Montesa COTA 301RR 2023, Owner'S Manual

Page: 93 / 180

Engine servicing
4-30 4-30
Use a interior cutter, remove 1/4 of the existing valve
seat material.
Tools:
Interior cutter, 26 mm 07780-0014500
Interior cutter, 22 mm 07780-0014202
Cutter holder, 4.5 mm 07781-0010600
or equivalent commercially available
Use a 32 ˚ flat cutter, remove 1/4 of the existing valve
seat material.
Tools:
Flat cutter, 25 mm 07780-0012000
Flat cutter, 21.5 mm 07780-0012800
Cutter holder, 4.5 mm 07781-0010600
or equivalent commercially available
Use a 45 ˚ cutter, remove any roughness or irregularities
from the seat.
Reface the seat with a 45 ˚ cutter whenever a valve guide
is replaced.
Tools:
Seat cutter, 24.5 mm 07780-0010100
Seat cutter, 22 mm 07780-0010701
Cutter holder, 4.5 mm 07781-0010600
or equivalent commercially available
(1) SEAT WIDTH
45º
32º
60º
1