Will thumb shifters fit on bullhorns or road drops?
I purchased my bike from an abandoned bike auction a few months ago. The original STI levers were missing. I can't afford STI or barend 9-speed shifters... or even barend friction shifters. It has no braze-ons for DT shifters and threadless stem (so no way to mount stem shifters). My only option seems to be thumb friction shifters. The thumb shifters are usually for mountain bikes, so I don't know if it'll fit bullhorns or drop bars (I know the bar diameters between mtn and road is just slightly off).
I was considering these:
Shimano Tourney thumb shifters, but I don't know if the indexing can be switched to friction to support 9-speeds.