As a data point, my '71 SC has the hex/non-allen binder bolt. The Allen bolts seem to roughly coincide with the bike boom.
Kurt Sperry Bellingham WA
On 2/27/06, Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net> wrote:
>
> Nice work. There is an older type bolt, like came on my 1973 (or maybe
> 1972) Windsor Pro, which copied the Cinelli seat attachment. Rather than
an
> allen head, it had a protruding hex nut for a regular box end
> wrench. Pretty sure genuine Cinellis had the same bolt. Anyone know whe
n
> Cinelli switched to allen head?
>
> --
> fineartscrimshaw.com