Yamaha FT60D - Page 119

6C13G11
5-28
1
2
3
4
5
6
7
8
9
b
Previous contact width
4. Use a 60° cutter to adjust the contact
width of the bottom edge of the valve
seat.
b
Previous contact width
5. Use a 45° cutter to adjust the contact
width of the valve seat to specification.
b
Previous contact width
c
Specified contact width
6. If the valve seat contact area is too wide
and situated in the center of the valve
face, use a 30° cutter to cut the top edge
of the valve seat and a 60° cutter to cut
the bottom edge to center the area and
set its width.
b
Previous contact width
7. If the valve seat contact area is too nar-
row and situated near the top edge of the
valve face, use a 30° cutter to cut the top
edge of the valve seat. If necessary, use
a 45° cutter to center the area and set its
width.
b
Previous contact width
8. If the valve seat contact area is too nar-
row and situated near the bottom edge of
the valve face, use a 60° cutter to cut the
bottom edge of the valve seat. If neces-
sary, use a 45° cutter to center the area
and set its width.
b
Previous contact width
S69J5880
30˚
b
S69J5890
60˚
b
S69J5900
45˚
b
c
Cylinder head