Yamaha YZF-R125 Service Manual: Checking the coolant level

1. Stand the vehicle on a level surface.

NOTE:

  • Place the vehicle on a suitable stand.
  • Make sure the vehicle is upright.

2. Check:

Coolant level The coolant level should be between the maximum level mark "a" and minimum level mark "b".

Below the minimum level mark →  Add the recommended coolant to the proper level.

NOTE:

To access the coolant reservoir cap "1", remove the right side cover. Refer to "GENERAL CHASSIS" on page 4-1.

Checking the coolant level


CAUTION:
  • Adding water instead of coolant lowers the antifreeze content of the coolant. If water is used instead of coolant, check and, if necessary, correct the antifreeze concentration of the coolant.
  • Use only distilled water. However, if distilled water is not available, soft water may be used.

3. Start the engine, warm it up for several minutes, and then turn it off.

4. Check:

  • Coolant level

NOTE:

Before checking the coolant level, wait a few minutes until it settles.

    Checking the exhaust system
    1. Check: Exhaust assembly "1" Cracks/damage → Replace. Exhaust pipe gasket "2" Exhaust gas leaks → Replace. 2. Check: Tightening torques of the exhaust pipe nuts "3" an ...

    Checking the cooling system
    1. Remove: Side covers Upper side cowlings Refer to "GENERAL CHASSIS" on page 4-1. 2. Check: Radiator "1" Radiator inlet hose "2" Radiator outlet hose "3" Coolant reservoir hose ...

    Other materials:

    Checking the cylinder and piston
    1. Check: Piston wall Cylinder wall Vertical scratches Replace the cylinder, and replace the piston and piston rings as a set. 2. Measure: Piston-to-cylinder clearance a. Measure cylinder bore "C" with the cylinder bore gauge. NOTE: Measure cylinder bore "C" by takin ...

    Starting failures
    Engine 1. Cylinder and cylinder head - Loose spark plug - Loose cylinder head or cylinder - Damaged cylinder head gasket - Damaged cylinder gasket - Worn or damaged cylinder - Incorrect valve clearance - Improperly sealed valve - Incorrect valve-to-valve-seat contact - Incorrect valve timi ...

    Checking the rear brake disc
    1. Remove: Rear wheel Refer to "REAR WHEEL" on page 4-12. 2. Check: Brake disc Damage/galling → Replace. 3. Measure: Brake disc deflection Out of specification → Correct the brake disc deflection or replace the brake disc. Refer to "CHECKING THE FRONT BRAKE DIS ...

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