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:
Checking the spark plug cap
1. Check:
Spark plug cap resistance
Out of specification Replace.
a. Remove the spark plug cap from the spark
plug lead.
b. Connect the pocket tester ( × 1k)
to the
spark plug cap as shown.
c. Measure the spark plug cap resistance. ...
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".
...
Safe Riding
Perform the pre-operation checks each
time you use the vehicle to make sure it
is in safe operating condition. Failure to
inspect or maintain the vehicle properly
increases the possibility of an accident
or equipment damage. See page 4-1
for a list of pre-operation checks.
This motor ...