Honda TRX450R Service Manual page 216

CYLINDER HEAD/VALVE
REFACING
NOTE:
• Follow the refacer manufacturer's operating
instructions.
• Be careful not to grind the seat more than neces-
say.
If the contact area is too high on the valve, the seat
must be lowered using a 32° flat cutter.
If the contact area is too low on the valve, the seat
must be raised using a 60° interior cutter.
Use a 45° seat cutter to remove any roughness or
irregularities from the seat.
TOOLS:
Seat cutter, 35 mm (45° IN)
Seat cutter, 33 mm (45° EX)
Cutter holder, 5.5 mm (IN)
Cutter holder, 5.0 mm
(After '05; EX)
07780-0010400
07780-0010800
07781-0010101
07781-0010400
or equivalent commercially available in U.S.A.
Using a 32° flat cutter, remove 1/4 of the existing
valve seat material.
TOOLS:
Flat cutter, 36 mm (32° IN)
Flat cutter, 33 mm (32° EX)
Cutter holder, 5.5 mm (IN)
Cutter holder, 5.0 mm
(After '05; EX)
07780-0013500
07780-0012900
07781-0010101
07781-0010400
or equivalent commercially available in U.S.A.
CONTACT TOO HIGH
OLDSEAT
WIDTH
CONTACT TOO LOW
OLDSEAT
WIDTH
60°
ROUGHNESS
OLD SEAT WIDTH
11-21