rear sprocket

hi,my xrr has a 13t front and a 45t rear, as i bought it, have been told this works out same as stock
happy with the bike as is, it came with spare 48t, was wondering what difference this would make, with the 13t on front
any help would be great....

14~48 is stock so that's same as 13~45...1 off the front is same as 3 off the rear.

SPROCKET MATH

Calculating the sprocket drive ratio:

(Rear tooth count) / (front tooth count) = drive ratio

Example 1:
Bike ships stock with 47 tooth rear sprocket, 15 tooth front sprocket.
47 / 15 = 3.13333
So 3.13333 is the stock sprocket ratio.

Example 2:
You buy a 50 tooth rear sprocket and a 15 tooth front sprocket for the above bike.
50 / 15 = 3.33333
So 3.33333 is the new sprocket ratio.



GEARING CALCULATION HELP

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
9 1.00
10 1.11 1.00
11 1.22 1.10 1.00
12 1.33 1.20 1.09 1.00
13 1.44 1.30 1.18 1.08 1.00
14 1.56 1.40 1.27 1.17 1.08 1.00
15 1.67 1.50 1.36 1.25 1.15 1.07 1.00
16 1.78 1.60 1.45 1.33 1.23 1.14 1.07 1.00
17 1.89 1.70 1.55 1.42 1.31 1.21 1.13 1.06 1.00
18 2.00 1.80 1.64 1.50 1.38 1.29 1.20 1.13 1.06 1.00
19 2.11 1.90 1.73 1.58 1.46 1.36 1.27 1.19 1.12 1.06 1.00
20 2.22 2.00 1.82 1.67 1.54 1.43 1.33 1.25 1.18 1.11 1.05 1.00
21 2.33 2.10 1.99 1.75 1.62 1.50 1.40 1.31 1.24 1.17 1.11 1.05 1.00
22 2.44 2.20 2.00 1.83 1.69 1.57 1.47 1.38 1.29 1.22 1.16 1.10 1.05 1.00
23 2.56 2.30 2.09 1.92 1.77 1.64 1.53 1.44 1.35 1.28 1.21 1.15 1.10 1.05 1.00
24 2.67 2.40 2.18 2.00 1.85 1.71 1.60 1.50 1.41 1.33 1.26 1.20 1.14 1.09 1.04 1.00
25 2.78 2.50 2.27 2.08 1.92 1.79 1.67 1.56 1.47 1.39 1.32 1.25 1.19 1.14 1.09 1.04 1.00
26 2.89 2.60 2.36 2.17 2.00 1.86 1.73 1.63 1.53 1.44 1.37 1.30 1.24 1.18 1.13 1.08 1.04 1.00
27 3.00 2.70 2.45 2.25 2.08 1.93 1.80 1.69 1.59 1.50 1.42 1.35 1.29 1.23 1.17 1.13 1.08 1.04
28 3.11 2.800 2.55 2.33 2.15 2.00 1.87 1.75 1.65 1.56 1.47 1.40 1.33 1.27 1.22 1.17 1.12 1.08
29 3.22 2.90 2.64 2.42 2.23 2.07 1.93 1.81 1.71 1.61 1.53 1.45 1.38 1.32 1.26 1.21 1.16 1.12
30 3.33 3.00 2.73 2.50 2.31 2.14 2.00 1.88 1.77 1.67 1.58 1.50 1.43 1.36 1.30 1.25 1.20 1.15
31 3.44 3.10 2.82 2.58 2.39 2.21 2.07 1.94 1.82 1.72 1.63 1.55 1.48 1.41 1.35 1.29 1.24 1.19
32 3.56 2.20 2.91 2.67 2.46 2.29 2.13 2.00 1.88 1.78 1.68 1.60 1.52 1.46 1.39 1.33 1.28 1.23
33 3.67 3.30 3.00 2.75 2.54 2.36 2.20 2.06 1.94 1.83 1.74 1.65 1.57 1.50 1.43 1.38 1.32 1.27
34 3.78 3.40 3.09 2.83 2.62 2.43 2.27 2.13 2.00 1.89 1.79 1.70 1.62 1.55 1.48 1.42 1.36 1.31
35 3.89 3.50 3.18 2.92 2.69 2.50 2.33 2.19 2.06 1.94 1.84 1.75 1.67 1.59 1.52 1.46 1.40 1.35
36 4.00 3.60 3.27 3.00 2.77 2.57 2.40 2.25 2.12 2.00 1.89 1.80 1.71 1.64 1.57 1.50 1.44 1.38
37 4.11 3.70 3.36 3.08 2.85 2.64 2.47 2.31 2.18 2.06 1.95 1.85 1.76 1.68 1.61 1.54 1.48 1.42
38 4.22 3.80 3.45 3.17 2.92 2.71 2.53 2.38 2.24 2.11 2.00 1.90 1.81 1.73 1.65 1.58 1.52 1.46
39 4.33 3.90 3.55 3.25 3.00 2.79 2.60 2.44 2.29 2.17 2.05 1.95 1.86 1.77 1.70 1.63 1.56 1.50
40 4.44 4.00 3.64 3.33 3.08 2.86 2.67 2.50 2.35 2.22 2.11 2.00 1.91 1.82 1.74 1.67 1.60 1.54
41 4.56 4.10 3.73 3.42 3.15 2.93 2.73 2.56 2.41 2.28 2.16 2.05 1.95 1.86 1.78 1.71 1.64 1.58
42 4.67 4.200 3.818 3.500 3.231 3.000 2.800 2.625 2.471 2.333 2.211 2.100 2.000 1.909 1.826 1.75 1.68 1.62
43 4.78 4.300 3.909 3.583 3.308 3.071 2.867 2.688 2.529 2.389 2.263 2.150 2.048 1.955 1.870 1.79 1.72 1.65
44 4.89 4.400 4.000 3.667 3.385 3.143 2.933 2.750 2.588 2.444 2.316 2.200 2.095 2.000 1.913 1.83 1.76 1.69
45 5.00 4.500 4.091 3.750 3.462 3.214 3.000 2.813 2.647 2.500 2.368 2.250 2.143 2.045 1.957 1.88 1.80 1.73
46 5.11 4.600 4.182 3.833 3.538 3.286 3.067 2.875 2.706 2.556 2.421 2.300 2.190 2.091 2.000 1.92 1.84 1.77
47 5.22 4.700 4.273 3.917 3.615 3.357 3.133 2.938 2.765 2.611 2.474 2.350 2.238 2.136 2.043 1.96 1.88 1.81
48 5.33 4.800 4.364 4.000 3.692 3.429 3.200 3.000 2.824 2.667 2.526 2.400 2.286 2.182 2.087 2.00 1.92 1.85
49 5.44 4.900 4.455 4.083 3.769 3.500 3.267 3.063 2.882 2.722 2.579 2.450 2.333 2.227 2.130 2.04 1.96 1.88
50 5.56 5.000 4.545 4.167 3.846 3.571 3.333 3.125 2.941 2.778 2.632 2.500 2.381 2.273 2.174 2.08 2.00 1.92
51 5.67 5.100 4.636 4.250 3.923 3.643 3.400 3.188 3.000 2.833 2.684 2.550 2.429 2.318 2.217 2.13 2.04 1.96
52 5.78 5.20 4.73 4.33 4.00 3.71 3.47 3.25 3.06 2.89 2.74 2.60 2.48 2.36 2.26 2.17 2.08 2.00
53 5.89 5.30 4.82 4.42 4.08 3.79 3.53 3.31 3.12 2.94 2.79 2.65 2.52 2.41 2.30 2.21 2.12 2.04
54 6.00 5.40 4.91 4.50 4.15 3.86 3.60 3.38 3.18 3.00 2.84 2.70 2.57 2.46 2.35 2.25 2.16 2.08
55 6.11 5.50 5.00 4.58 4.23 3.93 3.67 3.44 3.24 3.06 2.90 2.75 2.62 2.50 2.39 2.29 2.20 2.12
56 6.22 5.60 5.09 4.67 4.31 4.00 3.73 3.50 3.29 3.11 2.95 2.80 2.67 2.55 2.43 2.33 2.24 2.15
57 6.33 5.70 5.18 4.75 4.39 4.07 3.80 3.56 3.35 3.17 3.00 2.85 2.71 2.59 2.48 2.38 2.28 2.19
58 6.44 5.80 5.27 4.83 4.46 4.14 3.87 3.63 3.41 3.22 3.05 2.90 2.76 2.64 2.52 2.42 2.32 2.23
59 6.56 5.90 5.36 4.92 4.54 4.21 3.93 3.69 3.47 3.28 3.11 2.95 2.81 2.68 2.57 2.46 2.36 2.27
60 6.67 6.00 5.46 5.00 4.62 4.29 4.00 3.75 3.53 3.33 3.16 3.00 2.86 2.73 2.61 2.50 2.40 2.31
68 7.56 6.80 6.18 5.67 5.23 4.86 4.53 4.25 4.00 3.78 3.58 3.40 3.24 3.09 2.96 2.83 2.72 2.62
70 7.78 7.00 6.36 5.83 5.39 5.00 4.67 4.38 4.12 3.89 3.68 3.50 3.33 3.18 3.04 2.92 2.80 2.69
72 8.00 7.20 6.55 6.00 5.54 5.14 4.80 4.50 4.24 4.00 3.79 3.60 3.43 3.27 3.13 3.00 2.88 2.77
76 8.44 7.60 6.91 6.33 5.85 5.43 5.07 4.75 4.47 4.22 4.00 3.80 3.62 3.45 3.30 3.17 3.04 2.92
80 8.89 8.00 7.27 6.67 6.15 5.71 5.33 5.00 4.71 4.44 4.21 4.00 3.81 3.64 3.48 3.33 3.20 3.08
84 9.33 8.40 7.64 7.00 6.46 6.00 5.60 5.25 4.94 4.67 4.42 4.20 4.00 3.82 3.65 3.50 3.36 3.23
95 10.56 9.50 8.64 7.92 7.31 6.79 6.33 5.94 5.59 5.28 5.00 4.75 4.52 4.32 4.13 3.96 3.80 3.65
96 10.67 9.60 8.73 8.00 7.38 6.86 6.40 6.00 5.65 5.33 5.05 4.80 4.57 4.36 4.17 4.00 3.84 3.69
102 11.33 10.20 9.27 8.50 7.85 7.29 6.80 6.38 6.00 5.67 5.37 5.10 4.86 4.64 4.43 4.25 4.08 3.92
112 12.44 11.20 10.18 9.33 8.62 8.00 7.47 7.00 6.59 6.22 5.89 5.60 5.33 5.09 4.87 4.67 4.48 4.31
Note:
Bigger number = Shorter Gearing = Higher RPM's
Smaller number = Taller Gearing = Lower RPM's

A 'Shorter' Gear Ratio is better for more torque, acceleration, wheelies, and racetracks with short straights.

A 'Taller' Gear Ratio is better for open-rode cruising, lower rpm's, better gas mileage, and tracks with long straights.

dougyfresh wrote:hi,my xrr has a 13t front and a 45t rear, as i bought it, have been told this works out same as stock
happy with the bike as is, it came with spare 48t, was wondering what difference this would make, with the 13t on front
any help would be great....

Great for wheelies.