Quote Originally Posted by aicabsolut View Post
I wouldn't put a 32 or 34t cog on the back with a little 30T chainring. A 1:1 ratio of gears (e.g., 30 and 30) means that you get one wheel revolution per revolution of your pedals. This definitely takes little force to accomplish, but you start having to spin like mad to keep enough momentum to keep yourself upright, particularly when gravity is working against you as well. I would most definitely NOT go greater than 1:1 (the 32 or 34 rear cog), because that will mean more than one revolution of the pedals to get a complete revolution of the rear wheel. You just won't be able to go fast enough. I'd advocate sticking with your normal 10sp derailleur and putting something like a 12-27 (shimao or sram) or 12-28 (sram) on the back. That will get you close to a 1:1 and still be pretty easy while allowing you to keep your momentum up such that you don't tip over. If you're running campy, then the current rear derailleur can accommodate a larger cassette (I forget if it's 29 or 32..i think 32), but I still wouldn't go past 1:1.
I have to disagree here. It all depends on where you ride.
When you ride stuff like this regularly, you need little gears. Or at least I do.


Borrowed from DiabloScott

My smallest gear is a 33 - 34. Yes in that order. I ride stuff with long sections of upwards of 12% and some nearing 20%.

Here's what 17% looks like, the Summit Wall.

http://bp3.blogger.com/_hSZo5vjiPmQ/...h/P6140128.JPG

I can climb this at about 4 mph, with my little gears, seated the entire way. I've also been able to stop in the middle of this and start again.

On some other climbs I've seen less than 3 mph on my speedometer. I did not fall over.

For the easier section, North Gate Rd to the Junction I average just under 8 miles an hour and I am not spinning madly. My average cadence is in the high 70s, low 80s. I'd probably go faster with taller gears, but my knees would hate me. Therefore I focus on spinning faster in my easier gears.

Does Aggie_Ama need such low gearing? I don't know. I haven't ridden in the Texas hill country. But low gearing does work and you don't fall over or spin out of control.

V.