Phil Vincent had yearned to build something to outperform the Brough Superior SS100, which had ruled unchallenged since the 1920s.

Britain’s postwar steel shortage made Vincent’s now much-copied frameless construction their choice—the steering head attached to the cylinder heads via a welded sheet metal box—that was “the frame.” 

The result was an extremely compact 1,000cc V-twin of unmatched acceleration and speed. Nothing else came close, but production was limited by high price. 

Think of this bike and doesn't the photo of Rollie Free, horizontal in bathing shorts, setting a 150-mph record at Bonneville, pop into your mind?

 https://cars.bonhams.com/auction/17318/lot/40/rollie-frees-personal-archive-of-papers-photographs-letters-and-ephemera/#photos 

https://www.cycleworld.com/blogs/ask-kevin/kevin-cameron-top-picks-from-mecum-las-vegas-auction/