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:
Removing the rear brake master cylinder
NOTE:
Before removing the rear brake master cylinder,
drain the brake fluid from the entire brake system.
1. Disconnect:
Rear brake light switch coupler
2. Loosen:
Rear brake light switch "1"
3. Remove:
Rear brake master cylinder bolts
Rear brake master cylinder
4. Remove:
...
Fuel tank cap
Fuel tank cap
Fuel tank cap lock cover
Unlock.
To remove the fuel tank cap
Open the fuel tank cap lock cover.
Insert the key into the lock and turn
it 1/4 turn counterclockwise. The
lock will be released and the fuel
tank cap can be removed.
To install the fuel tank ca ...
Checking the starter motor operation
1. Check:
Starter motor operation
Does not operate → Perform the electric
starting system troubleshooting, starting with
step 4.
Refer to "TROUBLESHOOTING" on page
8-9.
a. Connect the positive battery terminal "1" and
starter motor lead "2" with a jumper lead "3".
W ...