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Discussion Starter · #1 ·
I am running a 3x10 with X7 rear derailuer. I noticed last night that when I am in the small chain ring and 9 or 10 the chain rubs at the upper pulley. Is this typical or is the chain too long? I know I am not suppose to be in 1-10, but 1-9 also?
 

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Trail Tire TV on blogger
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Are you saying that the rear derailleur is curling back so far that the lower cog/pulley/jockey wheel is going up behind the the upper?

No this shouldn't happen and is a chain being too long. At least on the normal 9 speed, I've never worked on a 10 speed so I can't say for sure but with my chain at the proper length on the 9 I can't see that 2 extra links(to cover the 2 extra teeth on the 10 speed cassette) being enough to cause that.
to properly size a chain..
take the chain out of both derailleurs, wrap it around the largest rear cog and the largest front ring and add 2 links is the standard for measuring chain length
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right from the SRAM manual...
 

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naa,, it is pretty typical :eek: :D

unfortunately .... can't tell ya how many brand new bikes Ive seem come out of a shop with that issue. :rolleyes: seems to be one of those things that gets over looked at assbly
Well I was thinking he was talking about the chain rubbing the outer frame of the FD cage when cross chained. Completely misread his question.
 

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I am running a 3x10 with X7 rear derailuer. I noticed last night that when I am in the small chain ring and 9 or 10 the chain rubs at the upper pulley. Is this typical or is the chain too long? I know I am not suppose to be in 1-10, but 1-9 also?
Rubs how? Sideways because of misalignment? or is the chain passing itself at the bottom of the upper pulley because the lower one is too high when it rotates back to take up the slack.

The "high lower pulley" issue might be improved with a shorter chain, but be sure that it's long enough to loop the two largest while still allowing some unused cage take up.
 

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Discussion Starter · #9 ·
Here are a couple of pics. It looks to me as there is plenty of extra change but it is full suspension so I am not sure. (The first is when it is 1-9, second is 3-1)
 

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Trail Tire TV on blogger
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yup, chain's too long, do the large - large wrap plus 2 links,(three with the quick clip) but compress the suspension (let air out, put weight on what ever it takes) then measure I'm guessing here but it looks like you need to pull about 4-6 links ..?
 

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Discussion Starter · #11 ·
Thanks. It is still under the 90 day tune up so I may take it to the shop to do, if they will, if not I will do it myself.

How do I determine if I have a long cage derailluer? (sorry noob question)
 

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Trail Tire TV on blogger
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Thanks. It is still under the 90 day tune up so I may take it to the shop to do, if they will, if not I will do it myself.
ya. let them do it. easier :) and honestly they should have done it in the first place. But it is a commonly over looked. Nobody's perfect. ;)
 
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