I have noticed the GS front derailleur on Coppi's bike in TdF
1951 had different guide plates from ones I see. The outer plate
was shorter than inner plate and had the wheel and wing logo ,
not the earth logo. ( D. Rebour's book " World of D. Rebour" p.
117) And I know the sfift lever band then was 2 stripes type.
On the Campagnolo catalog No.12 ( Reprint of Velo Retro, p. 13) I see complete GS front derailleur had the earth logo but the guide plates (cage) drawn just below it had the wheel and wing logo and the outer plate was longer. And the shift lever band was the ordinary one.
I would like to know whether the GS derailleurs on the 1951 bike came into the market or not. Were they supplied only to racers ?
Many thanks in advance.
Hachioji, Tokyo, Japan