Yamaha QT 50F Service Manual page 33

1. Reed valve assembly
2. Reed valve
3. Reed valve stopper
4. Panhead screw
5. Spring washer
6. Reed valve plate
7. Valve seat packing 1
8. Valve seat packing 2
9. Manifold
10. Panhead screw
4. Valve stopper
The valve stopper controls the move-
ment of the valve. Check clearance "a".
Valve stopper clearance:
4.8±0.2 mm (0.19±0.008 in)
Read distortion limit: 0.3 mm (0.012 in)
NOTE:
If clearance "a" is larger than specified, the
valve will be broken. If smaller, engine per-
formance can be impaired.
Valve stopper screw torque:
0.08 m-kg (0.6 ft-lb)
5. Reed valve
a. Place the reed valve on a surface plate,
with the reverse side down, and
measure the amount of warpage. If
measured more than the limit, the reed
valve should be replaced.
^ ^ ^ 0.8 m m (0.03 in)
Surface Plate
Warpage limit: 0.8 mm (0.03 in)
b. There should be no gap between the
reed valve end and valve seat, when it is
installed.
1. Valve seat 3. Reed valve
2. Reed valve stopper
(0.19 in)
4-4