Search for (engineer) "jobst" in rec.tech or on the late Sheldon Brown's pages for analysis of stress risers.
Jobst broke more than one during his long alpine cycling career.
Would engineers here comment on how thorough the polishing of the sharp-edged web should be to keep these stress fractures from occuring, if it can be prevented at all?
Would collectors comment on whether they would buy or spurn a Campagnolo spider whose sharp edge was finished by a previous owner this way?
Harry Travis Washington, DC USA
On Mon, Jan 19, 2009 at 2:07 PM, Kirke Campbell <
passionateyouththing@yahoo.com> wrote:
> I just bought a (non-CR timeline) Debernardi track bike off craigslist. Got
> a great deal on it. Gold/Black paint scheme looks like its from the 90s.
> Came with a mix-up of parts...Stronglight headset, Suntour Sprint track hubs
> on Fiamme tubulars, and the cranks were mismatched, drive side old (on
> topic!) Campy Pista and the left side Strada.
>
> I took the bike apart for cleaning and noticed that on the drive side crank
> arm there are two tiny cracks about 2mm long at the base of two the spider
> arms. I have heard that Campagnolo cranks are notorious for this problem but
> have never seen it in person until now.
>
> Should I be worried about the structural integrity of this crank arm? Is
> there anything I can do to stop the cracks from spreading?
>
> Thanks!
> Kirke Campbell
> Houston, Tx