Honda NSS250S Manual page 312

CYLINDER HEAD/VALVES
Using a 45° seat cutter, remove any roughness or
Reface the seat
with a 45 ° cutter
irregularities from the seat.
whenever a valve
TOOLS:
guide is replaced.
Seat cutter, 29 mm (45° IN)
Seat cutter, 24.5 mm (45° EX)
Cutter holder
Using a 32° flat cutter, remove the top 1/4 of the
existing valve seat material.
TOOLS:
Flat cutter, 29 mm (32° IN)
Flat cutter, 25 mm (32° EX)
Cutter holder
Using a 60° interior cutter, remove the bottom 1/4 of
the existing valve seat material.
TOOLS:
Interior cutter, 26 mm (60° IN)
Interior cutter, 24 mm (60° EX)
Cutter holder
Using a 45° seat cutter, cut the seat to the proper
width.
VALVE SEAT WIDTH: 0.90 – 1.10 mm
Make sure that all pitting and irregularities are
removed.
9-18
maxiscooter-club.ru
07780-0010300
07780-0010100
07781-0010600
07780-0013400
07780-0012000
07781-0010600
07780-0014500
070PH-Z0D0100
07781-0010600
(0.035 – 0.043 in)
ROUGHNESS
OLD SEAT
WIDTH
32°
OLD SEAT
WIDTH
60°
0.90 – 1.10 mm
(0.035 – 0.043 in)
45°