Yamaha YZF-R125 Service Manual: Adjusting the drive chain slack

NOTE:

The drive chain slack must be checked at the tightest point on the chain.

CAUTION:

A drive chain that is too tight will overload the engine and other vital parts, and one that is too loose can skip and damage the swingarm or cause an accident. Therefore, keep the drive chain slack within the specified limits.

1. Stand the vehicle on a level surface.

WARNING

Securely support the vehicle so that there is no danger of it falling over.

NOTE:

Both wheels should be on the ground without a rider on the vehicle.

2. Turn the rear wheel several times and find the tightest position on the drive chain.

3. Check:

  • Drive chain slack "a" Out of specification Adjust.

Adjusting the drive chain slack


NOTE:

Measure the drive chain slack halfway between the drive axle and the rear wheel axle.

4. Adjust:

  • Drive chain slack

a. Loosen the wheel axle nut "1".

b. Loosen both locknuts "2".

c. Turn both adjusting bolts "3" in direction "a" or "b" until the specified drive chain slack is obtained.


Adjusting the drive chain slack


NOTE:

  • To maintain the proper wheel alignment, adjust both sides evenly
  • Push the rear wheel forward to make sure there is no clearance between the drive chain pullers and the ends of the adjusting bolts.

d. Tighten the wheel axle nut to specification.


e. Tighten the locknuts to specification.


    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. brak ...

    Lubricating the drive chain
    The drive chain consists of many interacting parts. If the drive chain is not maintained properly, it will wear out quickly. Therefore, the drive chain should be serviced, especially when the vehi ...

    Other materials:

    Unstable handling
    Handlebars - Bent or improperly installed right handlebar - Bent or improperly installed left handlebar 1. Steering head components - Improperly installed upper bracket - Improperly installed lower bracket (improperly tightened ring nut) - Bent steering stem - Damaged ball bearing or bearing ...

    Checking the fuel line
    1. Remove: Left side panel Refer to "GENERAL CHASSIS" on page 4-1. 2. Lift the fuel tank. (Do not disconnect the fuel hose, drain hose 3. Check: Fuel hose "1" Cracks/damage → Replace. Loose connection Connect properly. 4. Install: Fuel tank Refer to "FUEL TANK" on pa ...

    Removing the front brake caliper
    NOTE: Before disassembling the brake caliper, drain the brake fluid from the entire brake system. 1. Remove: Brake hose union bolt "1" Copper washers "2" Brake hose "3" NOTE: Put the end of the brake hose into a container and pump out the brake fluid carefully. ...

    2026 Copyright www.yam-r125.net |