Full carbon frame, this is at the bottom of the seat tube. The bike has about 5000km and I'm well below the weight limit. Never been in a crash, thrown on the ground etc. and the bike was always kept clean and well maintained. I've only noticed this today as the bike has been stored in my garage for about a year now.

So does this look like a cracked paint (maybe someone bumping into it while it was stored) or could it be something with the carbon itself?

by hobbyhoarder

Share.

14 Comments

  1. That looks a lot like carbon damage to me. Can’t be 100% sure based on picture alone.

  2. VoidHelloWorld on

    I guess it’s time to say goodbye.

    Did you try knocking gently on the area there and have an audio feedback, it sounds different when it’s damaged.
    You can try to smoothly remove the paint off if you are sure it’s damaged and have a closer look. But I guess it’s dead

  3. PapayaAppropriate898 on

    If you lose the manufacturer’s after-sales service, you may have to use X-ray to fully know exactly what it is going on. Hope it’s OK.

  4. It looks like an impact damage: did anybody else have access to your garage? Someone may have dropped it and cause there damage. Stress failures usually look more clean that that (like a straight line), but it could be a stone hit that you’re just noticing now. Anyway, it’s repairable.

  5. ViolinistSmooth2759 on

    I’m going to go against the flow and say it’s paint only. Heavily reinforced area, pretty hard to crack and looks like paint chipping away.

  6. irregular-bananas on

    What’s on the other side? It doesn’t make sense, but it looks like a bolt that is too long is pushing g through.

  7. Stunning-Bike-1498 on

    Easiest way to find out is to
    a) do some tapping with a coin (compare with a known good tube), close to the defect it will sound dull if it is a carbon fiber damage.
    b) carefully strip away the paint with a scalpel for example, to check the structure underneath.
    c) put some firm pressure onto the spot by hand and feel if the structure gives a little or makes some noise under pressure.

  8. Cracked carbon, take it to carbon repair shop and take advice from someone who knows what they are doing. Frame is maybe not toast as said down here 😉

  9. You have to sand back the paint a little to know anything for sure.

    If it’s the carbon then it looks serious, so I hope it’s not!

Leave A Reply