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-   -   Front derailleur won't go in any further (https://www.bikeforums.net/bicycle-mechanics/1034061-front-derailleur-wont-go-any-further.html)

lxmnch 10-10-15 10:54 PM

Front derailleur won't go in any further
 
I have removed the limit screws and the chain is still rubbing up against the inner cage. I have a shimano deore xt and triple crank by sugino. There aren't any BB spacers.

FBinNY 10-10-15 11:28 PM

The first step is to measure the chainline, or distance from the cranks to the frame's centerline. Odds are that it's too small -- the cranks are too close to the frame. Depending on the tyoe of BB and cranks that can be solved either with spacers, or a longer spindle.

Sometimes, especially with fat tube bikes, the chainline is reasonably close to spec, but you still have the problem because the fat tube is setting the FD outboard more. In that case you have two choices, push the crank out with spacers or if it's only a hair off, find what's keeping the FD from moving in more, and file a bit away to allow it more inboard range of motion.

I've used the file method fairly often on modern stuff, but it can only get you so much, and you have to confirm that filing away material that will cause other issues.

thedave80 10-11-15 01:53 AM

I had a similar issue with an older xt front derailleur on my mid 90's Iguana, it would rub on the chain and would shift poorly into the small ring. Recent the derailleur died and I replaced it with an acera front derailleur. I was pleasantly surprised to find that it had more range for adjustment and solved my rub problem. I don't know how similar your problem is to mine but it may be worth looking into.

Lazyass 10-11-15 04:29 AM

Is the cage aligned and did you adjust the limit screws with the cable detached?

Retro Grouch 10-11-15 05:59 AM

Did it ever work right?

If it didn't used to rub you can assume that the components that you have now will work so you have a derailleur adjustment issue. Front derailleurs can sometimes be a PITA to get dialed in. In my experience the problem usually lies in the position of the derailleur on the seatpost - particularly the angle of the cage when viewed from the top.

If it always rubbed you probably have a component issue. If this is on your Long Haul Trucker I doubt it's the derailleur because that has a relatively slim steel seat tube. That leaves BB spindle length. My quick, dirty fix is to install a 2 mm spacer under the right side of the BB.


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