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Weird discolours on CF frame

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Weird discolours on CF frame

Old 09-12-16, 07:29 AM
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Weird discolours on CF frame

Hi,

I bought an used BMC Granfondo 01 (CF frame).

The frame is solid no chips no cracks.. but its full of weird discolours.. They look like there would be stickers in the places where discolours appeared.. The paint is solid in the places of discolours..

Any ideas what that could be..?
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Old 09-12-16, 10:37 AM
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I'll hazard a guess that moisture got under the clearcoat.
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Old 09-12-16, 10:40 AM
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Looked like bubbling/delamination of the clear coat to me, but didn't want to comment for fear of being chastised by the CF defenders here.
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Old 09-12-16, 11:48 AM
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It looks like the surface is a bit ripply in the questionable areas, like bad bodywork. Have you asked the seller if the frame has ever been repaired? Did seller disclose any peeling paint issues?
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Old 09-12-16, 12:16 PM
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I got random grey decoloration on Ritchey carbon fibre seatpost (black colour) after 6-7 months of using the bike only on dry weather. I never thought it might be an issue (other than aesthetic). There is no sign of crack or any kind of weakness on it, but... who knows?...
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Old 09-12-16, 12:48 PM
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Hmm.. I looked at pictures of other BMC Granfondo.. seems that all BMC's are having the same thing..

The frame was never damaged the paint is not peeling.. By looking at it/gently knocking the frame feels solid.
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Old 09-12-16, 02:06 PM
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I don't know if it is what you are describing, and can't see it from the photos you took, but it is typical of a 'raw' finish frame to see where the various layups intersect with each other as a change of texture. If your fingernail doesn't snag on the seams, I imagine it's fine.
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Old 09-12-16, 05:50 PM
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I don't think I've ever seen a carbon anything without a little weird variation in the surface finish. Probably why so many persisted in putting the decorative woven outer layer on everything, it hides so much of that stuff and makes the product look better.
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Old 09-13-16, 02:34 AM
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That looks pretty typical of visible carbon layup underneath a thin coat of paint.

Flat pedals tho are a much more immediate concern.
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Old 09-13-16, 05:05 AM
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hahahaha kibbler.. just getting used to it I will go clip ins
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