Rim Size Cadence:  to:  by:
Tire Size: Chainrings:
Cogs:
How fast will I be going at 80-100 rpm in these gears?
 Cadence Gear  80 90 100 Cadence   Gear
39x11 35.76 40.23 44.70 39x11
39x12 32.74 36.83 40.92 39x12
39x13 30.22 34.00 37.77 39x13
39x25 15.71 17.68 19.64 39x25
39x29 13.50 15.19 16.87 39x29
50x11 45.83 51.56 57.29 50x11
50x12 42.01 47.26 52.51 50x12
50x13 38.78 43.63 48.48 50x13
50x25 20.15 22.66 25.18 50x25
50x29 17.33 19.49 21.66 50x29
53x11 48.55 54.62 60.69 53x11
53x12 44.52 50.09 55.65 53x12
53x13 41.10 46.24 51.37 53x13
53x25 21.36 24.02 26.69 53x25
53x29 18.43 20.74 23.04 53x29
Colors group similar values. 20+ is green, 10ish-20, blue, and below 10, red.