Originally Posted by
clubman
If you want old school derailleurs, you'll never shift a 17-26 freewheel. Cyclo Standards generally shifted in 2 tooth increments and not well at that. If you added a double chainwheel, I'd expect it to blow up.
What about a wide double in the front, maybe 9 tooth spread, with just the original 17 tooth on the Sturmey Archer hub?
Is there any vintage-style derailleur that could handle a wide double?
Recall that to build his custom René Herse, Jan Heine made or adapted a suicide shifter to handle a wide compact double. I take a little confidence from this. Plus I’m using a simple Huret with a 39/53, no pins or indexing.