Honda SH300I 2006, Manual

Page: 233 / 511

CYLINDER HEAD/VALVES
9-17
Using a 32
°
flat cutter, remove 1/4 of the existing
valve seat material.
Using a 60
°
interior cutter, remove 1/4 of the exist-
ing valve seat material.
Using a 45
°
seat cutter, cut the seat to the proper
width.
Make sure that all pitting and irregularities are
removed.
After cutting the seat, apply lapping compound to
the valve face, and lap the valve using light pres-
sure.
• Excessive lapping pressure may deform or dam-
age the seat.
• Change the angle of the lapping tool frequently
to prevent uneven seat wear.
• Do not allow lapping compound to enter the
guides.
After lapping, wash any residual compound off the
cylinder head and valve and recheck the seat con-
tact.
TOOLS:
Flat cutter, 29 mm (32
°
IN) 07780-0013400
Flat cutter, 25 mm (32
°
EX) 07780-0012000
Cutter holder, 4.5 mm 07781-0010600
or equivalent commercially available
OLD SEAT WIDTH
32
°
TOOLS:
Interior cutter, 26 mm (60
°
IN) 07780-0014500
Interior cutter, 22 mm (60
°
EX) 07780-0014202
Cutter holder, 4.5 mm 07781-0010600
or equivalent commercially available
60
°
OLD SEAT WIDTH
VALVE SEAT WIDTH: 0.90 – 1.10 mm (0.035 – 0.043 in)
SEAT WIDTH
45
°
VALVE