Originally Posted by
dddd
Sedisport chain was one of the first narrow (~7.2mm) chains, and the first to use no discreet through-bushings.
Shimano's first narrow chain was their ~1977 "UG-Narrow" chain, what I consider to be the very first entirely modern bushingless narrow chain, copied by everybody and still sold to this day (in re-named and HG-reinforced form) having identical design and dimensions as the original.
I believe that Suntour's Ultra-6 chain preceded all other narrow chains for derailer bicycles, but these still had bushings connecting their inner plates, so less flexible and thus having more cross-chaining friction.
I got an ultra-6 new-in-the-box when they came out, went touring with it. Was only a week but three of the bushings disintegrated; having a chain tool meant I could keep going; I lost the two bottom gears.
Then I got a Sedisport and that was *much* better.