This is a tatty example of a rather fine catalogue. It features the traditional helically driven Le Cyclo derailleur - now called the Cyclo Touriste, but also a pair of chain-pull derailleurs, the Cyclo Route for touring and the Cyclo Sport for racing.
I can find no printed date anywhere on this catalogue. I have dated it at 1951 because it contains the information that Cyclo has been a registered trademark for 25 years. I believe that Cyclo first registered its trademark in 1926.
Tellingly, while 6 pages of the catalogue are still devoted to derailleurs, 6 other pages are now given over to freewheels and chainwheels. After the Second World War, Cyclo was moving away from derailleurs and becoming a freewheel manufacturer.
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Cyclo Sport 1951?