Another question from a few years ago asks about Shimano 11-speed derailleurs; I have a related question about current (2021) Campagnolo equipment - I'd like to understand what downtube (friction) shifters will work with a Campagnolo 11-speed derailleur.
What is the cable pull required between top and bottom gears, and is it the same as for 8/9/10-speed systems? I thought that the total derailleur travel was the same, just with narrower spacing between gears, but I see that Dia-Compe make a dedicated 11-speed shifter with a larger diameter for greater cable-pull.
How well do friction shifters work with Campagnolo 11-speed cassettes (if at all)? And which ones?