Folks,
I found this glowing but imperfect description of a Motobecane Super Mirage frame set's bottom bracket threading on ebay (item #250306607415):
"This would make a great fixed-gear bike, or city cruiser, or stylish single-speed bike...or just a nice-looking French machine if that's your style:
This is a pretty French frameset from the 70s, paint is in great condition and is a metallic light blue but is silvery, not really baby blue...logos are navy blue, very elegant. The fork is French threaded 25x1.0mm and the headset is included, it's steel with the modern 32mm octagonal top nut. Bottom bracket threading is mercifully the "Swiss" standard, which means left side is 35x1.0mm with right- hand threads (same as more common "French" standard) but the right side is reverse left-hand thread. This means you can start screwing in standard English 1.37x24 cups (the modern standard on nearly all bikes) and you should be able to talk your friendly bike shop into chasing the threads with their standard English taps if you want to modernize it...as it is, you can get an English thread cup more than halfway in by hand easily, so it shouldn't be too much effort to alter for using a cartridge or other modern BB, or you can keep it as- is and either use old used cups or a Phil Wood set of cups (see internet instructions for using them with Shimano cartridge bottom brackets, or use a real Phil cartridge...the cups alone are about $45)."
I despair for the future of the republic....
Jon Spangler
Alameda, CA USA