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Discussion Starter · #1 ·
I got a dumb question on cage lengths and compatibility. First question is can I run a short cage with a 11-32 cass. and a 22/36 chainring combo in the front. My first of many questions is can I run a short cage in the rear without issues and can I cross-chain completely without ripping the der. clean off? I know it is bad for the drivetrain to cross the chain and I don't plan on it often but just in case I do will the short cage be able to handle it? If not I guess I'm going with a mid cage. This is also going on an 8.5" travel suspension frame if it matters. The other question is if a 2006 x.9 der cage will fit an 2006 or 2007 x.0 der? I know this is weird but if that carbon x.0 cage goes I have a couple of x.9 cages to sacrifice. any help would be great, thanks.
 

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I can help ya somewhat here. Sram says the largest rear cog is 34t for the short cage, BUT it's chainwrap capacity is 32t. Whazzat mean? Break out your calculator and thinking cap. It's math time.
Chain wrap is compute by this formula:
(large chainring-smsll chainring)+(Large cog-small cog)= Chain wrap cap. (in this case 32t)
So let's do it up.
(36-22)+(32-11)
14+21=35, so that's a no go on your short cage derailleur, but the medium will work champ. As for the cages, contact the SRAM fellas. They'll be able to nod or shake their heads to that one.
 

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Discussion Starter · #3 ·
Thanks a lot Juan. I love when people bust out formulas on how to figure if something will work or not instead of saying "I've never even tried it but my brothers friends cousins iguana said it will work so it must." Looks like a mid cage for me.
 

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Glad to help, especially if it keeps you from spending some hard earned coin on the wrong part. Can't help ya with the Hone question though..... I'd just say maybe but be cautious about them not having the steel thread inserts in the arms. At least use pedal washers. I heard my friend's mom had no issues with 'em though ;)
 

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While the formula is great, if you pay attention to the gears you use you can get away with smaller/shorter caged derailleurs.

If you do the whole table you'll see what gears you can and can't use.

The stated capacities by Sram/Shimano are under inflated and they're not specifically set through by any equation.

Another thing to consider is chain stretch esp on a downhill / full suspension rig. As the suspension goes through its motions, you'll have chain strech which can cause your derailleur some more stress.

To air on the safe side like mentioned above, the medium cage would be better.

I'm pretty sure you can use those cages.
 

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Discussion Starter · #6 ·
The hone cranks aren't for me...Saints for this guy. And you raise a valid point MTB. The reason I want something that will work in all gear combos is becasue I don't want to have to worry about something like then when riding becasue on accident if I shift one click too far or something and my derailleur gets toasted I'd be pissed. Its one thing to smash it on a rock but its another to break doin something dumb like that
 

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While you may be right, I think it's a heckuva lot easier to follow the manufacturer's recommendations as those are the design parameters of the given component. No guesswork, just facts. Hard Core Science. The chain wrap cap. of the medium cage is 37t so he's well within the range. I just think it's risky (and unneccesarily so) to say things that can lead to damage of a spendy chunk of jewlery. Fact remains that you should be able to shift into all your gears from any of the chainrings, regardless of where the bike is in it's travel, and that's precisely what the chain wrap capacity formula allows.
 

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juancancook said:
While you may be right, I think it's a heckuva lot easier to follow the manufacturer's recommendations as those are the design parameters of the given component. No guesswork, just facts. Hard Core Science. The chain wrap cap. of the medium cage is 37t so he's well within the range. I just think it's risky (and unneccesarily so) to say things that can lead to damage of a spendy chunk of jewlery. Fact remains that you should be able to shift into all your gears from any of the chainrings, regardless of where the bike is in it's travel, and that's precisely what the chain wrap capacity formula allows.
No offense, but giving some the formula and saying "this is your only option" isn't correct either. By telling him "you can use this BUT there is an inherent risk..." you're giving him the option to go that route and know the risks thereof.
 

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Agreed, but...
Eh, this could go back n forth & not come to an agreement. This world isn't one for absolutes, right? I just say follow instructions and useage guidelines BAP when it comes to modern equipment. There's always room for tinkering though, but we as consumers have to accept our roles when tinkering throws a pie in our face. I think THAT we can agree on.
 

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Discussion Starter · #10 ·
Both of you make valid points. i'm not a retared when it comes to bikes and I was as shop wrench for quite a few years too. This is just one of those things I wanted some opinions on and left it at that. I understand there are some tolerences for tinkering and although I really wanted to run a short cage I'm going to run the mid cage to be on the safe side and not have to worry since I've been running a mid cage a similar bike for a season without incident. Thanks for the input for all.
 

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njhcx4xlife said:
Both of you make valid points. i'm not a retared when it comes to bikes and I was as shop wrench for quite a few years too. This is just one of those things I wanted some opinions on and left it at that. I understand there are some tolerences for tinkering and although I really wanted to run a short cage I'm going to run the mid cage to be on the safe side and not have to worry since I've been running a mid cage a similar bike for a season without incident. Thanks for the input for all.
I've been running a mid cage X.0 on a 22/32/44 crankset with a 11-34 cassette for more than a year. Never had a single problem at all with it.
 
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