KEEWAY ATV300, User Manual

Page: 41 / 110

41
Use 60° cutter to cut a quarter lower parts out.
Remove the cutter and check new valve seat.
Use 45° cutter to grind the valve seat to specified
Width
Caution
Grind valve seat again if necessary.
Coat the valve seat surface with red paint.
Install the valve through valve guide until the
valve contacting with valve seat, slightly press
down the valve but do not rotate it so that a seal
track will be created on contact surface.
Caution
If the contact surface too high, grind the valve seat
with 32° cutter.
Then, grind the valve seat to specified width.
If the contact surface too low, grind the valve
seat with 60° cutter.
Then, grind the valve seat to specified width
Make sure that all roughness and uneven
faces had been ground
The contact surfaces of valve and valve seat
are very important to the valve sealing
capacity.
.
Old valve seat width
60°
1.0mm
45°
Contact surface too high Old valve seat width
32°
Contact surface too low Old valve seat width
60°