Selva Narwhal 115 Manuel D'entretien page 410

LOWR
SHIMMING (REGULAR ROTATION MODELS)
(FOR USA AND CANADA)
6780
6790
6800
SELECTING THE FORWARD GEAR
SHIMS
NOTE:
Find the shim thickness (T1) by selecting
shims until the specified value (M0) is
obtained with the special tool.
1. Measure:
• Specified measurement (M)
Out of specified value (M0) → Adjust.
Specified value (M0) =
1.80 + F/100 mm
Measuring steps
(1) Calculate the specified value (M0).
NOTE:
"F" is the deviation of the lower case
dimension from standard. It is stamped on
the trim tab mounting surface of the lower
case in 0.01-mm units. If the "F" mark is
missing or unreadable, assume an "F"
value of "0", and check the backlash when
the unit is assembled.
Example:
If "F" is "+5", then
M0 = 1.80 + (+5)/100 mm
= 1.80 + 0.05 mm
= 1.85 mm
If "F" is "–3", then
M0 = 1.80 + (–3)/100 mm
= 1.80 – 0.03 mm
= 1.77 mm
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E
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