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Should I be worried
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I noticed this crack today after my trainer ride. Not sure how long it has been there. Should I be worried and have it looked at? Is this normal?


Last edited by: bjklemmer: Apr 2, 20 17:24
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Re: Should I be worried [bjklemmer] [ In reply to ]
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Where is it on the bike? Does it sound dampened when you tap it with a coin?

Strava
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Re: Should I be worried [gmh39] [ In reply to ]
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I would definitely be worried given it appears that's the seat tube? It the frame was to fail at that point it would result in a very nasty accident. It might only be superficial but I wouldn't ride it without having it verified as safe first.
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Re: Should I be worried [gmh39] [ In reply to ]
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Looks like it is under the seat post. I think that design doesn’t have a conventional seat tube. The seat post is only supported by the seat stays. Unfortunately, it looks cracked at the load bearing junction, but I could be wrong.
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Re: Should I be worried [TurtleMan77] [ In reply to ]
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Yup, looks like the crack is where the chainstays join the "seat tube" (definitely on the load path). Get it looked at.



ECMGN Therapy Silicon Valley:
Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)
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Re: Should I be worried [bjklemmer] [ In reply to ]
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That does not look good.

Take the seat post out and in a dark room put a light down in the seat tube as near the crack as possible. Then carefully inspect the potentially damage area for spider cracks. Carbon doesn't generally brake in a straight line but paint can do a good job of hiding the full extent of the issue.

An inherent design limitations of the frame shape is that you have to be very careful about seat post insertion depth. The set post can't go very deep as there is no seat tube and it will damage the seat stays if it bottoms out. However if not enough seat post is inserted you localize stress and risk damage specifically when transporting the bike. Side ways forces on the seat which happen if the bike falls over or is knocked around during transport are amplified by the leverage of the seat post and aren't then dissipated over much area. The way carbon fails means damage caused in transport wont necessarily show up immediately. What you may be looking at is a crack in the paint caused by a more serious structural issue with the frame. Or it could just be a crack in the paint. I would not however ride it outside until it was verified by a professional.
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Re: Should I be worried [bjklemmer] [ In reply to ]
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I guess there are professional ways to inspect the carbon without removing any paint. Would probably cost something and is maybe not 100% sure.


That said, a way to inspect the carbon yourself is to sand away the paint at the crack. Although a sanded surface part is ugly, a crack is ugly too.
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Re: Should I be worried [longtrousers] [ In reply to ]
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yep, someone who knows what they are doing with carbon can inspect a frame without removing the paint. My wife had an accident a couple of years ago and we had the frame professionally inspected. I can't remember the details but it involved iridescent dye and some scanning equipment. I think I payed around AUD$100 but would depend on who you deal with. I would definitely get it inspected properly.
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Re: Should I be worried [bjklemmer] [ In reply to ]
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Hey, your seat tube may have been too long and jammed to the bottom and pushed on the carbon and cracked it. This is something they give as instruction with the Kestrel Airfoil Pro.

I had one of these bikes and loved it in many ways but its reach was a tad long for me.
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Re: Should I be worried [bjklemmer] [ In reply to ]
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I'd buy a new frame.
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Re: Should I be worried [bjklemmer] [ In reply to ]
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I have the same frame. I don't ride it on the trainer b/c I was worried that might happen, given the frame design. Have it checked by someone who knows, if/when you can get professional help.
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