I have a pair of old Hella horns that were mounted to the crashbar of my '64 R69S. They barely buzzed, due to wiring problems--there was a cobbled-together relay under my gas tank for them.
Does anyone know if anyone rebuilds these old horns? They are the snail-shaped type with chrome back side bowl-shaped covers. I've seen them frequently in old pics of the Tour de France on the officals' /2's.
Also...any modern relay recommendations? I am getting my bike rewired.