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Since this seems somewhat related, is the same method of determining chain length for a hardtail the same for a softtail, i.e., chain around big chainring/big cog, no derailleur jockey wheels, with one full chainlink (2 straight sections, 3 pivot sections) of overlap? I'm trying to size a chain for a FS bike, which is my first. I've always followed that rule for my hardtail with good results. I guess I assume the distance gets shorter under compression of the rear suspension...
 

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geogecko said:
Since this seems somewhat related, is the same method of determining chain length for a hardtail the same for a softtail... I guess I assume the distance gets shorter under compression of the rear suspension...
The method is the same. Your assumption is wrong however; a lot of suspension designs lengthen the chain when compressed. The proper way to size the chain would be to let all the air out of the shock (if it's air-sprung) or better yet, remove the shock from the frame, and cycle the suspension through its travel. Find where the chain growth is greatest and size the chain at that point in the travel (with the 2-link rule).
 

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Ahh, you were right. I see a two link increase in chain length needed for my setup.

I do have a problem. I sized the chain for the 2 link overlap, then the 2 extra links for the full suspension "growth," then installed a PowerLink, which adds one more link. So total, I have 5 links of overlap, and in the small chainring, next to smallest cog, I have sag in the chain when it is run through the derailleur. So, I'll have even more when I go to the smallest cog.

Problem is, I can't just remove one link, and still use the PowerLink, I would have to remove two links.

The setup is a 44/32/22 crank, with an 11-34 in the back. I'm using a Shimano XTR SGS derailleur.

Should I just remove two links?
 

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geogecko said:
Should I just remove two links?
You'll probably be okay removing 2 links. You'd only be 1 link short of what Shimano recommends. You'd have to be in big/big, and then sink deeply into travel, before you (might) have a problem.
 

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Thanks, that worked perfectly. After doing that, I cycle the suspension, and it still seems to be about right...I doubt I'll find myself in big/big anyway.
 

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very usefull thread..
i run an xt crank with 27 instead of 22 and 42 in the middle and 12 34 cassette
now i have an xtr 960 rear der long cage and i'm going to change it with an xtr shadow..
should i run a gs version?
i know that the shadow has a longer cage than older xtr..
 

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Almost everything I've seen in the forums here has suggested to get the XT shadow rear derailleur, instead of the XTR shadow. The XTR almost doubles in price, and the only difference is the carbon cage, and 2 out of the 2 jockey wheels have bearings, instead of 1 bearing and 1 bushing. Of course, this comes from someone that has the XTR version, and the second ride already got scratches all over the carbon cage, and I didn't even realize I had hit it on anything... Just an observation, didn't really help you with your question.
 

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short cage

HEllo

Firstly thanks to Speedub your information was great but i still have a little bit of doubt as to what im doing.

I recently bought a Shimano LX M580 GS raqpid rise on the internet. I admit i think i may have made a mistake with the length of the cage but i thought the super long cage was going to be too long therefore touch the rocks andstuff that i passed.

When it arrived it seems very short alot shorter than i ever expected.
I am running a 44-32-22 fromt cogs and a 11-34 rear cassette. I understand the system with the gear combinations but will this cage be ok for the set up that i have. will it still perform the same job or should i pay the extra and return it for the longer cage.

Second Question can i dismount the cage and fit the old cage as its still fine and straight.

Thanks to all in advance look forward to a response.
 

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nig202 said:
I recently bought a Shimano LX M580 GS raqpid rise on the internet.

I am running a 44-32-22 fromt cogs and a 11-34 rear cassette...should i pay the extra and return it for the longer cage.

Second Question can i dismount the cage and fit the old cage as its still fine and straight.
The GS cage will work for your gear combination, but will it work for you? If you're willing to observe the limits I wrote about in the original post in this thread, then mount it and run it. If you feel as though you're going to be forgetful or lax and will frequently shift to the small small combo, expect a lot of dropped chains.

I don't know the answer to your second question. If they're both the same model, the you ought to be able to swap cages with very little hassle.
 

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heckler small 08 setup, is this poss?

ok can this be done? I have a sram x9 short cage rear mech, 11-34 cassette & 22t,34t,bash setup. when the gears are set to big big there is not enough chain length as the rear shocks travel only goes to about half way & is really tight. I havent rode this like this yet, my local bike shop set this up for me but I dont think they checked to see if the rear suspension was fully compressed when they checked the chain length. So is it a matter of just putting a longer chain on or do I need to change the cassette?
 

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mrback said:
ok can this be done? I have a sram x9 short cage rear mech, 11-34 cassette & 22t,34t,bash setup. when the gears are set to big big there is not enough chain length as the rear shocks travel only goes to about half way & is really tight. I havent rode this like this yet, my local bike shop set this up for me but I dont think they checked to see if the rear suspension was fully compressed when they checked the chain length. So is it a matter of just putting a longer chain on or do I need to change the cassette?
Measure & add chain as discussed. Aside from the chain length problem, your setup is beyond the short cage capacity, according to Nate's table..
 

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First off, thanks a ton for this thread Nate. Very informative.

I'd like to go to a 32/22 with an 11/32 cogset short cage. You've mentioned wiggle room in the sizing... I'm right on the cusp I believe.

Will I be able to get away with this setup on a SRAM X0 Short Cage (30T I believe)?

Thanks again
 

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ReductiMat said:
First off, thanks a ton for this thread Nate. Very informative.

I'd like to go to a 32/22 with an 11/32 cogset short cage. You've mentioned wiggle room in the sizing... I'm right on the cusp I believe.

Will I be able to get away with this setup on a SRAM X0 Short Cage (30T I believe)?

Thanks again
Asumming the cages are the same size, I have a short cage X-9 with an 11-34 cassette and 22/32 up front and I can even hit the 22:11 combo (no that I ever do).
 

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kapusta said:
Asumming the cages are the same size, I have a short cage X-9 with an 11-34 cassette and 22/32 up front and I can even hit the 22:11 combo (no that I ever do).
Excellent, thanks!

Did you size your chain along the lines of "Big to Big + 2 links"?
 

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ReductiMat said:
Excellent, thanks!

Did you size your chain along the lines of "Big to Big + 2 links"?
Yes. (Big-Big being 32:34)
 

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wow great thread. (even if it is a bit old, it still applies)
getting ready to convert my 3x9 to a 2x9 and was wondering if I could get rid of some chain slap by shortening the chain and getting a Med cage.. thanks for the advice!!!

slightly off topic.. if I shorten the chain, get a Med Cage, replace 44 ring with a bash guard, should I reset/ move my Bottom Bracket and/or crank outward to re-center it on the rear cassette?

and....
does someone make something like a 24 tooth inner ring for the Stylos crank? the 22 is just a bit to granny even for me. I know all about the math of having all the gears/ratios and you can get just about any combo.. but shifting down the front and up the rear all at once is just a pain.
 

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thomllama said:
wow great thread. (even if it is a bit old, it still applies)
getting ready to convert my 3x9 to a 2x9 and was wondering if I could get rid of some chain slap by shortening the chain and getting a Med cage.. thanks for the advice!!!

slightly off topic.. if I shorten the chain, get a Med Cage, replace 44 ring with a bash guard, should I reset/ move my Bottom Bracket and/or crank outward to re-center it on the rear cassette?

and....
does someone make something like a 24 tooth inner ring for the Stylos crank? the 22 is just a bit to granny even for me. I know all about the math of having all the gears/ratios and you can get just about any combo.. but shifting down the front and up the rear all at once is just a pain.
Yes, shorten the chain. The same rule applies for chain length (big/big + 2) only now your "middle" ring is the big ring. This is the biggest thing you can do in regards to chain slap.

Yes, you can get away with a med cage, I would go with a short even if it means losing the small/small combo which you really should not be using anyway. A med or short cage will help a little bit in terms of slap, but not nearly as much as the shorter chain. In any event, you can still use your current der and see how it goes.

As far as the chainline, I would leave it where it is. It is already set up so that the middle ring is good for the whole cassette. The way I use it, the granny is only used for the 3 biggest cogs and is only used in the most steep/long climbs. Some rides I don't ever use it. Therefore, it is important to me that the middle is in the optimum position (besides, only using the biggest three cogs in granny means that I don't want to move it farther out, either)

There are countless 24t granny ring options available for your crank. You may also want to consider going with a bigger "middle ring". 24/36 is a pretty popular 2 ring combo.
 
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