Suzuki GN125F Service Manual page 43

Valve seat angle
Valve width
Intake side
o
45 N-122
o
30
N-126
o
N-111
60
09916-21110: Valve reamer set
Check the contact surface institute.
If found any defective, service the valve seat.
o
Using the 45 reamer, descale and cleanup the seat with
one or two turns.
Check the contact position.
is too high, finish it with 30 reamer to reduce the height.
If the contact face of valve is too low finish it with 60
reamer to increase the height.
Finish the valve seat surface again to standard range with
o
45 reamer .
NOTE:
The valve seat position will affect the contact surface
of valve, this is very important to the good sealing.
INTAKE
EXHAUST
O O
30 , 45
0.9-1.1mm
Exhaust side
o
N-122
45
o
15 N-121
If the contact face of the valve
°
ENGINE
O O
15 , 45
°
3-12
EXHAUST
valve seat
Damaged surface Uneven contact surface
Contact surface is too high
Contact surface is too low
o
45
o
30
o
60