Weird discolours on CF frame
09-12-16, 07:29 AM
#1
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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..?
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..?
09-12-16, 10:37 AM
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I'll hazard a guess that moisture got under the clearcoat.
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.
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?
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?...
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.
The frame was never damaged the paint is not peeling..
By looking at it/gently knocking the frame feels solid.
09-12-16, 02:06 PM
#7
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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.
09-12-16, 05:50 PM
#8
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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.
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.
Flat pedals tho are a much more immediate concern.
I will go clip ins 
