Mike,
You could be correct about that. Maybe there is also a heat treating sequence that they leave out of the BMX version of the cranks in addition to the lesser finish. Something has to account for the drastic difference in the price of the arms when new. I suspect you may be correct that they are softer. A Rockwell test would tell the story.
Brian Baylis
La Mesa, CA
>
> Hi CR folks.
>
> I'm not convinced that the Campy BMX cranks really are the same as NR. The
> metal in our experience is softer than that of a typical NR crank.
> Messengers that beat up their stuff often had issues of tapers failing and
> the arms drawing in very far - problems not at all common on NR arms. Ones
> that we installed and maintained for folks also seemed to behave
> differently than NR's.
>
> My guess is that perhaps the molds were the same but perhaps the alloys and
> pressures used in the forging were not the same. I'm also under the
> impression that it is possible that fewer BMX arms failed than NR. Perhaps
> they are more ductile and less prone to certain types of fatique.
>
> I'm not certain about all this but but my gut feeling is that BMX and top
> Campy NR arms are just not the same animal. But they look and seem so
> similar...
>
> Mike Kone - Bicycle Classics inc.
>
> At 07:51 AM 10/26/01 -0700, Brian Baylis wrote:
> >Dan,
> >
> >Canpag. BMX cranks are cast from the same mould as N.R. cranks; the
> >difference is the finish. The polishing step before anodizing is either
> >left out or done less vigoriously on the BMX crankarms. Functionally
> >they are the same, but finishwise there is a slight difference if you
> >ever see a "silver" one. The red, blue, and gold ones are less obvious
> >on account of the color.
> >
> >Brian Baylis
> >La Mesa, CA
> >>
> >> Thanks to Mark B., Chuck, Dale and Tom Hanson for helping me solve my
> >> mystery of the Campy Strada single chainring cranks. To find they were BMX
> >> was a surprise!
> >> As far as I can tell, these BMX cranks are as well made and as highly
> >> finished as their NR counterparts. In any case, they look great on my 1985
> >> Bianchi Specialissima. Thanks again to all.
> >> Dan - gettin' cold in Beantown tonite - Borden
> >>
> >> At 7:58 PM -0400 10/25/01, OROBOYZ@aol.com wrote:
> >> >Yes, they are marked "Strada" and were for all practical purposes just reg
> >> >cranks with the inner chain ring shoulder machined off.
> >> >We have sold a smattering of them, most often as time trail bike cranks!
> >> >My shop employee Jason just built up his new fixed gear Landshark with
> them,
> >> >take a look:
> >> >
> >> >http://www.landsharkbicycles.com/photogal.html
> >> >
> >> >His is the 4th bike down.....
> >> >
> >> >Dale Brown
> >> >cycles de ORO, Inc.
> >> >1410 Mill Street
> >> >Greensboro, NC 27408
> >> >336-274-5959
> >> >fax 336-274-6360
> >> >www.cyclesdeoro.com
> >> >www.classicrendezvous.com