Here's another view of Jean Robic on his way to victory in the 1950 World Cyclocross Championships. Originally "colorized" in red and blue, this image is from the cover of "But et Club". I've changed it back to B&W for clarity. It's worth pointing-out that most cylcocrossers use more than one bike at each event, so there may be some differences. This particular bike appears to have MAFAC centerpull brakes up front, and cantilevers in back. Looks like cable stops attached to the top tube. In 1950 the four members of the French team took all four top spots at the World Championships!
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Aldo Ross
Middletown, Ohio, USA