Yamaha YZ250F(S) Owner's Service Manual page 332

VALVES AND VALVE SPRINGS
ASSEMBLY AND INSTALLATION
Valve and valve spring
1. Apply:
2. Install:
NOTE:
Make sure that each valve is installed in its
G
original place, also referring to the painted
color as follows.
Install the valve springs with the larger pitch
G
c facing upward.
d Smaller pitch
3. Install:
NOTE:
While compressing the valve spring with a
valve spring compressor 1 install the valve
cotters.
4. To secure the valve cotters onto the
CAUTION:
Hitting the valve tip with excessive force
could damage the valve.
4 - 40
Molybdenum disulfide oil
G
Onto the valve stem and valve stem
seal.
Valve 1
G
Valve spring seat 2
G
Valve stem seal 3
G
Valve spring 4
G
Valve spring retainer 5
G
To cylinder head.
Intake (middle) a: yellow
Intake (right/left) b: white
Exhaust: no paint
Valve cotter
G
Valve spring compressor:
YM-4019/90890-04019
valve stem, lightly tap the valve tip with a
piece of wood.
ENG