12-32 or 11-34 require longer derailleur???
04-30-07 | 08:18 PM
#2
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Originally Posted by wpaul0
Can I use a standard long-cage ultegra or dura ace rear 9 derailleur with a 12-32 or 11-34 casette? Or do I have to go to a mountain bike derailleur (Deore XT) or such?
04-30-07 | 08:19 PM
#3
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12-32 or 11-34 require longer derailleur???
Can I use a standard long-cage ultegra or dura ace rear 9 derailleur with a 12-32 or 11-34 casette? Or do I have to go to a mountain bike derailleur (Deore XT) or such?https://www.bikeforums.net/images/editor/menupop.gif
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04-30-07 | 09:40 PM
#4
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Originally Posted by well biked
Yes, you'll need a mtb RD with anything over a 30t large cog-
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Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
04-30-07 | 09:49 PM
#5
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Originally Posted by cyccommute
I think the limits on long cage road derailers are very conservative. Shimano says that they will only handle a 27 tooth low which happens to be the same limit as a short cage derailer. I know from experience that a short cage will handle more than that (I shoe horned in a 29 once that worked just fine). Before buying a new derailer I'd be tempted to see what you can do with your existing derailer. Changing cassettes is a piece of cake and if it works, you won't have to buy a new derailer. If it doesn't...well you'll be out a few minutes for the experiment
What does the cage length have to do with the large cog capacity? (answer: nothing). I understand that the 27t large cog rating is conservative, but the 30t limit I mentioned is beyond that. 32t and 34t are mtb RD territory-
Last edited by well biked; 04-30-07 at 09:55 PM.
04-30-07 | 09:57 PM
#6
semifreddo amartuerer
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Longer? No. Derailleur with bigger large-cog capacity? Yes.
These properties are not interchangeable. You will most likely need a "MTB" RD, and such a beast will most likely be long-cage. But it is not its long-cagedness that brings about the ability to handle a larger cog; it is the length of the parallelogram.
The RD needs to be able to clear the largest cog, so the pulleys don't rub. If a short-cage "road" (Ultegra/DuraAce) RD doesn't work, than a long-cage road RD won't either.
These properties are not interchangeable. You will most likely need a "MTB" RD, and such a beast will most likely be long-cage. But it is not its long-cagedness that brings about the ability to handle a larger cog; it is the length of the parallelogram.
The RD needs to be able to clear the largest cog, so the pulleys don't rub. If a short-cage "road" (Ultegra/DuraAce) RD doesn't work, than a long-cage road RD won't either.
04-30-07 | 10:32 PM
#7
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Originally Posted by well biked
What does the cage length have to do with the large cog capacity? (answer: nothing). I understand that the 27t large cog rating is conservative, but the 30t limit I mentioned is beyond that. 32t and 34t are mtb RD territory-
If it doesn't work, what is wpaul10 out? A little time.
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Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
04-30-07 | 11:24 PM
#8
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From: Gothenburg, Sweden
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I have an XT long cage RD and even that just barely clears the 34T sprocket on my bike. And only after I gave it a B-angle screw more than twice as long as the original.
05-02-07 | 05:17 AM
#11
russkie
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Originally Posted by ruppster
I have ran a Tiagra RD on a 32 with no ill effects.
