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:
Sidestand
The sidestand is located on the left side
of the frame. Raise the sidestand or
lower it with your foot while holding the
vehicle upright.
TIP
The built-in sidestand switch is part of
the ignition circuit cut-off system, which
cuts the ignition in certain situations.
WARNING
The vehicl ...
Checking the drive sprocket
1. Check:
Drive sprocket
More than 1/4 tooth "a" wear
Replace the
drive chain sprockets as a set.
Bent teeth Replace the drive
chain sprockets
as a set.
b. Correct
1. Drive chain roller
2. Drive chain sprocket
Checking the rear wheel sprocket
Refer to "CHECKING AND R ...
Circuit diagram
4. Main fuse
5. Main switch
9. Battery
14.Neutral switch
25.ECU (engine control unit)
31.Fuel sender
34.Rear brake light switch
35.Front brake light switch
37.Tail/brake light
38.Rear right turn signal light
39.Rear left turn signal light
40.Front right turn signal light
41.Front lef ...