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GEAR
RATIOS FOR COBRI GEARBOXES |
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(Assumes availablity of Spurs and
Pinions to fit) |
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Spur Gear |
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60 |
62 |
64 |
66 |
68 |
70 |
72 |
74 |
76 |
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9 |
6.67 |
6.89 |
7.11 |
7.33 |
7.56 |
7.78 |
8.00 |
8.22 |
8.44 |
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10 |
6.00 |
6.20 |
6.40 |
6.60 |
6.80 |
7.00 |
7.20 |
7.40 |
7.60 |
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11 |
5.45 |
5.64 |
5.82 |
6.00 |
6.18 |
6.36 |
6.55 |
6.73 |
6.91 |
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12 |
5.00 |
5.17 |
5.33 |
5.50 |
5.67 |
5.83 |
6.00 |
6.17 |
6.33 |
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13 |
4.62 |
4.77 |
4.92 |
5.08 |
5.23 |
5.38 |
5.54 |
5.69 |
5.85 |
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14 |
4.29 |
4.43 |
4.57 |
4.71 |
4.86 |
5.00 |
5.14 |
5.29 |
5.43 |
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15 |
4.00 |
4.13 |
4.27 |
4.40 |
4.53 |
4.67 |
4.80 |
4.93 |
5.07 |
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16 |
3.75 |
3.88 |
4.00 |
4.13 |
4.25 |
4.38 |
4.50 |
4.63 |
4.75 |
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17 |
3.53 |
3.65 |
3.76 |
3.88 |
4.00 |
4.12 |
4.24 |
4.35 |
4.47 |
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18 |
3.33 |
3.44 |
3.56 |
3.67 |
3.78 |
3.89 |
4.00 |
4.11 |
4.22 |
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19 |
3.16 |
3.26 |
3.37 |
3.47 |
3.58 |
3.68 |
3.79 |
3.89 |
4.00 |
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20 |
3.00 |
3.10 |
3.20 |
3.30 |
3.40 |
3.50 |
3.60 |
3.70 |
3.80 |
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22 |
2.73 |
2.82 |
2.91 |
3.00 |
3.09 |
3.18 |
3.27 |
3.36 |
3.45 |
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24 |
2.50 |
2.58 |
2.67 |
2.75 |
2.83 |
2.92 |
3.00 |
3.08 |
3.17 |
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26 |
2.31 |
2.38 |
2.46 |
2.54 |
2.62 |
2.69 |
2.77 |
2.85 |
2.92 |
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Pinion
Gear |
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Ratio |
Spur |
Pinion |
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8.44 |
76 |
9 |
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8.22 |
74 |
9 |
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8.00 |
72 |
9 |
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7.78 |
70 |
9 |
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7.60 |
76 |
10 |
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7.56 |
68 |
9 |
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7.40 |
74 |
10 |
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7.33 |
66 |
9 |
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7.20 |
72 |
10 |
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7.11 |
64 |
9 |
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7.00 |
70 |
10 |
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6.91 |
76 |
11 |
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6.89 |
62 |
9 |
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6.80 |
68 |
10 |
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6.73 |
74 |
11 |
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6.67 |
60 |
9 |
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6.60 |
66 |
10 |
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6.55 |
72 |
11 |
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6.40 |
64 |
10 |
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6.36 |
70 |
11 |
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6.33 |
76 |
12 |
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6.20 |
62 |
10 |
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6.18 |
68 |
11 |
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6.17 |
74 |
12 |
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6.00 |
72 |
12 |
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6.00 |
66 |
11 |
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6.00 |
60 |
10 |
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5.85 |
76 |
13 |
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5.83 |
70 |
12 |
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5.82 |
64 |
11 |
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5.69 |
74 |
13 |
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5.67 |
68 |
12 |
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5.64 |
62 |
11 |
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5.54 |
72 |
13 |
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5.50 |
66 |
12 |
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5.45 |
60 |
11 |
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5.43 |
76 |
14 |
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5.38 |
70 |
13 |
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5.33 |
64 |
12 |
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5.29 |
74 |
14 |
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5.23 |
68 |
13 |
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5.17 |
62 |
12 |
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5.14 |
72 |
14 |
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5.08 |
66 |
13 |
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5.07 |
76 |
15 |
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5.00 |
70 |
14 |
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5.00 |
60 |
12 |
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4.93 |
74 |
15 |
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4.92 |
64 |
13 |
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4.86 |
68 |
14 |
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4.80 |
72 |
15 |
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4.77 |
62 |
13 |
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4.75 |
76 |
16 |
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4.71 |
66 |
14 |
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4.67 |
70 |
15 |
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4.63 |
74 |
16 |
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4.62 |
60 |
13 |
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4.57 |
64 |
14 |
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4.53 |
68 |
15 |
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4.50 |
72 |
16 |
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4.47 |
76 |
17 |
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4.43 |
62 |
14 |
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4.40 |
66 |
15 |
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4.38 |
70 |
16 |
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4.35 |
74 |
17 |
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4.29 |
60 |
14 |
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4.27 |
64 |
15 |
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4.25 |
68 |
16 |
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4.24 |
72 |
17 |
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4.22 |
76 |
18 |
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4.13 |
62 |
15 |
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4.13 |
66 |
16 |
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4.12 |
70 |
17 |
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4.11 |
74 |
18 |
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4.00 |
76 |
19 |
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4.00 |
72 |
18 |
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4.00 |
68 |
17 |
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4.00 |
64 |
16 |
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4.00 |
60 |
15 |
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3.89 |
74 |
19 |
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3.89 |
70 |
18 |
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3.88 |
66 |
17 |
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3.88 |
62 |
16 |
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3.80 |
76 |
20 |
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3.79 |
72 |
19 |
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3.78 |
68 |
18 |
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3.76 |
64 |
17 |
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3.75 |
60 |
16 |
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3.70 |
74 |
20 |
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3.68 |
70 |
19 |
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3.67 |
66 |
18 |
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3.65 |
62 |
17 |
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3.60 |
72 |
20 |
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3.58 |
68 |
19 |
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3.56 |
64 |
18 |
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3.53 |
60 |
17 |
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3.50 |
70 |
20 |
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3.47 |
66 |
19 |
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3.44 |
62 |
18 |
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3.40 |
68 |
20 |
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3.37 |
64 |
19 |
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3.33 |
60 |
18 |
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3.30 |
66 |
20 |
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3.26 |
62 |
19 |
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3.20 |
64 |
20 |
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3.16 |
60 |
19 |
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3.10 |
62 |
20 |
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3.00 |
60 |
20 |
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Copyright 2007 - Andy Steere
Last modified on 02/05/2007