Suzuki UY125 Service Manual page 62

3-28 ENGINE
• Seat the pilot snugly. Install the 45° cutter 3, attachment and
T-handle 4.
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 con-
dition 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
rocker arm for correct valve contact angle.
TOP NARROWING CUT
• If the contact area W is too high on the valve, or if it is too
wide, use the 15° (for exhaust side) and the 30° (for the intake
side) to lower and narrow the contact area.
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45˚
15˚: For exhaust
30˚: For intake