I have a track bike numbered 999082 that I believe to be from the early to mid 50's on account of its bottom bracket shell, which has a "lip" around the perimeter of the openings for the BB cups.
We might have more success dating the bikes by tracking design features in conjunction with the serial numbers... and also maybe not. I was surprised to find a seat-bolt binder arrangement in front of the seat tube on this 1955 bike (which is going for cheap at the moment!):
Tam Pham Huntington Beach, CA - USA
On 10/25/07, dave martinez <dmart84815@yahoo.com> wrote:
>
> Hello All,
>
> Not a new Dan Brown
> novel.
> Has anyone broken the Bianchi serial number codes?
> Specifically bikes from the 50s and 60s, like the Campione del mondo.
>
> I recently became the proud owner of what the former owner thinks is a
> 1954. The serial number is 526792.
> Whats the serial number on your 50s Bianchi and the alleged date of
> manufacture?
>
> Regards,
> David Martinez
> Fremont Ca
> US of A