Yamaha YZF-R125 Service Manual: 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 the recommended lubricant)
3. Install:
- Lower spring seat "1"
- Valve stem seal "2"
- Valve "3"
- Valve spring "4"
- Upper spring seat "5" (into the cylinder head)
NOTE:
- Make sure each valve is installed in its original place.
- Install the valve springs with the larger pitch "a" facing up.
b. Smaller pitch
4. Install:
- Valve cotters "1"
NOTE:
Install the valve cotters by compressing the
valve spring with the valve spring compressor
and the valve spring compressor attachment "2".
5. To secure the valve cotters onto the valve stem, lightly tap the valve tip with a soft-face hammer.
| CAUTION: Hitting the valve tip with excessive force could damage the valve. |
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 ...
Other materials:
Starting circuit cut-off system operation
If the engine stop switch is set to "
" and the main switch is set to
"ON" (both switches are closed), the
starter motor can only operate if at least one of the following conditions is
met:
The transmission is in neutral (the neutral switch is closed).
The clutch lever is pulled to the ...
Rider seat
To remove the rider seat
Insert the key into the seat lock,
and then turn it clockwise.
Seat lock
Open.
Pull the rider seat off.
To install the rider seat
1. Insert the projection on the front of
the rider seat into the seat holder
as shown.
Projection
...
Checking the coolant temperature sensor
1. Remove:
Coolant temperature sensor
WARNING
Handle the coolant temperature sensor
with special care.
Never subject the coolant temperature sensor
to strong shocks. If the coolant temperature
sensor is dropped, replace it.
2. Check:
Coolant temper ...