Different Cassette?

[Veronica]

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.

[Melalvai]

I absolutely love my 22T chainring. It made a world of difference in my life. One mechanic argued for a larger ring in back, and the other told him he didn't know what he was talking about and that I needed the smaller one in front. I know who is the better bike mechanic so now I have a 22T up front!

[aicabsolut]

I know what 17% looks like. I think I hit around 3-3.5mph once on a 22.5% grade. I thought I was going to fall over. I would've liked a granny gear then, but I still think a bigger cog than ring is overkill on a road bike for most people, even those who climb mountains.

[SadieKate]

How old are you, aicabsolut? You obviously race. You look young and thin in that picture. You absolutely don't look like the average rider in power to weight ratio or fitness, and I haven't seen any posts from you about riding centuries or double centuries with loads and loads of long and steep climbing. Just trying to figure out what experience drives your comments.

You think Peter White's experience is wrong?

[OakLeaf]

I thought I was going to fall over.

The thing is, that it's nearly impossible to pedal both smoothly and with a ton of force, especially at a very low cadence. Even many pro riders on TV sway from side to side when they're climbing or sprinting. Touch wood, but so far I've never felt like I was going to fall over on a triple, and I've seen 3 mph plenty of times. I definitely felt like I was going to fall over when I demo'ed a bike with a compact at the retreat when I returned to road riding - and I definitely felt like I was going to fall over the following summer when I took my old race bike (low gear 42x21) up a serious hill around here. (Both times I unclipped and walked before I fell over involuntarily. ) So I think falling over has as much to do with pedaling smoothness as it does with speed. That is, the wheels are producing a certain amount of gyroscopic force, which is fixed for any given speed and wheel; but the rider input is moving the bike side to side by a greater or lesser degree, working against those gyroscopic forces, depending on how smoothly they're pedaling. And that's where shorter gears can help.

If I understand it correctly, MTB wheels are producing a greater amount of gyroscopic force just because the rims and tires are heavier (or technically, they have greater mass)? If that's the case, that would explain the ability to go slower without falling over than one could on a road bike?

(And just for the record, I doubt one could ever walk faster than pedal. Sure we can all easily walk 4 mph on the flats, but up those hills that we're struggling to ride? I don't think so.)

For myself (meaning my present strength level, my terrain, and my lack of commitment to get much stronger in the near future), I'm only talking about putting a 12-27 in place of my current 12-25, or putting a 26T chainring in place of my current 30. Probably the former and almost certainly not both. With my 39T middle ring (which I like and don't want to change), going down to 26 in front would be a pretty big jump.

[Veronica]

Overkill?

I'll keep that in mind on my next double century with more than 13,000 feet of climbing.

Gearing is like saddles. What works for you does not work for everyone else. Labeling it in a derogatory manner makes people who may need that gearing less likely to get it.

V.

[maillotpois]

Ditto what V and SK have said.

I coach people to ride the Death Ride in the Sierras. 130 miles, 15,000 feet of climb at elevation (up to 9000 feet). Sure, not everyone needs a granny gear. But a lot do, and those who do don't spin like mad or fall over or anything. They just spin up the hill. (And save their knees).

If they were racing a course with one or two high gradient "walls", but rollers otherwise, and if they were all as young and skinny as my cyclocross racer boys, then they wouldn't need it. But for the the average endurance cyclist tacking a long endurance pace and length mountain climb a granny gear is anything but overkill.

[jobob]

I still think a bigger cog than ring is overkill on a road bike for most people, even those who climb mountains.

Golly gee, I must be hanging out with the wrong group of people then.



Oh and by the way, one of my bikes and both of my husband's bikes have a 26t front chainring and a 32t rear.

Every few months or so someone has to come on this list and pontificate about how "most people" don't need a triple chainring, don't need a small front ring, don't need a big cassette, and so on.

So please, do point out once again how lame my husband and I are.

[maillotpois]

So please, do point out once again how lame my husband and I are.

Oooh - wait - me first!

Let's see... you see phantom flamingos, eat too much cheese, you probably drive the speed limit, um, you are prone to carousing, ... what else? hmm. anyone?

[jobob]

And I drive a Subaru!

Most people don't need a Subaru.

[SadieKate]

Don't forget she will do anything for beer and ice cream. You don't even have to provide them together.

PS, I like the avatar.

[jobob]

Don't forget she will do anything for beer and ice cream.

Oh, I have my limits. Sort of.

[maillotpois]

Hm. Seems to me that several of us drive subarus...

[Veronica]

Just 'cause I own one doesn't mean I drive it much.

Speaking of cheese... we went to the Cheese Factory to get some lunch last Friday after riding Bolinas Ridge. I like cheese!

V.

[maillotpois]

They also have great little mini cheesecakes there.

Just sayin'.