I believe the first parallelogram derailleur was the Campagnolo Gran Sport first generation - 1951.
Giles O'Bryen London, UK
Message: 11 Date: Sun, 30 Jan 2011 21:39:54 -0500 From: email@example.com Subject: Re: [CR] Zeus... Maybe Simplex was not earlier To: firstname.lastname@example.org, email@example.com Message-ID: <8CD8F0746C5B734-2264-1EF59@Webmail-d111.sysops.aol.com> Content-Type: text/plain; charset="us-ascii"
Just heard from a knowledgeable person that perhaps Simplex did not pre-date Campagnolo with double parallelogram rear der. I could be wrong, I have no data on hand to support that idea, just thought I remembered that. Will happily defer to someone who knows this detail...?
Greensboro, North Carolina USA