According to this Campagnolo timeline:
http://www.campyonly.com/
that would be 1978, with the whole raft of other (and mostly rather silly) CPSC-mandated mods to the Nuovo and Super Record gruppos.
Parenthetically, I have always personally preferred the curved QR levers as they are both more comfortable for me to use and provide a visual cue to whether they are in the open or closed position.
Kurt Sperry Bellingham WA
On Thu, 19 Aug 2004 12:07:41 -0700 (PDT), Vladislav Luskin
<vladluskin@yahoo.com> wrote:
> When did Campagnolo switch from flat quick release skewer to curved? Thanks a lot,
>
> Vlad Luskin
> SFCA
>
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