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Discussion Starter · #1 ·
I have a Kona Dawgma that I recently put a X7 2x crankset on. It was like night and day compared to my old crankset that came with the bike... It had a few problems with the deore components that are on my bike running with the X7(or at least i thought it could be smoother) so Ive ordered a X0 9 speed long cage rear DR and a X9 shifter, KMC X9 SL gold chain, and soon to get a new cassette as well... My question is this... After reading an older mathmatical thread on long, short or medium cage lengths im all paranoid about whether or not i got the right cage length for my set up.... Can anyone tell me if this set up im going to have is going to work well or will i have to go with a different set up?
 

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Huckin' trails
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A long cage will work fine
Yep. It's all about the tooth count of the crank setup. A short cage is designed to normally run on a 0 tooth count, so with a single ring. A medium is for a 10 to 14 tooth count, so about the one of a 22-32 crank or 24-36. The long cage is for a tooth count of up to 24-28, so a 3 ring crank.

It's only to minimize the rd length and chain length needed, so a long cage will do on any setup. Unless you are freaking out on a few extra grams, keep the long cage.

A shorter cage also allow a better clearance for obstacle for the derailleur and minimize chain slap.

David
 

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Huckin' trails
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would you suggest a med over a long for a 2x set up?
Yes, but a long cage will allow you to use a 3x setup if you ever need to.

If you ride in a place where rock gardens and sticks are abundant, a med cage would reduce the risk of damaging your derailleur, but just a little bit.

David
 

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The way I think about it is Short cage for 1x10, medium for 2x10, and long cage for 3x10.

A little edumication:

Tooth capacities are as follows: Shimano long = 45T; medium = 33T SRAM long = 43T; medium = 37T; short = 30T

What that means is take the largest chainring's number of teeth (42 or 44 for a 3x10) and subtract the number of gears on the granny (22 or 24 for a 3x10). Add that to the largest gear on the cassette (32, 34, or 36) and subtract the smallest gear (11 or 12). So, for a 3x10 running 24/32/42 chainrings and an 11-36t cassette, you get (42-24)+(36-11)=48, so you need a long cage (derailleur capacities are usually a little underrated). For a 2x10 running 26/39 rings and an 11-36, you get (39-26)+(36-11)=38, so medium. Likewise for a 1x10, 36-11=25 so short cage works fine.
 

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Huckin' trails
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Yep, good math. But the rule if thumb about length vs number of ring is usually a good reference.

David
 

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Discussion Starter · #8 ·
Im gonna try and exchange the long cage XO i ordered for a medium... its ride-able now, whats a few more days to have the right set up when your paying the cost for these parts...
 

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Im gonna try and exchange the long cage XO i ordered for a medium... its ride-able now, whats a few more days to have the right set up when your paying the cost for these parts...
I just switched my Jekyll carbon from x7 3x10 to a x0 2x10 crank. I tried keeping the x7 front derailleur. I adjusted it so it worked with the 2x10 cranks. I had some issues with it, so I just decided to put the x0 front derailleur and left shifter on. That works great. But, I still have a x7 rear derailleur, that is a long cage. It works ok, but getting more chain slap then I should. And, the chain length is perfect. I thought about buying just the medium cage assembly. But, the price for that is just as much as the entire derailleur. Bottom line, go with the medium cage, you won't regret it. I'm going to order the x0 rear derailleur at some point, with medium cage.
 

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Discussion Starter · #10 ·
I still have a deore front derailleur and deore left shifter.... u can tall a BIG difference with switching them? my bike shop dude said he could make it work and it has so far... except, if I bedal back in my big ring to set my feet for a fast turn, my chain pops off... wonder if the x7 front derailleur would fix that?
 
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