ashtabula!
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Bay Area K-Hound Charlie Martin suffers catastrophic failure of his BMC Road
More tubing detail shots on his Strava SFR Marin Mountains III 200K DNF | Strava
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Isn’t the down tube break right at the butte? (Sp?)
I don’t know much about anything but I’d blame the couplers. Given that this is local I’m sure Mike V will take a look
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I’m not familiar with S&S couplers other than the basics but it seems they would have some effect.
I think his frame exceeded it’s expected lifetime by a significant amount, couplers or not. Of the handful of steel frames I’ve seen that approached 100,000 miles (in this case probably ~6700 hours), half of them failed before reaching that distance.
Figure all the similar spec steel frames that failed way before such mileage/time, and the expected lifetime is probably around 3500-4000 hours/50,000 miles.
Obvious joke about giving him another BMC Road and riding it until failure to make sure.
Of note, IMO, the ED coating appears to have retained it’s effectiveness at the downtube but was burned away at the top tube coupler and corrosion is evident
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Ah perfect mine should be good for another 500 years at overall mileage per year but maybe 50-100 years at the current mileage rate
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I’d agree, failed at the edge of the butt. Couplers aren’t to blame.
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Yeah, dt had to fail before tt.
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Once that frame tasted freedom it needed to become its true unicycles self
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Simpler if the TT failed first but stayed partially together, and then precipitated the impact to the DT riding along until destruction
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Coupler looks clean. Braze fails. TT stays in socket. DT does the wiggety waggety that is how you break metal.
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Just out of curiosity, could frequently uncoupling the frame have anything to do with it? You gotta “un triangle” it every time and I always wondered how susceptible the tubes are to damage at that point, especially since it seems like this bike did it a lot (in a addition to the big big mileage)
Probably not unless there was overtightening or the coupler was slightly askew to the point the connection was torqued into failure.
Dude has 155k in rando credit from 2018 with 50k alone in 2021. A bike isn’t really made for that kind of use. Sure there are outliers but that ultra distance isn’t normal.
this should have had visible cracks before failure, right?
what’s weird to me is that both tubes broke rather than bending. so maybe they were both cracked and one finally let go, which caused enough stress that the other followed?
TT failed at the coupler attachment
DT failed at the butt
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our tandem is definitely out of alignment in some places, it makes closing the third coupler really challenging sometimes.
I’m imagining the kind of tail wagging that a seatpost bag might cause forcing issues to a head.
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for posterity’s sake:
Shortly after turning onto Hicks Valley Road, I got out of the saddle to pedal for a bit, and I heard a loud “SNAP!” and felt a jolt. I looked down thinking maybe I had snapped my chain, but it looked fine. Maybe it was just a bad chain skip? Oh well, I’ll just ride a bit more and see if it’s resolved. I took another pedal stroke and was met with a loud “CRACK!” and before I knew it I was on the pavement in a pile of bicycle, with blood leaking out of my knee. It took me several moments to make sense of the situation. Did… the front just fall off? That’s not very typical.
and from the comments:
89,243.5 miles on the bike according to Strava. It’s taken enormous abuse, and I suspect all the disassembly/reassembly for all my bike travels aged the frame pretty rapidly, especially in humid areas like the east coast. I can’t fault the frame at all.
Downtube:
Toptube:
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I was wrong. It just broke
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