Yamaha F6AMH Manuel D'entretien page 360

BACKLASH
Backlash indicator:
YB-06265/90890-06706
Magnet base:
YU-34481/90890-06705
Magnetic base attaching plate:
YB-07003/90890-07003
Dial gauge stand:
YU-03097/90890-01252
(5)While pulling the drive shaft
downward, slowly turn the drive shaft
clockwise and counterclockwise then
measure the backlash when the drive
shaft stops at each direction.
(6)Determine the shims to be added or
removed according to the specified.
Reverse gear
backlash
Less than
1.01 mm (0.0398 in)
More than
1.38 mm (0.0543 in)
Available shim thickness: 0.10
NOTE:
Since the smallest shim available is
0.10 mm, if the measurement is between
1.01 mm and 1.38 mm, do not change the
shim.
6-26
Shim thickness
To be decreased by
(1.2 - Measurement)
2.52
To be increased by
(Measurement - 1.2)
2.52