My favorite vintage-ish go-to for tricky shifting problems on vintage cranks has long been the Suntour Sprint fder. Nice flat cage plates, longish cage but not too wide.
Like a lot of both vintage and modern fders, it doesn't have a great cage profile for smaller outer rings, but I find it still works well, even on vintage flat, ie no pins/profiles, chainrings.
Don't have any great photos handy, but here's a Sprint fder on an Echelon/Cherubim Odyssey:
Originally Posted by
The Golden Boy
A few years ago, I was in a FD search for a sort of retro-mod sort of thing- I tried using a modern-y triple derailleur and it wasn't working with an old crank set. These were the choices I had on hand:
Front Derailleurs by
Dave The Golden Boy, on Flickr
At the time I chose the Cyclone- just because it looked a touch more modern than the Mountech.