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gforce
11-25-2014, 07:44 AM
Thinking about changing my gearing and was looking for opinions.

Currently running force 10 shifters, single 40 tooth racerace wide narrow chain ring up front, red short cage RD with 12 -27 cassette. I want to stay with the
single chain ring set up but need some lower gearing. In our last race, we had some muddy steep sections that forced me to run that would have been faster riding with lower gearing.

I am looking to go to a sram force med cage RD (or Rival) with a sram 1070 10 speed 12 -32 cassette. That way I get a little more gearing at the low end. I have never used a medium cage derailleur.

Outside of the weight penalty, anybody see any potential problems with this or have a better solution - thanks.

Gummee
11-25-2014, 07:47 AM
Shifting's gonna be a titch slower, but otherwise...

1 tooth in the back is 3 in the front. If a smaller ring can be found, it may be less $ than going with a new derailleur and cassette. Certainly going to be lighter.

M

redir
11-25-2014, 07:51 AM
I don't see any problem with that at all as far as functionality goes. The weight penalty is minimal. The only problem I see with it is that you could probably run faster or be more efficient running rather then spinning a 40x32. Cyclocrossers tend to push bigger gears especially in mud where a smaller gear is more likely to spin out. When I raced a single ring set up I ran a 43x27 and anything after the 27 I would just get off and run.

But everyone has their own style. It can't hurt to try.

gforce
11-25-2014, 07:58 AM
Crank is 130bcd so lowest wide narrow ring is 40 tooth.
The course had some off camber uphill turns that were slippery
that you couldn't take with any momentum - hence the need to
spin up in a low gear.

nooneline
11-25-2014, 09:03 AM
1 tooth in the back is 3 in the front.

Well, only if you're hovering around a 3:1 tooth ratio. Which is to say, 1 tooth in the back is 3 in the front if you're on, like, a 48:16, but if you're on a 40:19,
then, well, it's closer to 1 tooth in the back is 2 in the front.

It's just ratios.

sandyrs
11-25-2014, 09:26 AM
The setup you're proposing is very popular, and I see no reason to hesitate to use it.

sparky33
11-25-2014, 09:32 AM
you can easily run a 12-30 (Ultegra) cassette with the Red short cage RD that you have already. gearing not quite as low as a 32 but almost.

...though I agree that a 40T x 12-32 would be terrific gear-wise.


Currently running force 10 shifters, single 40 tooth racerace wide narrow chain ring up front, red short cage RD with 12 -27 cassette. I want to stay with the
single chain ring set up but need some lower gearing. In our last race, we had some muddy steep sections that forced me to run that would have been faster riding with lower gearing.

I am looking to go to a sram force med cage RD (or Rival) with a sram 1070 10 speed 12 -32 cassette. That way I get a little more gearing at the low end. I have never used a medium cage derailleur.

gforce
11-25-2014, 10:24 AM
Just put on a 12 - 28 cassette and it seemed to shift fine. Might try getting a 12-30 and see if it shifts well. Thanks for the opinions.

oldpotatoe
11-25-2014, 11:09 AM
Thinking about changing my gearing and was looking for opinions.

Currently running force 10 shifters, single 40 tooth racerace wide narrow chain ring up front, red short cage RD with 12 -27 cassette. I want to stay with the
single chain ring set up but need some lower gearing. In our last race, we had some muddy steep sections that forced me to run that would have been faster riding with lower gearing.

I am looking to go to a sram force med cage RD (or Rival) with a sram 1070 10 speed 12 -32 cassette. That way I get a little more gearing at the low end. I have never used a medium cage derailleur.

Outside of the weight penalty, anybody see any potential problems with this or have a better solution - thanks.

I'd suggest a shimano 11-32 and with a single 40t up front and proper chain length, you don't need a medium cage rear der. Remember longer cages generally mean the ability to have more chain for big-big combo. One ring, no issue.

vav
11-25-2014, 11:31 AM
FWIW I run a Shimano 5700 RD short cage with an 11-32 cassette and 34/46 on the front with no issues. I just picked another 5700 RD here on the forum for $ 20 for a different bike with the idea of running a single ring 39t in the front with a 12-30 cassette, so for around 40-50 bucks you may get the gearing you need with a minimal weight penalty.

Gfi3
11-25-2014, 11:38 AM
I run that exact same setup (40T w/ 12-32) and love it. I can ride just about anything and have never been left wanting more gears. Only improvement I plan to make is to go 11 spd next year on the new bike.

blantonator
11-25-2014, 12:17 PM
wolf tooth has a 38T ring fro 130bcd. I run the same gearing as you and it's too big for me. I'm hoping a 38T will solve my problem.

http://www.wolftoothcycling.com/collections/chainrings/products/130-bcd-cyclocross-chainrings

Mister Donut
11-25-2014, 12:22 PM
It really depends if you mash or spin, if you run or ride...that said, I'll mix it up depending on course, but these days I do 1x for most setups, generally running a 36T with 12/28.

dhalbrook
11-29-2014, 12:50 PM
I've been running 40/11-28 all season and have been pretty happy, though once or twice I've thought a 30 low end would be nice. My worry about 32 is that it would be so low that you'd be at traction limits on anything but a super grippy course.