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Help with carbon safety after crash

I recently crashed my Canyon Grail CF (Carbon). I slipped in a curve and hit a curb with the rear wheel (at about 40km/h). The rear Rim snapped in half, the dérailleur hanger also got cracked but the rest of the bike didn't experience a lot of impact (it landed on the handlebars and the saddle). I have attached a few images showing the damager. There is some on the fork and the handle-bars, I will definitely replace those, but on the frame itself there is nothing, well a tiny scratch but after some close inspection, it seems to quite shallow and only be in the paint layer. I have inspected the frame myself: Cleaning, taking a close look, using the "coin method" (tapping the frame), and also trying to bend the frame to test the stiffness / listen for a crunchy sound. I could not find anything abnormal.

I also got in touch with Canyon for their "Crash Replacement" program. I was told to replace everything (Frame, Fork and Frame), even if there is no damage to be seen, well that answer was to be expected I guess. If I have to replace the frame it doesn't make sense to do it, financially speaking, as I would be pretty close to the price of a brand-new one, which I simply can't afford at the moment.

I'm leaning towards replacing the Fork & Handlebars but keep on using the frame but I wanted to hear other people's opinion on the topic. I know about the risk of internal fractures and delamination but as of right now, Canyon themselves, were the only ones who told me to replace the frame, friends and my local bike shop all said they couldn't guarantee the safety but that the frame is "very likely still good".
I'm a bit unsure about what I should do. I hope someone can help me out a bit.

Thank you in advance!


  • david37david37 Posts: 1,313
    replace the hanger
    ride the bike (with a new wheel obv)
  • Shock is one of the big things that CF materials really don’t like. If it was me, I’d have the frame ultrasound scanned before risking riding it again. That could be difficult at present though. It could be fine, it might be a spectacular failure waiting to happen. I personally wouldn’t risk it without a confirmatory scan, it’s your shout.
  • oxomanoxoman Posts: 11,724
    Personally I'd take it to a carbon specialist for a quick check. Then after that assuming all ok just replace the hanger and wheel. And also be more careful when out riding again. PS happens to everyone.
    Too many bikes according to Mrs O.
  • Thank you for your answers! I thought about getting the frame scanned but couldn't find a good place to do it. I am from Austria and we don't seem to have any Carbon specialists in the country :neutral: . I contacted "" but haven't heard back from them yet. I'll keep you updated about my final decision.
  • me-109me-109 Posts: 1,905
    If it has bent beyond its elastic limits the carbon fibres will shatter noticeably, not leave a hairline crack or sub-surface damage. You don't need ultrasound.

    Or from Google Translate:
    Wenn es sich über seine Elastizitätsgrenzen hinaus gebogen hat, zersplittern die Kohlenstofffasern merklich und hinterlassen keine Haarrisse oder Schäden unter der Oberfläche. Sie brauchen keinen Ultraschall.
  • First.AspectFirst.Aspect Posts: 13,691
    Unless you have genuine concern about a localised impact to the frame, ultrasound or crash replacement seems like an over reaction to me.

    Even the front fork replacement seems a bit much for a scuff.

    Odd that you are fixating on the carbon fibre. Looks to me that the wheel has suffered a cracked weld. You never know about welds - you can't see inside them.
  • edward.sedward.s Posts: 218

    Odd that you are fixating on the carbon fibre. Looks to me that the wheel has suffered a cracked weld. You never know about welds - you can't see inside them.

    It looks like its a pinned joint rather than a weld. The joint has pulled apart on the outside of the bend, exposing the joining pin.

    it must have been a fair old whack to do that kind of damage, hope you survived it better than your wheel!
  • stn5stn5 Posts: 44
    Is your password appended to your username?
  • pinnopinno Posts: 50,539
    edited November 2020
    seanoconn - gruagach craic!
  • I would be worried about the forks or something on a fast descent. I know you shouldn't but as the speed ticks up I always think, what if the forks shattered now. This probably doesn't help.
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