C59 Cracked BB

[charliedid]

Garbage IMO

Sorry

[titans]

Originally Posted by r_mutt

just curious, how much do you weigh?

165 during the Summer and 170 in the Winter so weight is not the problem. Never crashed and no bone jarring pothole hits either. Time to move on. I’m in the queue for an Onesto.

[paredown]

Originally Posted by titans

165 during the Summer and 170 in the Winter so weight is not the problem. Never crashed and no bone jarring pothole hits either. Time to move on. I’m in the queue for an Onesto.

Not that it helps at all, but with five junctions with cracks, it makes me think this was a QC problem--IIRC, the C59s were glued up in batches in a continuous process--each frame start to finisih--not partially frames assembled and then completed...

New bike will be nice though!

[Mattbotak]

Maybe it was used in this video....https://www.youtube.com/watch?v=HhabgvIIXik&t=193s

[R3awak3n]

Pretty cazy. I bet a ton of ppls bikes out there have cracks than they don't even know. We all think a crack on carbon is terminal but carbon is stronger than we think so prob a ton more cracks out there.

[boywander]

Op- thanks for posting this. I found it fascinating to see there were a lot more cracks. I was thinking a couple more but not five.

The current market on super lightweight carbon frame scares me. Frame that is as light as 6-700g really made me think about longevity. In carbon frame less isn’t more. Only more prone to failure.
That said I would recommend all carbon frame should be checked regularly. If there’s any sign of creaking noise during a ride definitely have it look at.

[Toeclips]

FWIW
I refinished/repaired bathtubs for ryan homes

To find cracks on the surface of acrylic and fiberglass tubs, spider cracks, I would take a magic marker and cover an area. I would then wipe off the marker with alcohol, leaving marker where the cracks appeared.

For carbon frames this maybe a way to ascertain if any invisible cracks are lying below the surface.

I would only do this if your in doubt about your frame, simply because marker is difficult to remove, once it finds a fissure to settle into, hope this helps.

[titans]

There were no creaking sounds or anything that made me think there were cracks. No BB flex either. Only through visual inspection when cleaning the bike did I find it. Joe Bell knew immediately upon reviewing the pics I sent him that the crack on the bottom of BB was not a paint crack but a carbon crack. I had originally thought to get it repainted but when he told me this I sent the frame to Hottubes to get it fixed and then refinished. Toby then found the additional cracks especially in areas where the frame was painted white. He said extra white paint is needed to hide the black colored carbon so cracks are harder to fine through untrained eyes. Hope he was able to salvage it and give it to some up and coming youngster in the MA area. So beware if you see fine hair like lines in your painted carbon frames.

[Toeclips]

Good karma coming your way

[jimoots]

My limited understanding of carbon is that once delamination/cracking occurs, there is no structural integrity for the weave that has been delaminated/cracked.

If you crack one ply, but there are 8 underneath, it may still be OK.

With these colnagos with lugs that are somewhat overengineered, you can have cracks, delamination, etc and the frame won't actually fail. As the OP noted, there was no noise or flex (although the BB crack did worsen over time).

How does this occur?

Again, my limited understanding here, but if you are applying carbon and don't compact it appropriately you can create voids (a literal void / gap in between carbon ply) or creases in the carbon - both of which can promote cracking.

I've seen a few videos by Raoul / Leuscher Teknik dissecting Colnago frames, and the production does appear to be quite with issues cropping up at the lug junctions.

His sample size is not representative - he isn't dissecting frames that have zero problems, he's looking at ones that have problems, so the cross sections are always going to show up an issue.

But still, interesting - it certainly doesn't make me nervous about riding a lugged carbon frame, but I do wonder about the structural integrity of some of the cutting edge superlight stuff that is both light and has difficult-to-manufacture monocoque shaping.

[barnabyjones]

I had hairline cracks on a C50 at the head tube and BB. I rode it for years thinking they were due to flex and typical Colnago paint curing issues. Crashed in a race and damaged the drive side chain stay. Sent the frame to Calfee for repair and I asked them to inspect the "cracks." Paint issue only, according to them.

[C40_guy]

Sorry to hear about the fate of your C59.

It's a good reminder to check our bikes periodically for signs of issues or failure...I tap my fingernail along each of the carbon tubes every so often, listening for changes in the resonance, and do a quick visual of the other meaty parts (lugs, mostly)

My C50 is finished in nude carbon, so there's no hiding cracks under white paint!

[charliedid]

Originally Posted by titans

There were no creaking sounds or anything that made me think there were cracks. No BB flex either. Only through visual inspection when cleaning the bike did I find it. Joe Bell knew immediately upon reviewing the pics I sent him that the crack on the bottom of BB was not a paint crack but a carbon crack. I had originally thought to get it repainted but when he told me this I sent the frame to Hottubes to get it fixed and then refinished. Toby then found the additional cracks especially in areas where the frame was painted white. He said extra white paint is needed to hide the black colored carbon so cracks are harder to fine through untrained eyes. Hope he was able to salvage it and give it to some up and coming youngster in the MA area. So beware if you see fine hair like lines in your painted carbon frames.

I applaud the sentiment but do we really want a kid riding a compromised bike?

Bumer of a story for sure.

[titans]

Toby would fix all cracks before it’s passed on. He has good ratings when it comes to repairs and refinishing so I’m not too worried about it afterwards. It was too cost prohibitive for me to have all the cracks fixed and then the repaint. I’ve heard that he’s done this before as a way of giving back to the sport.