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Chain hitting front derailleur

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Chain hitting front derailleur

Old 12-26-13, 02:30 PM
  #26  
cny-bikeman 
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Originally Posted by gsa103 View Post
That would be typical unless the derailuer has a trim adjustment (essentially a half-click).
No, it's a little difficult due to the continued use of non-standard terms. but if I'm interpreting correctly the OP said it rubs when on the largest crank ring (chainwheel) and smallest sprocket (rear cog?), combo, which is the highest gear, and where one would adjust the outer limit screw, and also rubs when on the smallest chainwheel and largest rear cog, which is where one would adjust the inner limit.

CHSCHEN - would help if you confirmed the above. What you seem to be describing is rubbing when the front and rear are both all the way in and all the way out. If that is true then unscrew (counterclockwise) each limit screw 1/4 turn at a time until there is no rubbing in each of those positions. The highest gear (large front, small rear) may still rub with too much pedal pressure - that's your hint to downshift.
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Old 12-26-13, 05:41 PM
  #27  
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cny you give good advice but I think you have an unfortunate typo here. "rub" not "run?"

Originally Posted by cny-bikeman View Post
It really should not run in those combos, as they are the very ones that one uses to make the front derailleur adjustments. Please make sure brakes are properly adjusted and that everything is properly tightened.
Also I wish this site had a mechanism by which we could rate the quality of posters' advice, so the less experienced would have a basis for deciding whose advice to follow. Although in this thread it seems pretty obvious.
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Old 12-26-13, 06:13 PM
  #28  
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Originally Posted by cranky old road View Post
I think you have an unfortunate typo here. "rub" not "run?"
Thanks much - corrected.
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Please respect others by taking the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!
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Old 12-26-13, 06:55 PM
  #29  
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the poster can grip the deray mount twisting it clockwise from above...that's the click.

for small CR/large cog. relative to cage sides.

but where should the cage be height wise at small CR/large cog ?
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Old 12-26-13, 11:28 PM
  #30  
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Originally Posted by BLYTZPK View Post
the poster can grip the deray mount twisting it clockwise from above...that's the click.

for small CR/large cog. relative to cage sides.

but where should the cage be height wise at small CR/large cog ?
The ft der cage outer plate's lower edge is usually placed 2-3mms above the large ring's teeth when the cage has been pivoted out so the outer plate is just even (as in being away from the frame the same amount) as the large ring is. The cage's height above the other rings is then a result of it's pivot geometry and the rings' tooth counts.

As i tried to explain before, the rotational alignment of the cage is usually that which has the cage's center line parallel with the ring's plane. Some slight rotation either way might be needed for best function over the entire range of the gears but this fine tuning is started with cage and rings being parallel.

I'm not too sure what the first line was about... "deray" and "click". Andy.
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Old 12-27-13, 06:39 AM
  #31  
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Originally Posted by Andrew R Stewart View Post
I'm not too sure what the first line was about... "deray" and "click". Andy.
Originally Posted by BLYTZPK View Post
if you can't read it don't read it
Hard to argue at this point
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If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.

Please respect others by taking the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!
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Old 12-27-13, 12:44 PM
  #32  
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Originally Posted by cny-bikeman View Post
CHSCHEN - would help if you confirmed the above. What you seem to be describing is rubbing when the front and rear are both all the way in and all the way out. If that is true then unscrew (counterclockwise) each limit screw 1/4 turn at a time until there is no rubbing in each of those positions. The highest gear (large front, small rear) may still rub with too much pedal pressure - that's your hint to downshift.
My husband just told me that we apparently adjusted it so that it's not rubbing on the largest chainwheel and smallest rear cog (the highest gear), but it does rub a little on the other side (when the front and rear are both all the way in). We've played with the limit screws so that they're at the very edge of their reaches, and it still unfortunately rubs. We've also adjusted the cord tension so much that we're afraid the cord is going to break at this point. :\
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Old 12-27-13, 02:27 PM
  #33  
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Logic and physics prevail when it comes to mechanical systems. If the cable is too tight the derailleur is never going to reach the inner limit. It's quite easy to see if the bottom of the inner limit screw is being contacted by the derailleur. If not then the cable is too tight. I'd strongly suggest you get some assistance at a shop or co-op.
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There's no such thing as a routine repair.

Don't tell me what "should" be - either it is, it isn't, or do something about it.

If you think I'm being blunt take it as a compliment - if I thought you were too weak to handle the truth or a strong opinion I would not bother.

Please respect others by taking the time to post clearly so we can answer quickly. All lowercase and multiple typos makes for a hard read. Thanks!

Last edited by cny-bikeman; 12-27-13 at 03:02 PM.
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