Chuck,
At least the French articles in Le Cycle never mention the "Extra" name. It's always "the latest model of the Campagnolo Gran Sport". Maybe Campy didn't use that name in their French publicity? Did they use the "Extra" also for the series-produced version introduced in 1953, or only for the 1952 ones?
Fortunately, the evolution of the Gran Sport is extremely well-documented in Le Cycle, with numerous Daniel Rebour drawings, so it is rather easy to piece it all together. It seems that Rebour realized this was an important development, and he treated it accordingly. For example, in mid-1952, he published a page comparing the "old" 1951 version with the "new" 1952 one. Obviously, all those drawings will be part of the VBQ article, which also is being reviewed by two experts on the subject, one in the U.S. and one in Britain.
Beyond a host of other differences, the 52 models also are easily
identified by their steel parallelogram plates, while the earlier 51
models are made from brass or some similar non-ferrous material
("alloy bronze," as Rebour called it). In fact, according to the
article, the rear plate of the 52-2 version (as on e-bay) is the same
as that of the 1953 series-production derailleur. (The 51 derailleurs
had flat, not curved plates.)
--
Jan Heine, Seattle
Editor/Publisher
Vintage Bicycle Quarterly
http://www.mindspring.com/
Jan Heine wrote:
>
> On e-bay, some nice photos of a rare second model Gran Sport
> derailleur from 1952... Item No. 2202249887
>
> According to the upcoming article in Vintage Bicycle Quarterly, this
> is version 52-2 (there were 51-1, 2, 3 and 52-1 before that). The
> next iteration was the series-produced model.
This version of the Gran Sport derailleur actually has a model name. It is in the 1952 Campagnolo catalog as a "Gran Sport Extra" (easily identified by the extended nose on the upper end of the outside pulley cage).
http://i7.ebayimg.com/
Chuck Schmidt South Pasadena, Southern California http://www.velo-retro.com (Timeline, T-shirts and reprints)
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