for gearheads only.
(Linked by a quite different search topic., not even cycles.)

The tale of mixed-up drawings on a desk just seems.. universal? for creating an {{Idea!-balloon}} in wetware.
I'd always wondered how Irving thought up the various features--he'd already copped to the forked rocker-arm solution to keeping valves centered as they worked;
I thought he had had the twin in back of mind, all along.. Nope.

Also the stat: fewer than 11,000 Σ Vincent machines produced, yet the interest today is ~~ early Ferraris, maybe because of the beautiful, clean eye-candy form yet performance to match.
Any modern hi-tech design eclipses every spec. Will be interesting to see if many of them have the soul to attract as many fanbois as Irving's creation, in 30 years or so.