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Discussion Starter · #1 ·
Hi all, I have a small 2009 epiphany with x9 derailleu and truative stylo crank. WHen I first got the bike the front derailleur was off. I adjusted it and noted that in the granny on the front I could only use the first three big cogs on the back any smaller and it would drag against the derailleur.

So, I just shifted to the middle ring and used that instead. Recently I was at the shop and brought this prblem up and they told me that the problem was the frame design. I have a fuel ex and in the granny can go all the way up (cross chain) and not get any scraping. Just wondering if everybody else has this problem with their small epiphany bikes also.

THanks, Jason
 

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Jason,

All triple chainsets are designed that way. It is not the bike design

With a long cage mech it is possible to set it up to cross the full range of the cassette but it certainly is not ideal.

Its the same the other way to. you are not supposed to be crossing the chain from the big ring at the front to the biggest at the rear. it puts too much stress on the chain and mech.
 

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Discussion Starter · #3 ·
Well, I'm aware of that crossing the chain etc... I just thought it was odd that in the smallest cog on the front I can't use anything but the three biggest gears on the back. I"m not talking about using the smallest in the front and smallest in the back. I didn't have that problem with my Trek.
 

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Obvious question but is the front derailleur parallel to the chainrings? Putting your chain on the large chainring, do you get a similar rub with the smallest three cogs of the cassette? If not, a simple twist on the derailleur around the seat tube might help.
 

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ah I think I might be misunderstanding you.

Just to be clear can we use the numbers. (for my benifit, not being patronising)

An xt cassette is either 11-32 or 11-34

11- 34 9 speed has cogs of 11 13 15 17 20 23 26 30 34

The front 3 are 22 32 44 on most chain sets.

So in the granny at the front (22 tooth) at the back you should be able to use the 34 30 26 without any rubbing on the front mech. If it is rubbing then the mech either needs aligining parallel or the stops need adjusting or the cable tightening slightly.

With a long cage rear mech it is possible that you could set the rear to cross more of the cassette ie the 23 20 but the chain may begin to rub on the front mech. This is all on shimano's web site too.

triple chainsets are always a compromise in this sense, which is one of the reason for some people run double chainsets (and sram are bringing out a 10 speed double) the chain line is better with a double.
 

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Sounds like you may be on your way to a solution, but this comes so close to one of my major pet peeves that I just gotta speak up. You must certainly be using thumb index shifters probably shimano. If you used SRAM grip shifts you would not have this problem because they micro adjust. I have worked on many friends bikes and after 30 years shimano has still not figured out that three positions is not enough adjustment for the front derailleur. SRAM grip shifts have 6 I believe. Of my 4 SRAM grip shift setups NOT A SINGLE ONE HAS THIS PROBLEM. And one is an epiphany. The last three friends shimano gear that I adjusted was impossible to avoid the problem you just mentioned.
I actually asked shimano this question a few years back at the Sea Otter. They had no answer for me. I am still waiting to my knowledge even the 2009 stuff did not micro adjust.
good luck... if you wanna solve this problem throw away your shimano shifters
 

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Discussion Starter · #7 ·
Well, I just avoid using the granny unless it s along steep uphill that I need it for. You'll find this funny but they are sram x9 trigger shifters not grip shifters. I've not had the problem with Shimano on my trek bike. Having used both I like the clicky mechanism and feel of SRAM more than Shimano thoguh they are both still good.

WHo knows anyways. It works well for me still.
 

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This doesn't help your shifting problems, but it is definitely something you should be aware of when setting up a front der on the Epi.

According to SRAM's directions the der should be set up with a maximum of 3mm clearance between the bottom of the outer cage and big chainring. If you follow these directions, you will probably bottom your rear suspension onto the back of the der cage. To check this, deflate your shock and compress the suspension.

taking the gripshift suggestion one step farther, i use an old XT thumbshifter for front shifting duties, primarily for the trim capabilities.
 
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