I drove around Europe at Easter in 1971 and don't recall seeing a Solex moped except in Amsterdam, where there were quite a few of them. They weren't really competitive even there, though, where there were more mopeds than bicycles, and far fewer cars than bicycles. The young people were riding what I would call "cheater" mopeds: they had engines right on the size limit, fairly highly tuned, with 4 speed foot-shift motorcycle-style gearboxes and manual clutches. They had two cotter pin positions in the pedal shaft, and were only ever seen with the two cranks beside each other and both of them pulled up out of the way of the regular motorcycle pedals. In other words, they were motorcycles with some pretend-pedals on them to make them legally mopeds. Only elderly people were seen on Solexes. It is interesting that Honda didn't ever make a cheater version of the original Cub: I think it might have sold, and still be selling now.