Yamaha YZF-R125 Service Manual: Assembling the crankcase
1. Thoroughly clean all the gasket mating surfaces and crankcase mating surfaces.
2. Apply:
- Sealant
(onto the crankcase mating surfaces)
NOTE:
Do not allow any sealant to come into contact with the oil gallery.
3. Install:
- Right crankcase
NOTE:
Turn the shift drum segment "1" to the position shown in the illustration. In this position, the shift drum segment teeth will not contact the crankcase during crankcase installation.
4. Install:
- Crankcase bolts
NOTE:
Tighten each bolt 1/4 of a turn at a time, in stages and in the proper sequence as shown.
- M6 × 70 mm : "7-9", "11"
- M6 × 55 mm : "14", "15"
- M6 × 45 mm : "1-5", "10"
A. Left crankcase
B. Right crankcase
Installing the bearing retainer
1. Install:
Bearing retainer "1"
NOTE:
Install the bearing retainer "1" with its "OUT"
mark "a" facing outward.
Apply locking agent (LOCTITE) to the
threads of the bearing retainer bo ...
Crankshaft
...
Other materials:
Checking the timing chain and timing chain guide
1. Check:
Timing chain
Damage/stiffness Replace the
timing
chain and camshaft sprocket as a set.
2. Check:
Timing chain guide (intake side)
Damage/wear Replace.
Checking the oil strainer
1. Check:
Oil strainer
Damage Replace.
Contaminants Clean with solvent.
...
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:
...
Checking the starter motor
1. Check:
Commutator
Dirt Clean with 600 grit
sandpaper.
2. Measure:
Commutator diameter "a"
Out of specification Replace
the starter
motor.
3. Measure:
Mica undercut "a"
Out of specification Scrape
the mica to the
proper measurement with a hacksaw blade
...