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Could I have un-bent my aluminum frame?

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Could I have un-bent my aluminum frame?

Old 05-02-21, 01:28 PM
Arthur Peabody
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Could I have un-bent my aluminum frame?

A month ago a motorist drove into it. The firefighters on the block were nice enough to take it in and keep it for me until I could get around to it.
I'm about ready to start riding again, I think. The bumper hit the left crank arm, bending it so much that it hits the chain stay. The string test measured
one side 5 mm further out than the other. The rear dropouts, originally spaced 135mm, were spread to 140. I put a big bolt on it, slowly cranked it down to 126, 2mm/day.
When I remove the bolt now it measures nearly even. If I re-build it, try to ride it, will it break at the weakest spot? Will it wobble? Would holding a heat gun on the stays
for a while help?
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Old 05-02-21, 02:16 PM
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You will need to check the stays often if you decide to keep riding it. Al doesn't do well when bent back and forth. If you are a heavy rider I would check it at least after every 2nd or 3td, ride.
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Old 05-02-21, 02:35 PM
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I would be very skeptical about riding that frame. If you are a big, heavy person, even sketchier. As stated above, aluminum does not withstand the bending well at all. If you look into spreading the stays on a bike, the info you get is to not do that with aluminum, titanium and obviously carbon fiber. The heat gun is a very bad idea. That will definitely weaken the aluminum tubing.
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Old 05-03-21, 07:05 AM
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Warm forming 6xxx and 7xxx is done in industry in controlled conditions but I would be leery of DIY. People ride Al bikes with spread dropouts from 126mm to 130mm all the time, with some success and some failures and that is without any crash damage.
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Old 05-03-21, 08:05 AM
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Old 05-04-21, 05:25 AM
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if the motorist was at fault and had insurance then you’re owed a settlement equal to the actual cash value of your bike.
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