What broke? Carbon or Alu?

George Hincapie's stack due to a broken fork steerer. Was it Carbon or Alu? (The steerer that is)

http://www.youtube.com/watch?v=PBzeQQs97YA

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It was an black anodized aluminium steerer. He used it as it had clearance and dimensions for paris-roubaix. very strange that it should break though. Conditions must be so much worse than we can imagine. Must have fatigued mighty wuickly with the cobbles.

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BMC SL01
SRAM Force


thank you crank n' cycles...If you are ever in SW WA, take a trip to Crank N' Cycles.

He had a crash earlier in the race-not sure if it was the same day or not. They figure that created the lead up to the failure.

Hincapie is not the sharpest tool in the box. In the days before P-R he and the team tested wheels they intented to use. He was intentionally bashing into potholes trying to break the wheels. Who know what damage he may have done to the steerer. He then had at least one crash in P-R before the failure, and he ignored noises from the bike thinking it was a loose headset.

If I remember right the fork itself was not one of the high end products from Trek. It was something from their commuter range. This was used because it had a greater rake, improving comfort on the cobbles. There seems to be some confusion over the exact fork model. Trek gave some information that did not match up with post crash pictures.

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"You are like the wind and I like the lion. You form the tempest. The sand stings my eyes and the ground is parched. I roar in defiance but you do not hear. But between us there is a difference. I, like the lion, must remain in my place. While you like the wind will never know yours." -- Mulay Hamid El Raisuli, Lord of the Riff, Sultan to the Berbers, Last of the Barbary Pirates

Ah, that makes sense then...

I seen a few forks here and there on ebay and online shops and some have alu and some have carbon steerers... Always wondered which is best, but when I saw that vid I thought hmmmmm wonder what material that was...

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carbon steerer is better. It is lighter and because it is monocoque, there are no bonds to break. You do have to watch tension though.

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BMC SL01
SRAM Force


thank you crank n' cycles...If you are ever in SW WA, take a trip to Crank N' Cycles.

Even if it wasnt high end it had been reworked by Trek. for example, the aluminum steerer was shot peened (for strength).

Having seen a lot of this failures, in my mind this area is the weak-link in an A-Head system. I also think that an aluminum steerer will be prone to this failure more than any other material.

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Carbon and aluminum both have vulnerablilities as a steer tube material, but it's pretty ridiculous to blame the steerer - the blame lies in the earlier crash and ignoring the warning signals. It's completely possible for a carbon steerer to fatigue in the same way. It won't happen to you because you wouldn't go pounding over a hundred km of cobbles after a crash and a headset that feels funny.

Whether it's pounding over cobbles or silky smooth roads is not what I am talking about. From experience I have witnessed many cases where the steerer broke just like hincapie's. These were all road bikes during crit races and 1 during a high speed training ride. In all cases the roads were smooth and the steerer just gave way and in all cases the steerer was aluminum and and A-Head set up. I am yet to see this happen with a steel, ti, or carbon steerer. The point is aluminum gives no warning when it snaps specially when using an A-Head set up. This wont happen on a quil system. And yes it has happened to me - an aluminum steerer - not abused and used only on paved roads!!! Again I repeat what I think is the weak link on an A-Head set-up and that is the area on the steerer just below the stem.

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you can see the full spec here http://www.cyclingnews.com/road/2006.../hincapie_trek

Nope - steerers do not just give out. I don't care what you've seen, it doesn't happen. There was existing damage in every one of those cases, or there was improper installation, or a singular material fault. I don't want to get in a pissing contest with you, but I don't want the readers of this forum to be needlessly frightened of a perfectly good component.

Exactly. There is no way for a steerer to "just break" while JRA, unless there is previous damage.

Reynolds even addresses this in it's owner materials that things just don't break while JRA.

You just reinforced my point - steerers break because they get damaged due to fatigue. The existing damage you say is there is due to fatigue. And more than any material used in the bike industry aluminum is more prone to fatigue (its a no brainer).

And improper installation or not - carbon, steel or titanium will not break and cause an accident in that spectacular fashion. Contrary to general belief, after the advent of the A-Head system, it is the steerer that breaks more often than say fork crown or fork legs.

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No, and as I've said many times, the BS on this forum about fatigue is astounding.

All fatigue failures start with an incipient crack. Steel, titanium and aluminum will all fatigue in the same way (more or less) once the crack has started. Hincapie's steerer made of any of those materials would have broken in a similar manner. A steel or ti tube may have given a little more warning, that's all and maybe not even that (actually I'm not even aware of any ti steerer forks). A carbon tube probably would have shattered in the earlier crash to begin with - from some observation point I guess you can say that's better.

Do not fear the aluminum steerer! There's no way you'll ever see enough cycles to fatigue one without crash damage.

Kestrel used to have a Ti steerer option for their fork ... that may still be an option.

I have a Titanium fork (presumably of Russian heritage which I got from a UK vendor) which has a Ti steerer.