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Old 09-08-09, 10:57 AM   #1
rupes
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Slightly bent frame?

I think my bike may have been knocked or have fallen over recently and now I'm having a few problems with it. The back wheel runs true but is a lot closer to the left of the frame compared with the right. This has caused the brakes to rub a lot on the left side. I've tried adjusting the brake balance screws but even with the left screw (from back of bike) wound all the way in, the brake pad still rubs a little. The gears don't work as well as they used to either. They change from low to high fine but going back from high to low is really bad. Doesn't quite make the change and rubs against the next cog.

I've tried re-seating the wheel but the situation is exactly the same which makes me think that maybe one of the hangers is bent or perhaps the frame going from the seat post to the wheel is bent slightly. There's nothing obvious though. Is a bent frame the most likely cause? Any help much appreciated.

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Old 09-08-09, 11:36 AM   #2
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My first thought was that the axle is not seated, but you've checked that.
Is it possible that the brake(s) has been knocked out of position?
Is it possible that the derailleur hanger was bent?
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Old 09-08-09, 11:51 AM   #3
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Thanks for your reply.

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Originally Posted by Al1943 View Post
Is it possible that the brake(s) has been knocked out of position?
There's no sign of the brakes being knocked so I would assume no.

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Is it possible that the derailleur hanger was bent?
I've taken a picture and it looks like the bottom of the frame might be a little bent.



It looks like just the bit the derailleur attaches to is bent so I don't see how it would affect the distances between the wheel and frame. Bending it back might fix the gear problems though.
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Old 09-08-09, 11:56 AM   #4
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Dropout and derailer hanger both look bent.
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Old 09-08-09, 12:02 PM   #5
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Dropout and derailer hanger both look bent.
Would it be best to bend the dropout back into place and buy a new derailleur. I've heard you can get new hangers but a new Shimano derailleur is so cheap it hardly seems worth it.

Would bending the dropout back do anything to correct the alignment of the wheel?
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Old 09-08-09, 12:29 PM   #6
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Would it be best to bend the dropout back into place and buy a new derailleur. I've heard you can get new hangers but a new Shimano derailleur is so cheap it hardly seems worth it.

Would bending the dropout back do anything to correct the alignment of the wheel?
Don't take this too personally, but being an X-mart bike the alignment may not have been right to begin with. That being said, straightening the dropout may help the wheel alignment. It's definitely bent. You shouldn't need to buy a new derailleur unless it's actually been damaged itself.
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Old 09-08-09, 02:50 PM   #7
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Managed to straighten the dropout but it doesn't seem to have helped any of the problems. Going to take the bike down to a LBS tomorrow and have them look at it.

Thanks for your help though guys.

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Don't take this too personally, but being an X-mart bike the alignment may not have been right to begin with.
It's a Raleigh bike but a pretty low range one so you may be right.
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