Legend has it that Australian engineer Phil Irving placed a
tracing of the Vincent 500 motor on top of a drawing of the same motor
in such a manner that it formed a 47° V twin. True or not, there was
an excellent reason for the chosen angle in that tooling costs for the
new motor could be kept to a minimum.
Prior to WWII, Phil Vincent bought the rights to the Howard R. Davies
company, (founded in 1924?), and adopted the name Vincent-HRD for his entry
into the British motorcycle market. Other than the name, there was little
similarity between the HRD and the new model, a J.A.P. powered single released
in 1929.
The new Rapide was announced to the world in 1937. One statement in
the press read: 'The idea behind the design, is the production
of an exceptionally lively, high-performance mount with the same superb
handling as the smaller models in the range. Not only this, but the makers
have aimed at providing a 100 mph machine that is docile and does not rely
on supertuning for its out-of-the-ordinary capabilities or require an ultra-high
compression ratio.'
The Series A Rapide had many innovations, not least of which was the
cantilever rear springing system already proven on the single-cylinder
Vincent HRDs. Decades later Yamaha introduced their monoshock system -
for all intents and purposes a straight copy of the Vincent system. The
Rapide's other features included a stainless steel tank, twin brakes on
both wheels, and a duplex primary chain connecting the powerful V twin
engine to the Burman four speed gearbox.
These machines proved fast and reliable, and sold reasonably well up
until the onset of war in 1939. The Series B Rapide was announced in 1945,
very shortly after the war's end. The new machine had many refinements
and changes including a 50° cylinder angle and internal oil galleries.
This basic layout was retained for the C and D models, the last of which
was built in 1955.
