Bike Find of the Day – The Vincent Black Knight
There are some motorcycles which simply stir the soul, and the Vincent Black Knight managed that feat and has kept on a roll for the last fifty-five years. A combination of design and performance made the Black Knight unique for its day, and it was that marriage of the two things motorcyclists covet which has ensured the survival of this iconic machine in the public imagination.
The Black Knight was made between 1954 and 1955 by Vincent Motorcycles, and a year before the Vincent factory closed in 1955, the firm produced the enclosed range of Black Knight and Black Prince models. Called the ‘Series D’, the Black Knight was based on the Vincent Rapide. It was the enclosed bodywork which made the Black Knight a special piece of motorcycle art, and it had the additional benefit of improving performance by directing air to the rear cylinder
Development of the Vincent Black Knight
The Black Knight was launched at the 1954 Earls Court motorcycle show alongside the 998cc Black Shadow. This enclosed version of the magnificent and legendary Black Shadow.
Production of the Black Knight began in the spring of 1955. Lucas components replaced the less reliable Miller electrical system and ignition was upgraded to a coil and distributor configuration. The stylish rear enclosure, which also incorporated the oil tank, was hinged to allow access to the rear wheel and drive chain. Amal Monobloc carburetors improved starting and performance. A unique center stand was operated by a lever accessible from the seat and the lower front fender included an emergency front stand to allow roadside removal of the front wheel.
Delays in the construction of the fiberglass components from subcontractors held up delivery of the first production bikes until spring 1955, but eventually, some 200 of the enclosed models were built.
The target market at the time, British citizens finally recovering their financial footing after the Second World War, was hungry for a high end luxury touring bike. The firm thought they had a viable formula, but at that precise moment, a slew of very affordable small cars flooded the market and Vincent’s accountants found themselves in the unenviable position of knowing they were losing money on every Black Knight the company sold.
It’s all about the money, and that meant the model and the marque were out of production as of December 1955.
Not A Black Prince
The Black Knight can easily be mistaken for the very similar Black Prince. A cursory examination would show that externally, both models were nearly identical. The noticeable difference is in the emblem on the front and rear fenders and wheel covers. How do you tell the difference? An emblem on a Black Knight shows a Vincent scroll, with the model name (Black Knight or Black Prince) below the scroll and a unique graphic just above the scroll.
For the Black Knight, the graphic is an axe; for the Black Prince, a helmet.
Armed with unmatched engineering talent for the times, Vincent spared no expense constructing a 998cc V-Twin that was capable of 55bhp. Philip Vincent was an engineering child prodigy and he wasn’t afraid to sing his own praises.
“I myself have ever been an inventive type of designer,” Designer Philip Vincent once said. “I always seeking to incorporate details which represent a worthwhile and big advance over previous designs.”
“There is a fundamental difference, however, between the old Vincents and the new breed of superbikes. If you rode the Black Shadow at top speed for any length of time, you would almost certainly die. That is why there are not many life members of the Vincent Black Shadow Society.”
- Hunter S Thompson
The guts of every Vincent Twin (and the company did make a single cylinder engine) is an extremely pretty and functional 50 degree V-Twin. To keep the engine light and compact the valves were opened by extremely short push-rods which eschewed the more common overhead cam design which has become the standard on modern engines. The push-rod meant the valves are engaged part way down their stems placing the rockers and springs as far as possible from the heat generated by the cylinder head. This design delivered a powerplant which ran with a smooth, near silent action and minimal vibration.
The 998cc Vincent Twin produced 55 BHP. That may not sound like much given the output of modern engines of that displacement, but it was far and away more powerful than contemporary machines. A brand new Vincent could comfortably operated from 30 to 120 mph in top gear, and that made it the class of the times.
Highly advance engineering didn’t end with the powerplant on the Black Knight. Two drum brakes on each wheel and hydraulically damped girder forks were married to a servo clutch to make the suspension and transmission of the bike cutting edge. The clutch itself represented the sophisticated design of the times.
Other design features pushed the edge of the envelope and prefigured ideas which are still being used today on the most sophisticated models. The engine was a stressed member of the frame, and that might remind your of ideas which are still in use. The top spine of the frame contained 6 pints of oil, and a triangulated swinging arm was projected through the rear of the crankcase. The result? An extremely short wheelbase on what was for the times a very, very big bike.
During a period when the best and brightest designs were capable of 100 mph if they were lovingly tuned, stripped and tweaked to perfection, the Black Knight and Black Shadow reached that speed without breaking and sweat and ran there all day long. The sportier version of the Rapide, the Black Shadow, was essentially the first ‘Superbike,’ and capable of 125 mph straight out of the crate. A Vincent Lightning, expertly tuned, took Rollie Free to an astounding 150 mph during runs across the Bonneville Salt Flats.
What did all this design and performance cost?
In 1951, a new Black Shadow would set you back just over $600. Consider that you could have a perfectly serviceable and speedy BSA Gold Star for just under that at around $380. It doesn’t, given current prices, sound like a lot of money, but consider this: the average British wage for most workers was something like $10 a week, and at that rate, you would have had to pile up your check for over a year to buy a new Vincent. That made a Vincent worth something like $40,000 in today’s money, and that’s not chump change…
Did all this styling cachet and blinding performance ultimately work? It did. A Black Knight sold at auction through Bonham’s not that long ago for a choke-worthy $59,000.
If that figure doesn’t deter you from still seriously coveting a Black Knight, how about putting together a suitcase stuffed with cash and building one brand new from a kit? You read that right, if you have the financial means and the determination, you can put together a brand-new Vincent Shadow, or Rapide with parts from the Vincent Owners’ Club parts department. They have damn near everything you’ll need in stock.