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Discussion Starter · #1 ·
I'm trying to tune up my shifting but when I adjust the limit screws the derailer doesn't seem to move much.

I went about this by: shifting up to the biggest cog in the back, smallest in the front, took the the tension off the front derailer, and then went about adjusting the lower limit.

At first I could not get the front derailer to move at all. Then I found if I put a little pressure pushing the derailer out towards the big cog as I tightened the lower limit screw the derailer actually moved. I got this set so the inner plate is .5 mm from the chain ring.

Then I put tension back on the cable. Shifted up to the big cog in the front, and the smallest in the back. Then when I went to adjust the high limit I was again unable to get the derailer to move by adjusting the screw. Does this mean my derailer is shot? Could lubricant fix this? The manual states: "If the amount of looseness in the links is so great that adjustment is not possible, you should replace the derailleur" but I don't know what they're referring to as links.
 

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info..

If you meant to say that you set the inner cage .5mm from the chain, not chain ring, that is correct. The big ring limit screw can also be set with some accuracy before the cable is attached by screw it out and actuating the FD by hand. Regardless, turning the big ring limit screw CCW should allow the cage to move further to the right, IF you have enough cable tension. Increase cable tension and watch for the arm to contact the limit screw. If too much cable tension is applied, you will eventually override the low limit screw and the inner cage will touch the chain in the little ring and largest cog.
 

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Understanding it all

jonah255 said:
Then when I went to adjust the high limit I was again unable to get the derailer to move by adjusting the screw. Does this mean my derailer is shot? Could lubricant fix this? The manual states: "If the amount of looseness in the links is so great that adjustment is not possible, you should replace the derailleur" but I don't know what they're referring to as links.
You may have just hit the limit with the shifter, and so it won't pull any more cable. Shift to the big ring and then pull on the cable that runs along the down tube; you'll probably see the derailleur move farther out at that point, and if you turn the upper limit screw counter clockwise, you can move the cage out farther still. Recognize that you only need the outer derailleur cage to just barely clear the chain when you're in the smallest cog and on the big ring. Not likely the derailleur is shot. Lube is probably not the issue, though it never hurts to put a drop of oil at all the pivot points on the FD.

The manual is talking about play in the mechanism. The various arms of the derailleur are the links to which it refers, and if there's significant slop in the mechanism when you wiggle it by hand, then you may have that problem. Not likely.
 

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Discussion Starter · #4 ·
I got it. I can finally shift to my big cog again! :D

For some reason I seem to have to shift back and forth to get the adjustment of the limit screws to express itself. This is the case with the rear derailer as well. (These are shimano 105 derailers).

Thanks!
 

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Nice front-derailleur. Glad you got it sorted. The real trick is remembering what you did. This will be useful when you, inevitably, have to install another.
 
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