Yamaha YZF-R125 Service Manual: 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 "4"

Water pump breather hose "5" Cracks/damage → Replace.

Refer to "RADIATOR" on page 6-1.

Checking the cooling system


3. Install:

  • Upper side cowlings
  • Side covers Refer to "GENERAL CHASSIS" on page 4-1.
    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 max ...

    Changing the coolant
    1. Remove: Lower side cowlings Refer to "GENERAL CHASSIS" on page 4-1. 2. Remove: Radiator cap "1" WARNINGA hot radiator is under pressure. Therefore, do not remove t ...

    Other materials:

    Bleeding the hydraulic brake system
    WARNINGBleed the hydraulic brake system whenever: the system is disassembled. a brake hose is loosened, disconnected or replaced. the brake fluid level is very low. brake operation is faulty. NOTE: Be careful not to spill any brake fluid or allow th ...

    Removing the primary drive gear and balancer gears
    1. Loosen: Primary drive gear nut "1" NOTE: Place the aluminum plate "a" between the balancer drive gear "2" and the balancer driven gear "3", and then loosen the primary drive gear nut. 2. Straighten the lock washer tab. 3. Loosen: Balancer driven gear nut "1" NOTE: Place ...

    Checking the transmission
    1. Measure: Main axle runout (with a centering device and dial gauge "1") Out of specification Replace the main axle. 2. Measure: Drive axle runout (with a centering device and dial gauge "1") Out of specification Replace the drive axle. 3. Check: Transmiss ...

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