39 x 25T
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Does anyone use this chainring and cassette combo?
I found it difficult to climb when grades exceed 12%, maybe it's a technique thing, the grade pitches up to 16% and it was pure torture. I was going so slow and was fairly sure it went faster with a compact.
I found it difficult to climb when grades exceed 12%, maybe it's a technique thing, the grade pitches up to 16% and it was pure torture. I was going so slow and was fairly sure it went faster with a compact.
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16% on that sounds like torture indeed. Around here most people are running 34x27 to cope with those gradients up to 20%. Also it's nice to spin uphill, at least in training
Bikes: Raw Ti, 650b flatbar CX
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A. You need some fitness build up so get fit on the 10% or less grades first
B. Here is a gear calculator to help you determine the best gear vs rpm vs speed http://www.gear-calculator.com/#
C. Good luck!
B. Here is a gear calculator to help you determine the best gear vs rpm vs speed http://www.gear-calculator.com/#
C. Good luck!
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I run 39x23.
Slam your stem.
PoorCyclist wrote:Does anyone use this chainring and cassette combo?
I found it difficult to climb when grades exceed 12%, maybe it's a technique thing, the grade pitches up to 16% and it was pure torture. I was going so slow and was fairly sure it went faster with a compact.
It's not technique, it's just a big gear. I use a 39x25 in an area with quite a few climbs peaking at 20 - 25%, loads peaking at +15% and a few that average 10%+. Quite frankly though, it's not big and it's not clever, it just makes it a damn sight harder and slower overall than it should be! I can't be bothered to spend any more on this one, but my next bike will have different ratios.
We are lucky to have a lot of big and/or steep climbs in California. Get a compact if you want to enjoy them. You can shift to a higher gear if it doesn't hurt enough.
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You will be able to climb faster with less fatique using proper climbing gears. Using to steep a gear will just kill your legs. I have a road I climb several times a year, after a increasing grade for the first five miles you hit a sustained grade of 20 percent for two miles with it hitting 24 percent for about a half mile of that and the piss poor road surface just makes it harder. I have done it with a 39x25 and frankly it killed me. My best time was with a 34x29 and I had the legs to climb over the pass three more times that day (118 miles total miles that day). I have found a 12x29 with a 52x36 chainring a great choice for most big climb days. On flats or rollers I do like a 11x23 with a 52x36, not bad but I need to be able to spin a bit faster in a sprint. Look at the gearing in the Giro mountain stages, climbing gears rule!
WW Velocipedist Gargantuan
rustychain wrote:You will be able to climb faster with less fatique using proper climbing gears. Using to steep a gear will just kill your legs. I have a road I climb several times a year, after a increasing grade for the first five miles you hit a sustained grade of 20 percent for two miles with it hitting 24 percent for about a half mile of that and the piss poor road surface just makes it harder. I have done it with a 39x25 and frankly it killed me. My best time was with a 34x29 and I had the legs to climb over the pass three more times that day (118 miles total miles that day). I have found a 12x29 with a 52x36 chainring a great choice for most big climb days. On flats or rollers I do like a 11x23 with a 52x36, not bad but I need to be able to spin a bit faster in a sprint. Look at the gearing in the Giro mountain stages, climbing gears rule!
Thanks for that; nothing like 24% round my neck of the woods sadly, but nice also to know that the 29 can cope if ever called upon.
Just a small reality check.
Here is how Pros ride up Angliru, where the steepest 6 km (less than 4 miles) average a whooping 13,1%:
http://www.youtube.com/watch?v=ulViOm2P ... ure=relmfu
And gearing they used:
Juanjo Cobo rode 34×32
Nibali 34×29
Kessiakoff 34×28
Fuglsang and Mollema 36×28
Bradley Wiggins and Chris Froome 38×32 asymmetrical front chain
Of course our own WW members, who regularly conquer multi-mile 20% climbs, would have flown up that Spanish hill...
Here is how Pros ride up Angliru, where the steepest 6 km (less than 4 miles) average a whooping 13,1%:
http://www.youtube.com/watch?v=ulViOm2P ... ure=relmfu
And gearing they used:
Juanjo Cobo rode 34×32
Nibali 34×29
Kessiakoff 34×28
Fuglsang and Mollema 36×28
Bradley Wiggins and Chris Froome 38×32 asymmetrical front chain
Of course our own WW members, who regularly conquer multi-mile 20% climbs, would have flown up that Spanish hill...
rustychain wrote:I have a road I climb several times a year, after a increasing grade for the first five miles you hit a sustained grade of 20 percent for two miles with it hitting 24 percent for about a half mile of that and the piss poor road surface just makes it harder.
What is the total elevation gain of the climb, and can you post a graph from one of the mapping sites?
For comparison, this is Monte Zoncolan.
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Some interesting roads here I found,
http://www.toughascent.com/blog/?p=224
It's no Zoncolan but I felt a little out of breath as I scrolled down the page,
I would like to try (not on the Standard though!!!) but I just don't want to descent it, would like a "team" car to SAG me down after the climb.
http://www.toughascent.com/blog/?p=224
It's no Zoncolan but I felt a little out of breath as I scrolled down the page,
I would like to try (not on the Standard though!!!) but I just don't want to descent it, would like a "team" car to SAG me down after the climb.