The greatest derailleur of this period is imho the 1st generation suntour cyclone, like on my 1977 sekai 2500. This derailleur, introduced in 1975, was the best shifting derailleur on the market (according to frank berto), and almost the lightest - at 175g - only the huret jubilee could beat it. Not only that, the aesthetics were imho second only to campy stuff. And it cost 40% of a campy derailleur.
It was such a screaming good buy that suntour in the early 1980's introduced the Cyclone II, with that 1970's cheesy font, and lots of extra chunks of metal, to pump up the weight, and get rid of the engravings on the front and rear derailleur (rear outer parallelogram strongly reminds me of campy). This left the superbe derailleur as top of the line, but 1st generation cyclone was imho just as good at shifting and aesthetically the nicest derailleur that suntour ever made.
- Don "owns 4, used to own 5" Gillies San Diego, CA