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:

Tachometer
Tachometer Tachometer Tachometer red zone The electric tachometer allows the rider to monitor the engine speed and keep it within the ideal power range. When the key is turned to "ON", the tachometer needle will sweep once across the r/min range and then return to zero r/min ...

Checking the condition of the bulbs
The following procedure applies to all of the bulbs. 1. Remove: Bulb WARNINGSince the headlight bulbs get extremely hot, keep flammable products and your hands away from them until they have cooled down. CAUTION: Be sure to hold the socket firmly when re ...

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 " ...