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Enter image description here

I bought it this way without the seller noting the issue, so experience from riding with these is zero. Rims are Ritchey Girder OCRs. The crack is pretty small, but noticeable, and I will be running Maxxis DTHs on it, so I will pretty much load the inner tube with 70-80 psi or maybe even more. The crack runs unto the inside of the rim. The brake surface is still thick and deep and I doubt that it's worn out its lifespan.

I just want to know if I can still use these in the long run without compromising safety. I know a crack on a rim is stating the obvious and if I'm skeptical, it would be smart to just buy a new rim, but I'm in need of a well functioning bike as the pandemic restricts public transportation, and buying a new rim just doesn't fit my budget right now.

If I can repair these, how would I proceed? These rims are too beautiful to let go, and it would be nice if I can do something about it.

I shined a flashlight through the crack and it seems that light does not seep through it, if ever that helps. I will inspect it further to see if the crack I saw from the inside is just from the paint and not the aluminium. By any chance, if it is just a deep surface scratch, will the rim still be usable for a long time or so? If it helps, I won't be using v/u brakes.

Picture of the supposed crack in the inner part of the side wall:

Enter image description here

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    Just to clarify, it sounds like you are saying that it’s not just the brake surface, you can see the crack from inside the rim. I initially thought that was just a surface scratch, but if the crack goes through the entire sidewall, then that rim is indeed dead.
    – Weiwen Ng
    Commented Jul 26, 2020 at 20:04
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    If you purchased a pair of these inspect the other carefully
    – mikes
    Commented Jul 26, 2020 at 20:17
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    Is it really a crack or a deep scratch? The way it thins out makes it look a bit like a scratch. Scratch would be OK. It would be strange for a crack to appear without any other signs of deformation. Scratch could come from the milling process.
    – Michael
    Commented Jul 27, 2020 at 10:06
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    @legaspoiroy try pushing it, hard with your thumbs while your fingers are braced around the rim. It should have no more flex than the good side of the rim. If it flexes worse, then you know its dead. If it doesn't "feel" different, then its still inconclusive.
    – Criggie
    Commented Jul 27, 2020 at 11:03
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    Kudos to the OP for including photos, both to start and to supplement the discussion. That said, it can be hard to take a good one of small details, and I can’t see inside the rim clearly. It is starting to look more like a surface scratch, though.
    – Weiwen Ng
    Commented Jul 27, 2020 at 11:17

2 Answers 2

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Sorry, those rims are trash (or wall art).

I'd chase down the seller and demand your money back, and report them on whatever sites they were advertising on for selling items in a known dangerous state.

The crank may be small now but it will propagate in both directions and get bigger. Cracks on thin section aluminum cannot be welded as the heat will destroy the heat treatment state of the metal around the repair.

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    Concur - there is no paint on the outside braking track. On the inside, there appears to be a white layer of plastic, and I'd suspect the crack is visible there. Here's a gratuitous slow-motion shot of exactly this rim failure, youtube.com/watch?v=KLZaITy5w8I Had he been turning harder, he'd have gone down.
    – Criggie
    Commented Jul 27, 2020 at 2:45
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    Failure modes for such a crack are a) bulging of the flange and locking the wheel in the rim brakes, or b) failure to restrain the tire and immediate blow out of the tube. Either failure mode can turn out deadly if it happens under unlucky circumstances. Commented Jul 27, 2020 at 13:32
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Ultimately - we can't tell you what is safe and what is not. Its your decision in the end whether to ride this rim or recycle it. A replacement rim is cheaper than an accident, even with full cover.

If you ride it, there will always be the nagging thought in your mind "what-if it fails on the next corner?" which will decrease your overall confidence in your bike, limiting your speed and/or enjoyment.

Remember, successful rides don't mean it won't fail in the future.


But I've also had hard choices before, perhaps riding something that should really be replaced.

If you, as a competent adult, choose to ride this rim, then consider these basic precautions:

  • Measure the length, accurately. Use calipers if you can, or a steady hand with a good ruler. Note this measurement down and date it.
  • Inflate your tube/tyre to riding pressure. Then lay your ruler's edge along the flat face, and put a torch/flashlight behind it. Take a photo showing where light might be coming through. Save and date this photo.
  • Repeat these tests regularly. I'd go with weekly, you might choose fortnighly, monthly, or whatever window works for you.
  • Compare the results. If the crack never grows, and never flexes, it may be okay. If the crack lengthens or the sidewall is no longer flat (co-planar!) then immediately stop riding it.
  • If you're out riding and applying the rear brake gives a "pulsing" feel, immediately release the rear brake and stop with the front brake.

If you're on a long ride, I'd check multiple times across the ride too.

UPSHOT Personally I'd replace it cos teeth don't grow back. You have to make your own decision. If you do ride it, minimise risk with vigilance.


Here's a rim on my own bike that failed suddenly today.

enter image description here

There is no sign of a crack beforehand - the rim failed while inflating tyre to around 80-90 PSI, and thankfully not while being ridden. The only warning was a click about half-a-second before it burst. Also fortunate I was using a track/floor pump and was not as close to the rim as a hand pump would have to be.

Here's a close up video of the crack itself. There is no visible darkening or indication of a gradual crack.

https://www.youtube.com/shorts/6Vu1yzpUKTM

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