Jonathan,
Simple lack of availability. For some reason the BB shells seem to have ceased production in the very early 60's. I think lug production continued for many years after that. To my crcollection, the latest date frame I own with a Nervex BB shell is my 1962 Masi Special. Paramounts seem to stop having Nervex BB shell about the same time. For some reason the BB shell went the way of the dinosaurs. The Nervex BB shell is a good one, but not anything exceptional.
Brian Baylis
La Mesa, CA
>
> Hi all. I've been perusing the neat custom frames of fellow list-members
> (some of which were made by listmembers -- how incestuous) and stumbled upon
> what seems a relatively uniform aspect of the frames built with Nervex prof
> lugs. In particular, none of them seemed to make use of the Nervex prof
> bottom bracket shell. I've also got a custom frame of my own and it
> doesn't use this bottom bracket shell either; instead it has what looks
> to be a modified Henry James bb shell. Why don't builders use that
> shell?
>
> Jon Cowden
> Ithaca, NY