Yamaha YZF-R125 Service Manual: Checking the crankshaft

Yamaha YZF-R125 Service Manual / Engine / Crankshaft / Checking the crankshaft

1. Measure:

Crankshaft runout Out of specification Replace
the crankshaft, bearing or both.

NOTE:

Turn the crankshaft slowly.

Checking the crankshaft

2. Measure:

Big end side clearance Out of specification Replace
the crankshaft.

3. Measure:

Crankshaft width Out of specification
Replace the crankshaft.

3. Measure:

Crankshaft width Out of specification Replace the crankshaft.

4. Check:

Crankshaft sprocket Damage/wear Replace the
crankshaft.
Bearing Cracks/damage/wear Replace the
crankshaft.

5. Check:

Crankshaft journal Scratches/wear Replace the
crankshaft.
Crankshaft journal oil passage Obstruction Blow out with
compressed air.

Removing the crankshaft

1. Remove: Crankshaft "1" NOTE: Remove the crankshaft with the crankcase separating tool "2". Make sure the crankcase separating tool is centered over the crankshaft. CAUTIO ...

Installing the crankshaft

1. Install: Crankshaft "1" NOTE: Install the crankshaft with the crankshaft installer pot "2", crankshaft installer bolt "3", adapter (M12) "4" and spacer (crankshaft installer) "5". ...

Other materials:

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 vehicle is used in dusty areas. This vehicle has a drive chain with small rubber O-rings between eac ...

Outline of the fi system
The main function of a fuel supply system is to provide fuel to the combustion chamber at the optimum air-fuel ratio in accordance with the engine operating conditions and the atmospheric temperature. In the conventional carburetor system, the air-fuel ratio of the mixture that is supplied t ...

Checking the tires
The following procedure applies to both of the tires. 1. Check: Tire pressure Out of specification Regulate. WARNING The tire pressure should only be checked and regulated when the tire temperature equals the ambient air temperature. The tire pressure must be adjuste ...