Yamaha YZF-R125 Service Manual: Checking the crankshaft
1. Measure:
- Crankshaft runout
Out of specification
Replace
the crankshaft, bearing or both.
NOTE:
Turn the crankshaft slowly.
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:
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 stator coil
1. Disconnect:
Stator coil coupler
(from the wire harness)
2. Check:
Stator coil resistance
Out of specification → Replace the
crankshaft
position sensor/stator assembly.
a. Connect the pocket tester ( ×
1) to the stator
coil coupler as shown.
b. Measure the sta ...
Checking the valves and valve guides
The following procedure applies to all of the
valves and valve guides.
1. Measure:
Valve-stem-to-valve-guide clearance
Out of specification Replace the
valve
guide.
Valve-stem-to-valve-guide clearance =
Valve guide inside diameter "a" -
Valve stem diameter "b"
2. Replace:
...