Why did my rear derailluer brake off (as well as hanger) and go into my spokes?
03-23-09, 07:36 PM
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Why did my rear derailluer brake off (as well as hanger) and go into my spokes?
I am a good bike mechanic. Chain length and indexing were perfect (chain was not too short and limit screws were set right). I was in the small chainring and 23 tooth cog on a 9 speed 12-26. I was going up hill and rode over some twigs and leaves and then all hell broke loose. The rear derailleur snapped off the hanger and I had to walk it home. Anyone have any ideas of what could have caused this?
03-23-09, 07:47 PM
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might have been a branch that was thrown up and kicked into the spokes.
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Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
03-23-09, 08:09 PM
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My hanger failed in similar manor.
I am assuming the hanger is aluminum. Aluminum doesn't take well to rough treatment the way steel does -- that is, it doesn't bend like steel, it tends to crack but often imperceptibly.
Therefore, its possible that at some point in the past you had a fall or the bike fell over or the hanger was some other way damaged enough to create a hairline crack in the aluminum. In such cases the the hanger will fail eventually but until it does you won't know its damaged because the damage is such that you can't readily see it.
I am assuming the hanger is aluminum. Aluminum doesn't take well to rough treatment the way steel does -- that is, it doesn't bend like steel, it tends to crack but often imperceptibly.
Therefore, its possible that at some point in the past you had a fall or the bike fell over or the hanger was some other way damaged enough to create a hairline crack in the aluminum. In such cases the the hanger will fail eventually but until it does you won't know its damaged because the damage is such that you can't readily see it.
03-23-09, 10:09 PM
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Most likely, you got a stick kicked up into the chain and bottom pulley and you kept pedaling. The chain jams up and you rip off the derailleur.
No worries, it happens all the time. Get a replacement hanger. If the derailleur looks trashed, you can usually bend back the cage. I ripped off my XTR derailleur on the second ride.
No worries, it happens all the time. Get a replacement hanger. If the derailleur looks trashed, you can usually bend back the cage. I ripped off my XTR derailleur on the second ride.
03-24-09, 12:32 AM
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Yeah that is what probably happened. I just tried to reuse the chain on another bike and it is good no more. Instead of stretched it is twisted, warped.
03-24-09, 11:00 AM
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cazzooo - if you're in the market for a good RD at an excellent price:
https://www.cambriabike.com/shopexd.a...EAR+DERAILLEUR
https://www.cambriabike.com/shopexd.a...EAR+DERAILLEUR
