Yamaha F15MHX Manuel D'entretien page 240

POWR
2
3
4
CAMSHAFT AND VALVES
2 The valve seat is in the middle of the valve
face, but is too narrow.
Valve seat cutter set
Use 45° cutter
3 The valve seat is too narrow and is near the
valve margin.
Valve seat cutter set
First:
90° cutter
Use
Second:
45° cutter
4 The valve seat is too narrow and is near the
bottom edge of the valve face.
Valve seat cutter set
First:
30° cutter
Use
Second:
45° cutter
5-29
E
Desired result
To achieve a
uniform valve
seat width.
Desired result
To achieve a
Centered valve
seat with the
proper width.
Desired result
To center the
valve seat and
increase its
width.