Rotax 125 DD2 MAX EVO Operator's Manual page 36

If these gear ratios are still not sufficient, try the next shorter or next longer gear ratio.
NOTE
When using short gear ratios, it may happen that the response behavior of the en-
gine in 1
good lap time, often a longer gear ratio is helpful to achieve reasonable perform-
ance behavior.
NOTE
To help with the choice of adequate gear ratios, the two charts below illustrate the
traditional gear ratios and the top speeds in [kmh] that can be reached in the re-
spective gear at an engine speed of 12.500 rpm.
Gear ratio 1
Number
of teeth of
primary
drive gear
Gear ratio 2
Number
of teeth of
primary
drive gear
3
Page 16
Edition: March 01 2021
BRP-Rotax
Operators Manual
st gear is aggressive and the vehicle handling becomes difficult. For a
st gear
Number of
teeth of
secondary
drive gear
32 65
33 64
34 63
35 62
36 61
37 60
38 59
gear ratio of 1 st gear
(cannot be changed)
nd gear
Number of
teeth of
secondary
drive gear
32 65
33 64
34 63
35 62
Gear ratio Traditional
gear ratio
(in sprocket
size)
8.65 10 to 87
8.26 11 to 91
7.89 11 to 87
7.55 12 to 90
7.22 12 to 87
6.91 12 to 83
6.61 12 to 80
4.26
Gear ratio Traditional
gear ratio
(in sprocket
size)
6.52 14 to 91
6.23 14 to 87
5.95 14 to 83
5.69 14 to 79
Theoretical max. speed
(in km/h / mile/h) (at
12.500 rpm and wheel
diameter 870 mm /34.25
in.)
75 / 47
79 / 49
83 / 52
86 / 53
90 / 56
94 / 58
99 / 62
Theoretical max. speed
(in km/h / mile/h) (at
12.500 rpm and wheel
diameter 870 mm /34.25
in.)
100 / 62
105 / 65
110 / 68
115 / 72
Effectivity: 125 MAX DD2 evo