Yamaha YZF-R125 Service Manual: Checking the valve springs
The following procedure applies to all of the valve springs.
1. Measure:
- Valve spring free length "a"
Out of specification Replace the valve
spring.
2. Measure:
- Compressed valve spring force "a"
Out of specification Replace the valve
spring.
b. Installed length
3. Measure:
- Valve spring tilt "a"
Out of specification
Replace the
valve spring.
Checking the valve seats
The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
Carbon deposits
(from the valve face and valve seat)
2. Check:
Valve seat
Pitting/wear Replace the ...
Installing the valves
The following procedure applies to all of the
valves and related components.
1. Deburr:
Valve stem end
(with an oil stone)
2. Lubricate:
Valve stem "1"
Valve stem seal "2"
(with ...
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.
...
Adjusting the clutch lever free play
Adjusting the clutch lever free play
Clutch lever free play adjusting bolt
Clutch lever free play
The clutch lever free play should measure
10.0-15.0 mm (0.39-0.59 in) as
shown. Periodically check the clutch lever
free play and, if necessary, adjust it
as follows.
Slide the ...
Checking the camshaft sprocket and timing chain guide
1. Check:
Camshaft sprocket
More than 1/4 tooth wear "a" Replace
the
camshaft sprocket, timing chain and crankshaft
as a set.
a. 1/4 tooth
b. Correct
1. Timing chain roller
2. Camshaft sprocket
2. Check:
Timing chain guide (exhaust side)
Damage/wear Replace.
...