Raymond Bon was the clever Parisian designer of the Spirax derailleur system, one that evolved & improved from the early 1930s into the 1960s.


“(Spirax derailleurs) were designed as touring deraileurs, with a large capacity of 38 teeth. …(snip)…I have one on my 1951 Raymond Valance, and it’s performance is remarkable, much better than my Nivex-equipped bikes, which in turn are better than my Cyclo-equipped bikes.”

Gary DellaRossa on the Classic Rendezvous Google group.

NOS Spirax shifting set

on eBay by seller kirvesmies

Have you a vintage bicycle with Spirax derailleurs?
We’d love to have some good pictures of that set up.
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