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What gearing for a TT bike?(8 posts)

What gearing for a TT bike?Gall
Jul 3, 2003 6:24 AM
Hello again,

I know that gearing and etc is a personal thing and all but i was wondering what the norm is for a TT bike.

I have the option to use an 11x23, 11x21 with a 52 or a 53 front chaing ring. what gears should I be trying to push in order to be decent at a TT?

Thanks again for your help!

terrain, wind, corners, speed?DougSloan
Jul 3, 2003 6:27 AM
Little hard to tell. I'd say take the tallest gears that allow you to spin at the slowest area of the course. Don't want to spin out on descents or tailwinds. Tight spacing is good. Got to consider terrain, cadence, wind, road surface, corners, speed, etc. How fast will you be going? How fast do you spin?

re: What gearing for a TT bike?brider
Jul 3, 2003 1:03 PM
I've run a 52 up front with 11-21 in the back for most of my TTs (and road races for that matter). Unless you've got some long climbs, you shouldn't need anything smaller.
can you push a bigger gear?Time Trial dot org
Jul 3, 2003 1:46 PM
If you can push it and it is not extremely hilly, and you ride 24+ mph I'd look at Dura Ace Time Trial 54/42 rings with a 12-23 cassette. I never liked the 11, not much use for me. The 23 being your bailout gear on a climb and the 12 for the DH sections. A 21 is an option, but I prefer the 23 even though I rarely use my larger 4 cogs except when climbing.
Didn't someone mention making that signature image a bit smaller?moo2
Jul 3, 2003 4:24 PM
That thing is obscene!
re: What gearing for a TT bike?BryanJL
Jul 4, 2003 12:35 AM

FWIW, I would suggest the 11-21, 12-21, or a 12-23 (Shimano) because those cassettes include a 16 cog, with a straight block from lowest cog up to the 17. This enables more precise fine tuning since you won't skip cogs (i.e. from 15 to 17). The 11-23 doesn't have a 16 cog (at least mine does not).

I suggest using a cassette with a 16 cog because for me, it has been a far better marriage of cadence and power at TT efforts. I have used a 13-25 for just this purpose.

Again, the exact cassette you use should be chosen based on your abilities, terrain, and wind conditions, but I would suggest getting a cassette that includes a 16 cog, and at least trying it out--it will make fine tuning efforts much easier since you won't go from 15 straight to 17.

Good luck,

re: What gearing for a TT bike?LC
Jul 4, 2003 10:03 AM
Don't think that just because the pro's use some huge 55x11 that you will be able to push that with any speed. From what you have available there, I would go 52 and 11-21 for the 16 cog. I usually use a 53 and 12-21 for a flat TT, 53 and 11-25 for a rolling TT, 50 and 13-25 (Not found in stores, my own custom 13,14,15,16,17,19,21,23,25) for a uphill only TT.
It's not the gearing, it's the legs............MR_GRUMPY
Jul 4, 2003 5:10 PM
If you can hold a 27 mph average for a 40K, I'd give you one answer. If you can only hold a 19 mph averege for the same, I'd give another answer.