Rear derailer not aligned
10-24-23, 04:45 PM
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Rear derailer not aligned
I have an older giant bike that I use to get around campus. The chain recently came off and bent the rear derailer. I bought a new one as well as a new hanger and installed them but the derailer is still way out of alignment. What would be causing this? I would post a picture but I don’t think I’m allowed to because I’m a new user.
thanks in advance
thanks in advance
10-24-23, 04:52 PM
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If both a brand new rear derailleur ("RD") and a brand new RD hanger are installed on the bike and the RD "is still way out of alignment," i.e., more than a little bit off, then there are two possibilities: (1) the dropout or other part of the frame is also bent; or (2) the new parts are bent. Of the two it seems that the former is more likely if the chain came off hard enough to bend the previous RD.
10-24-23, 08:41 PM
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The RD takes its alignment cues from the hanger. There's no assurance that a newly installed hanger is aligned, meaning that the axis of the bolt is parallel to the wheel's axle. So, unless you used an alignment tool to match the hanger to the wheel, that's still what you need to do.
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Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
10-24-23, 09:35 PM
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A new hanger still requires alignment with the proper tool.
See:
Freewheel derailleur vs. cassette derailleur?
See:
Freewheel derailleur vs. cassette derailleur?
