I was looking through the previous years on youtube and remembered the George Hincapie snapped steerer tube- did they ever work out what went wrong. How pissed would you be? :lol:
The fork had carbon blades, and an aluminium steerer. Failure was at the stem.
Steerer was shot peened, which can improve fatigue performance, and anodised for corrosion resistance.
The likely cause was the crash earlier in the race, which would have initiated the crack, and then continuing to ride it over the pave grew the fatigue crack (faster than it would have on smooth roads) until catastrophic failure occurred when there wasn’t enough material left to bear the load. Additionally, the stem/headset may have caused a small notch/stress concentration which help to accelerate failure.
Carbon isn’t a long term (i.e. >5yrs) frame material. I wouldn’t buy a 2nd hand carbon bike/fork/stem/bars… I’ll happily ride a 50yr old steel frame given a check over for cracking etc.
Guy walked into a bike shop one day while I was there, had a carbon frame (a GURU, very expensive thing from Canada).
He had t-boned a car. Carried the frame in a green garbage bag, there wasn’t a piece of it more than about a foot long, all with shards of jagged carbon sticking out everywhere. I think that’s what we call “catastrophic failure”.
Carbon beats steel until they introduce notches. Then Carbon fails catastrophically, steel bends. Not a comforting thought when you’re bombing down a steep descent.
I remember talking to an ambulance officer during a ride and he mentioned that in recent times the major injury that cyclists experience in a big crash is all the little shards of carbon that get embedded in the skin. Apparently it’s worst than having your bones broken. Something to think about.