KYMCO 125 MOVIE S INJECTION, Manual

Page: 86 / 213

7
. CYLINDER HEAD/VALVES
7-12
Inspect the valve seat contact area.
If the contact area is too high on the valve, the
seat must be lowered using a 32
°
cutter.
If the contact area is too low on the valve, the
seat must be raised using a 60
°
cutter.
Refinish the seat to specifications using a 45
°
seat cutter.
After cutting the seat, apply emery to each
valve contact face and lap the valve.
After lapping, wash all residuals off the
cylinder head and valves.
After refacing and lapping, apply red lead to
the 45
°
valve seat to make sure that the center
of the valve contact face is even.
CYLINDER HEAD ASSEMBLY
Install the valve spring seats and valve stem
seals.
Lubricate each valve stem with engine oil and
insert the valves into the valve guides.
Install the valve springs and retainers.
Compress the valve springs using the valve
spring compressor, then install the valve
cotters.
Valve Spring Compressor
Valve Spring Compressor Attachment
Be sure to install new valve stem seals.
＊
Old Seat Width
Old Seat Width
Contact too High
Contact too
Low
Valve Spring Compressor
•
When lapping, use a light
pressure and avoid damaging the valve
seat due to forcedly lapping.
•
Use care not to allow emery to
enter the valve stem and guide.
＊
•
When assembling, a valve spring
compressor must be used.
•
Install the cotters with the
pointed ends facing down from the
upper side of the cylinder head.
＊
Special
Special
Valve Spring Compressor
Attachment