Frankly judging from the photos, there could be several possibilities. Unless each of us was a carbon particle resident in that right chain stay at the time it snapped, none of us will know for sure.
Murphs wrote:Photo sequence (don't ask for more, there aren't any):
Well, this last shot shows the stays "sprung back" to a degree once torque loads were been removed, and also the r/mech still on it's hanger (so definately NOT a mech in the wheel).
Looks very much like QR/axle failure - wheel pulling out and to the right under high torque load - stays flexed beyond limit then failing. This would be apparent from tear fractures on the inside of both stays. If it's a frame failure at fault, there should almost certainly be compression/crush failure evident on the chainstay (seatstay could have failed as a result and still show the internal tear failure). Cracking on a chainstay prior to these photos would have to crush to fail (shortening the stay and locking the wheel) as the stays are under compression loads, but the frame would feel "soft" long before catastrophic failure. Obviously without detailed photos or examination this still cannot be proven and is just my theory from over 20 years as a composite structures developement engineer (before semi-retiring to shop ownership).
@Walkercycling - No offence meant, sorry if any was taken, and I certainly didn't call you a liar (although re-reading my post I can see how you may feel it was implied - unintentionally I may add).
The dropout that we can see doesn't seem to have any damage, and if the wheel was clamped on both sides by the skewer, breaking a chainstay or seatstay would not likely cause the wheel to come out of the frame like that...unless the QR broke or came out in the failure (which is unlikely IMO).
My guess is that this is user (or mechanic) error and that Specialized will likely cover it under warranty regardless...
I'm totally perplexed though - if both seat and chainstays snapped, how is not eating bitumen? Without anything else to go on, I'd have to give credit to Specialized for making a frame that still supports a rider on half a rear end with both stays busted.
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This was apparently a JRAWIPWTB*breezerboy wrote:Just so you guys know, the rider in the picture had a mechanical issue earlyer befor this happened ... not sure if he had the wheel swaped or just looked at but from what i have herd the wheel fell out of the dropouts or pulled out and thats when the frame broke, probably due to the quick realeas not being tight enoughI was behind him on the first lap. Whenever he got on the power the wheel would jump to the drive side for a second and then back to its normal spot again. I thought he had a buckle in his Zipp but when he pedalled easy or coasted it was dead straight.I also noticed his gears jumped around at one stage.
I moved up and told him I thought his wheel axle was broken, as it certainly wasn't he QR. After that I stayed ahead of him as there was something seriously wrong with his bike and I didn't want to be behind it.
Obviously issues were there before the failure, but he kept riding anyway. OK, so it was a race, but you certainly can't say the rider was blameless in the severity of the failure.
Did the mechanical cause the failure, or was it a symptom? Who knows, but without more details or further inspection you cannot say this is a "frame failure", just as I cannot say it was rider error/poor build.
* Just Riding Along While Ignoring Problems With The Bike
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