66
Checking Backlash
NOTE: The rear shaft and bevel gear must be
removed for this procedure. Also, always start with
the original shims on the rear shaft.
1. Place the left-side crankcase cover onto the
left-side crankcase half to prevent runout of the
secondary transmission output shaft.
2. Install the secondary driven output shaft assembly
onto the crankcase.
3. Mount the indicator tip of the dial indicator on the
secondary driven bevel gear (centered on the gear
tooth).
4. While rocking the driven bevel gear back and
forth, note the maximum backlash reading on the
gauge.
5. Acceptable backlash range is 0.05-0.33 mm
(0.002-0.013 in.).
Correcting Backlash
NOTE: If backlash measurement is within the
acceptable range, no correction is necessary.
1. If backlash measurement is less than specified,
remove an existing shim, measure it, and install a
new thinner shim.
2. If backlash measurement is more than specified,
remove an existing shim, measure it, and install a
thicker shim.
NOTE: Continue to remove, measure, and install
until backlash measurement is within tolerance.
Note the following chart.
Checking Tooth Contact
NOTE: After correcting backlash of the second-
ary driven bevel gear, it is necessary to check
tooth contact.
1. Remove the secondary driven output shaft assem-
bly from the left-side crankcase half.
2. Clean the secondary driven bevel gear teeth of old
oil and grease residue.
3. Apply a thin, even coat of a machinist-layout dye
to several teeth of the gear.
4. Install the secondary driven output shaft assembly.
5. Rotate the secondary driven bevel gear several
revolutions in both directions.
6. Examine the tooth contact pattern in the dye and
compare the pattern to the illustrations.
ATV-0103
ATV-0105
ATV-0104
Correcting Tooth Contact
NOTE: If tooth contact pattern is comparable to
the correct pattern illustration, no correction is
necessary.
If tooth contact pattern is comparable to an incorrect
pattern, correct tooth contact according to the follow-
ing chart.
Backlash Measurement
Shim Correction
Under 0.05 mm (0.002 in.)
Decrease Shim
Thickness
At 0.05-0.33 mm
(0.002-0.013 in.)
No Correction Required
Over 0.33 mm (0.013 in.)
Increase Shim
Thickness
Tooth Contact
Shim Correction
Contacts at Top
Decrease Shim Thickness
Contacts at Root
Increase Shim Thickness