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Patents on Rapide Engine?

herbswoods

New Website User
Non-VOC Member
Vincent H.R.D. Club Members,

I'm currently writing a 2-part story for "The Antique Motorcycle" magazine (USA) about the Harley-Davidson high-cam KL model of the early 1950s. This bike was intended to match or exceed the performance of the best Brit bikes, but never made it out of the prototype stage. Instead riders got the lack-luster Model K/KH (with side-valve engine) in 1952-56 and later (1957) the XL model "Sportster," an overhead-valve machine still being produced today.

In my research on this high-cam KL model, its trail crosses that of the great Vincent Rapide V-twin in a couple of different ways. One is that the Milwaukee firm may have looked at the Rapide engine for inspiration when designing the high-cam KL motor, and I already stated that in Part 1 of the story.

But more critically there is an American published work called the "Harley-Davidson Data Book" (p. 87) where under "H-D Board Minutes" for 1953 the author claims that the KL motor was dropped due to "patent restrictions" with the Vincent motorcycle company.

While that reads like fact no one from Harley whom I interviewed mentioned any patent issue. That's not to say that a patent issue didn't possibly exist, but in searching I have not been able to find any reference to patents covering the Rapide-type engine. In addition, the "H-D Data Book" contains many mistakes, including several errors listed under "Board Minutes," so I'm suspicious that this might be another one. Thus I'm wondering if you Vincent experts can set the record straight on this patent issue.

Were there any patents issued that covered the Rapide-type high-cam engine held by Vincent or Phil Irving or anyone else that Harley-Davidson might have been afraid of? If there are such patents, can you direct me to an online source so I can examine them?

That Rapide engine was a stunner. Like many other times you Brits were ahead of us in the motorcycle game.

Thanks for your help,
Herbert Wagner
USA
 

Ken Targett

Active Website User
Non-VOC Member
Running the Vincent H.R.D. Owners Club online forum costs money, and like other organisations, we have annual software and hosting costs which are significant. These costs are paid for entirely by the Members of our Club. Sadly, we don't have a magic money tree!

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Ken Targett

Active Website User
Non-VOC Member
Running the Vincent H.R.D. Owners Club online forum costs money, and like other organisations, we have annual software and hosting costs which are significant. These costs are paid for entirely by the Members of our Club. Sadly, we don't have a magic money tree!

If you're viewing this annoying messsage, you have been identified as a regular non-Member user of our online forum for some time, and we’d really appreciate it if you could give some thought to joining the Club to offset some of the costs mentioned previously.

You can join the Vincent H.R.D. Owners Club, remove this annoying message, and gain full access to all website facilities by CLICKING HERE.

 

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