's Forum Archives - General

Archive Home >> General(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 )

gearing question!(10 posts)

gearing question!Grinder
Jul 18, 2001 8:07 AM
My last bike as a 12 speeder. My new one has 3 chain rings and 24 speeds.

What I'd like to do (just for shits and giggles) is to make a little diagram on what gears to use - smallest to largest.

Is there an easy mathematical way to do this. I think there is but I'm having brain cramps at the moment
re: gearing answerSpoke Wrench
Jul 18, 2001 8:22 AM
gear inches = chainring teeth divided by cassette teeth X 27.

Work out that equation for every gear combination and you can plot your gear ratios in sequence.
Phun w/#sgrzy mnky
Jul 18, 2001 8:28 AM
Make up a little matrix - put the front combos on one side of a box and put the rear combos on an adjacent side. Now fill in the combos.
Bonus knerd points - print it out on your PC and tape to your stem for quick reference! Impress your buds....
better idea for nerd points.Grinder
Jul 18, 2001 9:09 AM
enter it onto a palm pilot that's attached to your stem.
Another idea for nerd points.jagiger
Jul 19, 2001 5:21 AM
...tape the list to your helmet and wear big thick black rimed
glasses (ala Buddy Holly, Elvis Costello, et al).....
Or, go to Sheldon Browns siteMel Erickson
Jul 18, 2001 8:34 AM
and use his gear ratio calculator.
re: gearing question!Len J
Jul 18, 2001 8:41 AM
Try this site:

select the gearing table yu want & then answer the questions, recalculate & I think you will have what you need.
front divided by rear times wheel diameterclub
Jul 19, 2001 5:18 AM
like 52/13 times 27 = 108
then multiply by Pi for travel per pedal revolution
a little chart on the stem might look geeky but it is a great way to memorize your gears. I can still recite the gear-inches of my 12-sp. straight block race bike, 20 years later.
what are gears?dale c
Jul 19, 2001 5:35 AM
I am new to biking, and I sometimes wish it were easier to peddle, especially when goin uphill. Do some bikes have different gears? I am riding a new Trek 1000. Thanks for any help.
yeah i made a tablebike_rider81
Jul 19, 2001 6:39 AM
i have been soo bored at work that i made a table i excel. it is something to play around with and since you have excel on your screen it lookes like you are actually doing something. i found out something interesting: the triple setup(52/42/30 11-32) that a coworker uses has a bigger gear range in its big ring than i have altogether(52/39 11-23). and i see triples set up like that all the time at my shop. but i shouldn't talk too much b/c i have yet to take a road bike into the mountains. but i just bought a 5900 and am dieing to do so. i think i will be hurting pretty bad, but i am young