Yamaha YZF-R125 Service Manual: Checking the rocker arms and rocker arm shafts

Yamaha YZF-R125 Service Manual / Engine / Camshaft / Checking the rocker arms and rocker arm shafts

The following procedure applies to all of the rocker arms and rocker arm shafts.

1. Check:

Rocker arm Damage/wear Replace.

2. Check:

Rocker arm shaft Blue discoloration/excessive wear/pitting/ scratches Replace or
check the lubrication system.

3. Measure:

Rocker arm inside diameter "a" Out of specification Replace.

Checking the rocker arms and rocker arm shafts

4. Measure:

Rocker arm shaft outside diameter "a" Out of specification Replace.

Checking the rocker arms and rocker arm shafts

5. Calculate:

Rocker-arm-to-rocker-arm-shaft clearance

NOTE:

Calculate the clearance by subtracting the rocker arm shaft outside diameter from the rocker arm inside diameter.

Out of specification Replace the
defective part(s).

Checking the camshaft

1. Check: Camshaft lobes Blue discoloration/pitting/scratches Replace the camshaft. 2. Measure: Camshaft lobe dimensions "a" and "b" Out of specification Replace the cams ...

Installing the camshaft and rocker arms

1. Lubricate: Rocker arms Rocker arm shafts 2. Lubricate: Camshaft 3. Install: Camshaft "1" NOTE: Make sure that the camshaft projections "a" and hole "b" are positioned as s ...

Other materials:

Removing the front fork legs
The following procedure applies to both of the front fork legs. 1. Stand the vehicle on a level surface. WARNINGSecurely support the vehicle so that there is no danger of it falling over. 2. Loosen: Handlebar pinch bolt "1" Handlebar bolt "2" Upper bracket ...

Removing the rear wheel (disc)
1. Stand the vehicle on a level surface. WARNINGSecurely support the vehicle so that there is no danger of it falling over. 2. Elevate: Rear wheel NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated. 3. Remove: Rear brake caliper NOTE: ...

Installing the front brake master cylinder
1. Install: Brake master cylinder "1" Brake master cylinder holder "2" NOTE: Install the brake master cylinder holder with the arrow mark "a" pointing forward. Align the end of the brake master cylinder holder with the punch mark "b" on the handlebar. First, tighten the front bo ...