The most rare Campagnolo part - I think that goes to the first Campagnolo Gran Sport derailleur from 1949 - the one that was the Nivex copy with two wires and no return spring.
At least one was made. It was shown at the Milan trade show. Daniel Rebour drew it. I have seen no other mention of it. Nobody I know ever has seen one. Bicycle Quarterly published two photos (Vol. 2, No. 2), but they came to us with no explanation, and for all I know, they may show a replica.
Most rare? With perhaps only one made, it must be at least a strong contender. Most significant? All modern derailleurs can trace their ancestry to this one - the first parallelogram derailleur that was mounted on the rear dropout. Frank Berto called it the "Holy Grail"... What can I add to that?
If anybody has seen one (perhaps _the_ one), please get in touch.
Jan Heine
Editor
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