Suzuki GSX-R750 Service Manual page 86

3-38 ENGINE
INITIAL SEAT CUT
• Using the 45° cutter, descale and clean up the seat. Rotate the
cutter one or two turns.
• Measure the valve seat width W after every cut.
• If the valve seat is pitted or burned, use the 45° cutter to condi-
tion the seat some more.
NOTE:
Cut only the minimum amount necessary from the seat to pre-
vent the possibility of the valve stem becoming too close to the
camshaft.
TOP NARROWING CUT
• If the contact area W is too high on the valve, or if it is too wide,
use the 15° (for the exhaust side) and the 30° (for the intake
side) to lower and narrow the contact area.
BOTTOM NARROWING CUT
• If the contact area W is too wide or too low, use the 60° cutter
to narrow and raise the contact area.
Contact area too high and too
wide on face of valve