‘SO MUCH MORE THAN JUST AN ENGINE’
Though its top speed grabbed headlines, the Black Shadow’s handling was equally ahead of its time. CB’S Mike Armitage explores the chassis and riding experience
Vincent’s big V-twin pushed boundaries of straight-line performance, but also set the benchmark for chassis design. With its engine as a stressed member, the first rear-end that we now recognise as a swingarm and eye-opening adjustability, the Black Shadow shaped modern motorcycles.
Swingarm rear suspension had been dabbled with pretty much since bikes were invented – America’s Thomas Motor Company had a triangulated design on their Auto-bi as early as 1903. But though others tried swin garms and springs, Vincent’s patented cantilever swingarm first seen on the Meteor and Comet singles established a layout since used by almost every major brand. With damped suspension units added on the Rapide, they set the blueprint for the cantilever mono shocks on today’s bikes.
The unit-construction engine for the 1946 B-series Rapide was as a load-bearing part of the chassis, so Vincent didn’t need a normal frame. A simple spine fixed the steering head to the engine and doubled as the oil tank, the swingarm hanging from the back of the engine. Ducati’s ‘monocoque’ 1199 Panigale looked radical when it was launched in 2012, yet was replicating Vincent’s visions of 70 years before.
Black Shadow chassis design went further, with the friction-controlled girder fork replaced with the Girdraulic set-up. With springs running alongside the fork blades and a central hydraulic damper, the firm’s new 125mph machine had proper ride quality when many British bikes still had rigid frames. There was more: geometry could be altered, and ’bar, footpeg, levers and seat were adjustable. This was cuttingedge in 1948 – and is still beyond most bikes now.
Ride a Black Shadow today and it’s hard to think it’s a 70-year-old design. Utterly stable with a very ‘together’ feel, its geometry and low weight give wonderful low-speed agility. Great steering lock, too. Up at modern road speeds the bike is unflustered and remains simple to handle. And the motor plays a part: the famous V-twin offers lazy torque for easy progress and is wonderfully relaxed in the middle of its range, with a light twistgrip and great sense of connection between your right hand and the crank.
And yes, it’s still brisk. If it hits 60mph in second gear, schoolboy logic means 120mph in fourth…
Simple, yet very clever at the same time