Honda CBF600SA Service Manual page 277

Manuals by Motomatrix / www.motomatrix.co.uk / The Solution For Lost Motorcycle Coded Keys.
VALVE SEAT INSPECTION/REFACING
Clean the intake and exhaust valves thoroughly to
remove carbon deposits.
Apply a light coating of Prussian Blue to the valve
seats.
Tap the valves and seats using a rubber hose or
other hand-lapping tool.
Remove the valve and inspect the valve seat face.
The valve seat contact should be within the speci-
fied width and even all around the circumference.
STANDARD:
IN/EX: 0.90 – 1.10 mm (0.035 – 0.043 in)
SERVICE LIMIT:
IN/EX: 1.5 mm (0.06 in)
If the seat width is not within specification, reface
the valve seat (page 8-20).
Inspect the valve seat face for:
• Uneven seat width:
– Replace the valve and reface the valve seat.
• Damaged face:
– Replace the valve and reface the valve seat.
• Contact area (too high or too low)
The valves cannot
– Reface the valve seat.
be ground. If a
valve face is burned
or badly worn or if it
contacts the seat
unevenly, replace
the valve.
email: info@motomatrix.co.uk
CYLINDER HEAD/VALVES
HAND-LAPPING TOOL
UNEVEN SEAT WIDTH
DAMAGED FACE
TOO LOW
SEAT WIDTH
TOO HIGH
8-19