RE: Is it a recognized truth . . .
Mick:
The 1000cc Vincent bikes were the Rapide, the "Normal" touring bike, the "Black Shadow," which was a lightened and more powerful version of the Rapide. Finally there was the "Black Lightning," a;so commonly just called the "Lightning." This last was an even more lightened version, built to order, a real fire breather.
With careful tuning the Shadow would peak out around 140 mph. Doesn't sound like a lot now, but you have to remember we're talking about the early 1950s, when a fast Ford would just barely make 100 mph. And all the Chevrolets had only six cylinders.
Sid's Lightning, the "Rattler" I mentioned, ran that speed in a 1/4 mile drag, burning alcohol.
Some Jap company (think it was Honda) greatly insulted the memory of Vincent by calling one of their rice burners a "Black Shadow." And now there's a fellow on the west coast who has bought all rights to the Vincent name, he's trying to get production started on a "New" Vincent with a Jap engine. An even greater insult to Phil Vincent.
Bill.
PS: Sorry Dick, this one has really gone off topic. My last Beezer was a "Big Valve Super Rocket" 650cc. wr.