Exchange Of Gear Reduction Ratio - Rotax 125 DD2 MAX EVO Operator's Manual

Gear ratio 2
Number
of teeth of
primary
drive gear
NOTE
To facilitate the change of gear ratio, it is recommended to carry a clutch drum
with a primary drive gear and the respective secondary gear for each gear ratio.
NOTE
To allow easier matching of primary and secondary gears, please note that the
sum of the last digits of the teeth number must always be 7 or 17 (35 / 62).

EXCHANGE OF GEAR REDUCTION RATIO

Tools required:
• Torque wrench
• Allen key 5 mm
• Allen key 6 mm
At first glance, the exchange of the gear ratio seems to be more complicated than you are
used to. If, however, you follow the hints below, you will notice that the work involved is not
much different.
Effectivity: 125 MAX DD2 evo
BRP-Rotax
Operators Manual
nd gear
Number of
teeth of
secondary
drive gear
36 61
37 60
38 59
gear ratio of 2 nd gear
(cannot be changed)
Step Procedure
1 Lift engine side of the kart and place the vehicle on a trolley.
2 Remove the right rear hub with wheel.
3 Unscrew 4 Allen screws M6x30 (pos. 1), 4 Allen screws M8x70 (pos. 2) and
2 Allen screws M6x40 (pos. 3). Remove the gear cover.
NOTE
If the gear cover is difficult to remove, it can be levered off at the sep-
arating lugs.
Gear ratio Traditional
gear ratio
(in sprocket
size)
5.44 14 to 76
5.21 14 to 73
4.98 15 to 75
3.21
Theoretical max. speed
(in km/h / mile/h) (at
12.500 rpm and wheel
diameter 870 mm /34.25
in.)
120 / 75
125 / 78
131 / 81
Page 17
Edition: March 01 2021
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