gears.py is a very simple python script used to compare different bike gear sets. You can input any number of tooth gears front and back, see how many are duplicated, how many are are usable... usage: ./gears.py -c 30,42,52 -o 12,13,14,15,17,19,21,23,26 and you will get an output like this: 30x26 01.15 08.36mph 30x23 01.30 09.45mph 30x21 01.43 10.36mph 30x19 01.58 11.45mph 30x17 01.76 12.79mph 30x15 02.00 14.50mph 42x21, 52x26 30x14 02.14 15.53mph - 30x13 02.31 16.73mph - 30x12 02.50 18.12mph X 42x26 01.62 11.71mph 42x23 01.83 13.24mph 42x21 02.00 14.50mph 30x15, 52x26 42x19 02.21 16.02mph 52x23 42x17 02.47 17.91mph 52x21 42x15 02.80 20.30mph 42x14 03.00 21.75mph 52x17 42x13 03.23 23.42mph 42x12 03.50 25.37mph 52x26 02.00 14.50mph X 30x15, 42x21 52x23 02.26 16.39mph - 42x19 52x21 02.48 17.95mph - 42x17 52x19 02.74 19.84mph 52x17 03.06 22.17mph 42x14 52x15 03.47 25.13mph 52x14 03.71 26.92mph 52x13 04.00 28.99mph 52x12 04.33 31.41mph Summary gear: 27 unique gears: 22 usable gears: 21 unique usable gears: 19 percent unique usable gears: 70.37% max speed: 31.41 min speed: 08.36 Cogs cog 12: 00.00% cog 13: 07.69% cog 14: 07.14% cog 15: 06.67% cog 17: 11.76% cog 19: 10.53% cog 21: 09.52% cog 23: 08.70% cog 26: 11.54%