[usrusr]

That's why I wrote "individual travel" in my original post. The core of what I was getting at is that for many of those fascinated with the bicycle at that time the human powered aspect simply wasn't part of why they loved it. They moved on to e.g. motorcycles as if it was just the next stage of the same thing. Or directly to aviation, as a certain pair of brothers who ran a bike shop did, not before contributing a design tweak to bicycle technology that's still present, unchanged, in almost every bike available today including for example those that were used to win this year's Tour de France (and most likely every iteration before).

[pmontra]

The bearings as described in the UPGRADES section at https://wright-brothers.org/Information_Desk/Just_the_Facts/... ?

[usrusr]

Actually I was referring to the pedal thread thing that's an amazing improvement over the hassle pedals would be if they were both right-handed. And those pedal threads are still in use with far less change than their bearing innovations. There have been competing thread standards since then (all using that improvement), but much less than in any other place on the bike. Chances are that you could install the latest clipless carbon powermeter pedals (featuring 64MHz Cortex-M4s) on many pre-war bikes, from back when world wars didn't have an episode number. And they'd just work.