On 9/29/07, Sheldon Brown <CaptBike@sheldonbrown.com> wrote:
> Pat Moffat queried:
>
> >I recently acquired an unidentified bike on Craigslist. The BB fixed cup
> >is marked 'Campanolo con sfere DA 3/16" ',
>
> 'Man from the countryside with balls of 3/16"'
>
> > and the spindle is marked
> >'32-RN' on one of the flats. The spindle is otherwise unmarked. The
> >threading is English. I believe the crankset is a Stronglight model 57.
> >What is the meaning of the markings on the cup and the spindle flat?
>
> I believe that's the rare titanium Super Record setup. It's a
> collectors item if the spindle hasn't snapped off yet, probably worth
> big buckx.
>
> That's the only model I know of that used 3/16" balls rather than the
> usual 1/4" size. (Gave them room so the spindle could be a bit
> fatter than the standard steel one, in hopes that this would keep 'em
> from snapping off.)
I have one of these S.Record titanium spindles and, held side by side with a steel N.Record spindle, it looks like the same diameter spindle. Rather than having the races machined into the spindle itself, like steel spindles have, this S.R. ti spindle has steel collars pressed onto it with the races machined into them. But the curve of the race doesn't start at the surface of the spindle, like a steel spindle. It is machined into the top half of the collar. I should have taken a photo, but I think this is the reason that the ti spindle needed the smaller balls. Whereas 1/4" balls would roll right at the surface of the spindle, the little extra height of the collar above the spindle requires a smaller bearing to fit in the reduced space.
--Mitch Harris
Little Rock Canyon, Utah