In a message dated 6/26/02 3:12:45 PM Eastern Daylight Time, classicrendezvous-request@bikelist.org writes:
> Craig Sandvik wrote:
> >
> > I always wondered if the classic "campy crack"
> > in the web could grow all the way into the arm.
> > Now you know:
> > http://www-tec.open.ac.uk/
>
To which Chuck S. added:
> Quote from the web site:
> "This was a high quality component that had very high load cycles but
> was in excellent apparent condition until the final fracture that
> unseated the rider in heavy city traffic."
>
> I think what is interesting here is "had very high load cycles," but
> with no further detail on just what that refers to.
>
> In 25+ years of daily participation in the bike scene in Southern
> California I have never seen nor heard about a Campagnolo crank failing
> in this manner. Doesn't mean it can't happen, just that in my opinion,
> it is very unlikely.
>
> Just guessing? It sounds like the rider was very, very large.
>
> Chuck Schmidt
> SoPas, SoCal
>
>
Wow!
Note the depth of the toe strap rub. I'd wager this his crank had millions of cycles on it.
That said, I also have never seen one go completely to failure. It would be interesting if we could get an accurate estimate of the number of miles on this crank at the time of failure - it certainly was a whole lot!
I'm guesstimating about 1 million crank cycles per 2800 miles of use (at 90 rpm and 15 miles per hour)
28,000 miles would equal 10 million cycles of the crankarms!
100,000 miles would equal 36 million cycles!!
Greg