open

NOTE:

If the accuracy of the thermostat is in doubt, replace it. A faulty thermostat could cause serious overheating or overcooling.

2. Check:

  • Thermostat cover Cracks/damage Replace.

3. Check:

  • Radiator inlet hose Cracks/damage  Replace.

    Thermostat
    ...

    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 ...

    Other materials:

    Assembling the front brake caliper
    WARNING Before installation, all internal brake components should be cleaned and lubricated with clean or new brake fluid. Never use solvents on internal brake components as they will cause the brake caliper dust seals and piston seals to swell and distort. ...

    Sidestand
    The sidestand is located on the left side of the frame. Raise the sidestand or lower it with your foot while holding the vehicle upright. TIP The built-in sidestand switch is part of the ignition circuit cut-off system, which cuts the ignition in certain situations. WARNING The vehicl ...

    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 ...

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