Yamaha YZF-R125 Service Manual: Checking the drive sprocket

Yamaha YZF-R125 Service Manual / Chassis / Chain drive / Checking the drive sprocket

1. Check:

  • Drive sprocket More than 1/4 tooth "a" wear
    Replace the drive chain sprockets as a set.

    Bent teeth Replace the drive
    chain sprockets as a set.

Checking the drive sprocket


b. Correct

1. Drive chain roller

2. Drive chain sprocket

Checking the rear wheel sprocket

Refer to "CHECKING AND REPLACING THE REAR WHEEL SPROCKET" on page 4-15.

Checking the rear wheel drive hub

Refer to "CHECKING THE REAR WHEEL DRIVE HUB" on page 4-15.

    Checking the drive chain
    1. Measure: 15-link section "a" of the drive chain Out of specification Replace the drive chain. a. Measure the length "a" between the inner sides of the pins and the length "b" between t ...

    Installing the drive chain
    1. Lubricate: Drive chain Master link 2. Install: Drive sprocket Drive sprocket retainer bolts 3. Install: Master link O-rings Master link plate Master link clip "1" ...

    Other materials:

    Checking the decompression system
    1. Check: Decompression system a. Check the decompression system with the camshaft sprocket and the decompression cam installed to the camshaft. b. Check that the decompression lever "1" moves smoothly. c. Without operating the decompression lever, check that the decompression cam " ...

    Installing the drive chain
    1. Lubricate: Drive chain Master link 2. Install: Drive sprocket Drive sprocket retainer bolts 3. Install: Master link O-rings Master link plate Master link clip "1" CAUTION: The closed end of the master link clip must face in the direction of drive ch ...

    Checking the front wheel
    1. Check: Front wheel axle Roll the wheel axle on a flat surface. Bends → Replace. WARNINGDo not attempt to straighten a bent wheel axle. 2. Check: Tire Front wheel Damage/wear → Replace. Refer to "CHECKING THE TIRES" on page 3-23 and "CHECKING TH ...

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