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I have an 8 inch rear wheel off an adult scooter. It appears to have suffered crush damage - at a guess someone's driven a car over the wheel while on its side.

The bend is smooth and covers perhaps a quarter of the rim on one side only. However there is some crinkling on the outside.

enter image description here enter image description here

And from the side

enter image description here enter image description here

My gut feeling is that this will go badly if I try to straighten it. If it were steel the chance of success would be much higher.

Owner tells me it has never ever been driven over, but they didn't get it new. So its likely been used like this for several years.

Question Is it saveable? either by straightening it, or by leaving it as-is ? Or by bending the rest of the flange inward to match the squashed section?

  • Possibly related to bicycles.stackexchange.com/questions/34201 but that was closed as a rant whereas this is a practical real problem. – Criggie Nov 10 '18 at 1:53
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    Take an adjustable wrench and use it to bend the edge back, more or less straight. I've done this a number of times -- sometimes it works and sometimes not. You do have the danger that the aluminum will "work harden" and crack, but it's worth a shot. – Daniel R Hicks Nov 10 '18 at 3:05
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    Personally I’d ride on it. Scooter wheels are so small and the deck is so low to the ground and you’re standing up anyway, so even if the wheel fails catastrophically, you’re likely not going to be hurt significantly if at all. – RoboKaren Nov 10 '18 at 3:34
  • @RoboKaren I would too, but its not for me. My other half was pulled off a similar scooter by our dog a couple years ago and is still suffering the injuries caused. – Criggie Nov 10 '18 at 4:37
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Result DISMAL FAILURE

I attempted to use a large 12" adjustable spanner to gently tweak the rim back to place. On the first pass along it worked okay, and took out about a third of the offset. It was better but not right.

On the second pass along I felt something crunch. It felt like snapping a thin green twig where the fibres break but don't part. This damage is visible on the left side of this photo. The pressure was no higher than elsewhere, and there was no warning, just a sudden crunch.

enter image description here

Its fairly evident that the rim flange has folded along the weakened line and its now utterly scrap.

Out of interest I gave the other end of the damaged area a good heave and it took about half the elbow effort that the undamaged part required for a similar effect. (bend on undamaged rim is out of shot sorry)

enter image description here

I have salvaged the hub and spokes, tyre tube and tape to rebuild on an undamaged fresh rim, which is why its a bare rim in these photos.

tl;dr aluminium bike parts with visible cracking are utterly unserviceable and unrepairable. Don't waste your time trying to fix bent aluminium parts.

Do recycle them though - Aluminium is infinitely reusable.

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    I wish I'd took pictures of the rim I had the same thing happen to when I tried to straighten out a simple rock ding. It cracked right at the same "base of the sidewall" point. And that was a $80-$100 (US $) DT Swiss rim, too. – Andrew Henle Nov 10 '18 at 14:29
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    Thanks for the followup, was curious to see how this turned out. I've bent out smaller blips with adjustable wrenches every now and then and had it more or less work (the brake surface doesn't usually feel perfect). Finding a tool that could do the same on this kind of damage seemed challenging. – Nathan Knutson Nov 11 '18 at 19:22

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