Suzuki DR650SE - Page 60

3·23 ENGINE
If the contact area is too high on the valve, or if it is too
wide, use the 15
0
cutter to lower and narrow the contact
area.
If the contact area is too low or too narrow, use the 45
0
cutter to raise and widen the contact area.
• After the desired seat position and width is achieved, use
the 45
0
cutter very lightly to clean up and burrs caused
by the previous cutting operations.
] ACAUTION]
DO NOT use lapping compound after the final cut is
made. The finished valve seat should have a velvety
smooth finish and not a highly polished or shiny finish.
This will provide a soft surface for the final seating of
the valve which will occur during the first few seconds
of engine operation.
• Clean and assemble the head and valve components. Fill
the intake and exhaust ports with gasoline to check for
leaks. If any leaks occur, inspect the valve seat and face
for burrs or other things that could prevent the valve from
sealing.
A WARNING
Always use extreme caution when handling gasoline.
NOTE:
After servicing the valve seats, be sure to check the valve
clearance after the cylinder head has been reinstalled. (Refer
to
page 2-3.)
Contact area too high and too
wide on face of valve
Contact area too low and too
narrow on face of valve