Yamaha YZF-R125 Service Manual: Installing the primary drive gear and balancer gears

Yamaha YZF-R125 Service Manual / Engine / Balancer gear / Installing the primary drive gear and balancer gears

1. Install:

Balancer driven gear "1"
Lock washer

Balancer drive gear "2"
Primary drive gear
Washer "3"
Balancer driven gear nut
Primary drive gear nut

NOTE:

Align the punch mark "a" in the balancer drive gear "2" with the punch mark "b" in the balancer driven gear "1".
Be sure to install the washer so that its sharp edge "c" is facing the primary drive gear.

Installing the primary drive gear and balancer gears

2. Tighten:

Balancer driven gear nut "1"
Primary drive gear nut "2"

NOTE:

Place the aluminum plate "a" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the balancer driven gear nut.
Place the aluminum plate "b" between the balancer drive gear "3" and the balancer driven gear "4", and then tighten the primary drive gear nut.

Installing the primary drive gear and balancer gears

3. Bend the lock washer tab along a flat side of the nut.

Checking the balancer gears and primary drive gear

1. Check: Balancer drive gear Balancer driven gear Cracks/damage/wear Replace. 2. Check: Primary drive gear Refer to "CHECKING THE PRIMARY DRIVE GEAR" on page 5-43. ...

Crankcase

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Other materials:

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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 " ...

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