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Discussion Starter · #1 ·
Recently upgraded my crank with a bigger 3rd ring. Now the issue is I can either

A. Set the fd to clear the big ring and then only be able to use 2 gears when in granny ring, any lower tooth gear other than the 2 highest rubs on the horizontal part of the cage that the chain goes over.

B. Set it to be able to use 3-4 gears in granny and not be able to clear the big front ring to shift into it.

So is there a specific FD out there with a lower horizontal cage support or is there a way to modify my current one? I have tried both the stock shimano altus and another shimano I picked up for $40 off price point (id have to go look to see the exact model) with the same results. Before anyone asks yes its probably a weird crank combo, but I was trying to accomodate 2 different riding types without having to swap parts. I really only use the 3rd ring on xc days and only use granny/middle on trail days. The idea is I wanted a single crank that would do both and not have to swap out. And now in order to do both I have to readjust the FD for each riding situation.

I know I can make a tail extension, but I was hoping to find a FD that doesn't need to be modified...
 

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Doesntplaywellwithmorons!
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Ok, what exactly are the chainrings... any shimano front mtb derailleur should be able to handle at least a 22T difference between inner and outer, and many can do 24T or even 26T.
 

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jahkneefive said:
Recently upgraded my crank with a bigger 3rd ring. Now the issue is I can either

A. Set the fd to clear the big ring and then only be able to use 2 gears when in granny ring, any lower tooth gear other than the 2 highest rubs on the horizontal part of the cage that the chain goes over.

B. Set it to be able to use 3-4 gears in granny and not be able to clear the big front ring to shift into it.

So is there a specific FD out there with a lower horizontal cage support or is there a way to modify my current one? I have tried both the stock shimano altus and another shimano I picked up for $40 off price point (id have to go look to see the exact model) with the same results. Before anyone asks yes its probably a weird crank combo, but I was trying to accomodate 2 different riding types without having to swap parts. I really only use the 3rd ring on xc days and only use granny/middle on trail days. The idea is I wanted a single crank that would do both and not have to swap out. And now in order to do both I have to readjust the FD for each riding situation.

I know I can make a tail extension, but I was hoping to find a FD that doesn't need to be modified...
I run a 46 tooth chainring.....There are several types designed for that type of operation, last years XT, maybe this years...

There are the older XTR's I think 2004 is what I have...

And there are the older XTRs with the moving chainplates

I went from a 44-32-22, 11-32 to a 46-32-22, 11-34. I have a 2004??XTR FD, and a 2007 XTR RD...

When in 22-34, the chain rubs the FD, I can and do run 48-34 without a problem.

Next I want a 48 big ring, I might have to go to a 24 little ring to make it all work, we shall see.
 

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Discussion Starter · #5 ·
I went from a 42, which ran fine, to a 44. So not by any means a giant crank or anything. I can get into 22-34, it just rubs. With the 42 I could run 4 cogs in granny and pretty much everything in middle chain ring. With the 44 I only get 2 good cogs(and a noisey rubbing 3rd) in granny, and I loose 2 (same thing with rubbing) out of the center chainring range.
 

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kramnnim said:
48-34 (do you mean 46?) would be "crosschaining", which is usually not recommended...
Yup I meant 46 tooth, I will go to 48 when this chainring wears out.

Yes it is cross chaining, and I do it, in certain situations...

The thing is you should set it up so if you shift there the RD does not get ruined....

That means on the little to little combo you will have some chain rub but nothing breaks...

I never use little little unless I have forgotten where I am with shifting....

My shifters don't have indicators.
 
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