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Discussion Starter · #1 ·
I read a previous post in which almost every poster seemed to say that a short cage derailleur would handle a 13-29. But, when I did run one a few years back, I seem to recall that there was a rubbing noise when in the 29 (maybe one of the jockey wheels on the cassette?). Anyway, I also seem to recall that there may be a "fix" for that. Can anyone tell me whether there is an adjustment bolt that will angle the derailleur to prevent any issues when in the 29? By the way, I'd be running it with a 36 tooth inner chainring, or maybe a 34 if a I mount that one.
 

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info...

If you read a previous thread on the subject, it should have noted where the "B" screw is now located (since 2001) - under the main pivot. Screw it all the way out, until you feel it disengage, then turn it back in about 1 turn, for maximum clearance.

If that doesn't do it, you're out of luck and a medium cage RD would be the solution. There are no guarantees since all RD hangers are not the same length and frames with the perfect chainstay length can gain up to 3T of wrap over one with the worst case length.
 

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Cage length

ridewt said:
I read a previous post in which almost every poster seemed to say that a short cage derailleur would handle a 13-29. But, when I did run one a few years back, I seem to recall that there was a rubbing noise when in the 29 (maybe one of the jockey wheels on the cassette?). Anyway, I also seem to recall that there may be a "fix" for that. Can anyone tell me whether there is an adjustment bolt that will angle the derailleur to prevent any issues when in the 29? By the way, I'd be running it with a 36 tooth inner chainring, or maybe a 34 if a I mount that one.
Just so you know, the difference between long, medium, and standard cage derailleurs is the position of the bottom pulley, not the top pulley. Hitting the 29t is a function of derailleur body angle (controlled by the "b" screw or equivalent), not of cage length.
 

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I am pretty sure you cant use a short cage without messing with the B screw or having to change the chain length.

For sure, the medium cage works with 12-25 and 13-29 without making any changes to the B setting or chain. I switch these cassettes all the time. Also, I am running a 52-39 up front although I don't think this makes a difference.

For what it's worth. Good luck
 

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What matters, besides RD hanger drop, is 'chain wrap'. This is the total jump in teeth from smallest to biggest on a drive train.

Example:
Cassette 13-29 = 16T difference
Chainrings 53-39 = 14T difference
Add the two together and you get a chain wrap of 30T

I have had good luck with a wrap of 28T using a Campy short cage derailleur.
 

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Works OK for me

I use a 13-29 whenever I go to Europe, for the big mountains. At home I use either 12-25 or 11-23. I swap then around all the time. I've never had a problem and never had to make any adjustments with B screw or barrel adjustors or limit screws. I just change cassettes and it works. I even use the same chain length.
 

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Discussion Starter · #10 ·
Success with the 13-29

I'm the original poster. So I successfully used the 29 with my short cage derailleur. Just adjusted the B limit bolt slightly (actually SRAM race support did if for me) and then the jockey wheel moved away from the 29 and everything was fine. Thanks for your advice.
 

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Campyfan109 said:
I use a 13-29 whenever I go to Europe, for the big mountains. At home I use either 12-25 or 11-23. I swap then around all the time. I've never had a problem and never had to make any adjustments with B screw or barrel adjustors or limit screws. I just change cassettes and it works. I even use the same chain length.
Medium cage derailuer, right?
 
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