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Discussion Starter · #1 ·
I just got back from a ride and during this outing I knocked my front derailleur out of adjustment somehow. The chain is now rubbing right up against it and making a very annoying sound. How do you adjust the front derailleur so the chain isn't hitting it anymore? I notice there are two screws down there, are those what I need to mess with?

I'm sure this is not needed but here is a pic of what I'm talking about (pic is not my bike). The chain is of course rubbing up against that derailleur.


Appreciate any help.
 

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Braille Riding Instructor
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Did it just pivot at the mount? I've done that a couple of times after taking a big hit in the wrong place. In both cases, I was able to rotate the derailleur back to its original position. You might need to loosen and then re-tighten it, however.
 

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Discussion Starter · #3 ·
Ha, well, I don't really know. I'm not savvy enough with this stuff yet to give you an answer on that. I would take a picture of it but my camera is acting up. All I know is that the right side of the chain is brushing up against the right side of the derailleur, and it's doing it in all gears. I must have done it when I was going down a trail that has a few roots on it at a pretty good speed. I didn't think I was going fast enough to knock anything out of whack though. A bit disappointing.

I looked at where the thing is mounted to the frame of the bike and doesn't look like anything has moved.
 

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Per hdparrish's question/suggestion, if you look at the FD cage from above is it inline w/ the chainrings?

If not, you may need to loosen the clamp that attaches the FD to the seat tube and rotate it so that it is back inline, then re-tighten the clamp.
 

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Snagged7 said:
I just got back from a ride and during this outing I knocked my front derailleur out of adjustment somehow. The chain is now rubbing right up against it and making a very annoying sound. How do you adjust the front derailleur so the chain isn't hitting it anymore? I notice there are two screws down there, are those what I need to mess with?
No, do not fiddle wih the screws, they are limiter screws to limit how far in or outboard your deraileur can move. If it was working OK before, you should not need to mess with those.

Have a look at ParkTools website, they have great how-to guides for tuneups

BTW, I assume it rubs against biggest chainring, while chain is on smaller cogs?

Deraileur can move because of some stuffups in shifting, chainsuck and such. Anyway, as it was suggested already, see if it is aligned with the chainrings and adjust - for that you'd better shift to the smallest chainring to have as little cable tension as possible.
Another thing - if this is a new bike or new cable, than it may be an effect of stretched cable combined with some minor deraileur movement, then some slight cable tension adjustment might help (see ParkTools guide for that as well)
 

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Discussion Starter · #7 ·
Sid Nitzerglobin said:
Per hdparrish's question/suggestion, if you look at the FD cage from above is it inline w/ the chainrings?

If not, you may need to loosen the clamp that attaches the FD to the seat tube and rotate it so that it is back inline, then re-tighten the clamp.
It seems everything is in line. Right now it is in line with the middle sprocket which of course the chain is engaged on.
 

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Discussion Starter · #8 · (Edited)
nampla said:
No, do not fiddle wih the screws, they are limiter screws to limit how far in or outboard your deraileur can move. If it was working OK before, you should not need to mess with those.

Have a look at ParkTools website, they have great how-to guides for tuneups

BTW, I assume it rubs against biggest chainring, while chain is on smaller cogs?

Deraileur can move because of some stuffups in shifting, chainsuck and such. Anyway, as it was suggested already, see if it is aligned with the chainrings and adjust - for that you'd better shift to the smallest chainring to have as little cable tension as possible.
Another thing - if this is a new bike or new cable, than it may be an effect of stretched cable combined with some minor deraileur movement, then some slight cable tension adjustment might help (see ParkTools guide for that as well)
It's a new bike (2011 Trek 4300). I watched a video on adjusting the derailluer but that confuses me even more because he was messing with the screws. Here is the vid I watched:http://www.google.com/url?url=http:...stment&usg=AFQjCNGbT2uP8FDi2Zr25d0eAZbX5JukRg

Ahhhhh, he says he's doing High/Low adjustments. I just watched the vid again.

nampla said:
BTW, I assume it rubs against biggest chainring, while chain is on smaller cogs?
I'm not sure if it does that. I will have to play with it tomorrow to see what is up with it.
 

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Make sure, the derailleur is on right height. When the chain is in the middle ring, the outer cheek of derailleur cage should be 1-2 mm above the teeth of the large ring. Goes without saying, the cage should also be parallel to the rings.
 

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Discussion Starter · #11 · (Edited)
zebrahum said:
See if this helps you:

https://www.parktool.com/blog/repair-help/front-derailleur-adjustments

Your H/L adjustment screws won't have just magically come out of adjustment, this is probably a cable tension adjustment because you have a new bike.
Just from quick read of that link the problem appears to be Front Derailleur Rotational Angle with the "tail too far inward." As seen below in the far left picture.


After reading some of that, it is a bit intimidating. I'll be able to get my hands on the bike around lunch time (two and a half hours for me).

Thanks for the link.

xenon said:
Make sure, the derailleur is on right height. When the chain is in the middle ring, the outer cheek of derailleur cage should be 1-2 mm above the teeth of the large ring. Goes without saying, the cage should also be parallel to the rings.
I'll make sure to check the height of it too.
 

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Discussion Starter · #13 · (Edited)
After looking at it again my problem is for sure the tail being too far inward like in the below pic. The height seems to be fine though. The clamp on the seat post doesn't look like its moved at all. How do I manipulate that derailleur back into alignment?


Sid Nitzerglobin said:
On the upside, assuming you can get it rotated back to parallel and at the correct vertical spacing you should be back to the same shifting behavior w/o any other adjustment necessary.
Yeah, assuming I can fix it. That is a big assumption (ha).
 

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Snagged, from what you've said and from my own experience, my guess is you just need to rotate the derailleur back to parallel. To do this, you will probably need to loosen the clamp, which holds/mounts the derailleur to the seat tube. Just back the clamp screw out a couple of turns, rotate to the desired position, and re-tighten.

Keep in mind, however, that I am not a bike wrench and I'm only guessing because I can't see your bike and judge what is going on. But if my guess is right, it's a very, very simple fix.
 

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Discussion Starter · #15 ·
hdparrish said:
Snagged, from what you've said and from my own experience, my guess is you just need to rotate the derailleur back to parallel. To do this, you will probably need to loosen the clamp, which holds/mounts the derailleur to the seat tube. Just back the clamp screw out a couple of turns, rotate to the desired position, and re-tighten.

Keep in mind, however, that I am not a bike wrench and I'm only guessing because I can't see your bike and judge what is going on. But if my guess is right, it's a very, very simple fix.
Bam! That was it to the T. As soon as I started to losen the clamp I noticed, which I didn't see before, a marking on the tube where the clamp was showing it moved ever so slightly.

I was making this much more complicated than it was. I thought I needed to do all kinds things to get that thing back in line. But no, very simple. Took it for a test spin and went thru the gears, and everything is good to go. Thanks so much for the help, it is greatly appreciated.
 

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Discussion Starter · #17 ·
hdparrish said:
You're welcome. I probably should've been more specific in my initial response. Sure hope you didn't fiddle with your limiter screws. :D
Ha, sure didn't. I was too paranoid I would screw something up if I started to do something I wasn't completely sure of so I just learned as much as possible first.
 
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