Photo ou archives : F-M. Dumas
6406
PHELON & MOORE (PANTHER)
500cc Prototype -1924
Too far ahead of his time
From his first ABC in 1913 to his final project in 1955, via his famous "oil-boiler" engines of the 1920s, engineer Granville Bradshaw was an often-visionary genius who was also very out of touch with reality.
Too Far Ahead of Their Time
His creations, too far ahead of their time and taking only the slightest notice of the difficulties involved in their realization, provoked ABC's failure and nearly brought the same fate to Panther - alias Phelon & Moore - for whom he designed, in 1926, the remarkable but over-ambitious Panthette V-twin.
A Fine Beginning
Bradshaw joined Panther in 1923 as chief of design. He created a model that perpetuated P & M's traditional image. Since 1901, P & M had been building motorcycles with a steeply-inclined single-cylinder that replaced the front downtube of the frame. Respecting the product brief for once, Bradshaw created a bike that was as modern as it was exceptional, launched at the 1924 London Show. The long-stroke engine was in the specified Panther position and - in those days of fully-exposed valve gear - innovated by concealing its pushrods in a large-diameter chromed tube that gave the impression that the bike had a shaft-driven overhead camshaft. The oil reservoir was incorporated in the crankcase beneath the engine, and the oddly angled intake manifold was intended to speed up gas flow into the combustion chamber. The latter touch was soon dropped by P & M (but later adopted by Norton). The Panther-Bradshaw became a British success
story. This model, modified over the years and bored out to 650cc, survived until the
marque vanished in 1966.
SPECIFICATIONS
Engine: 499cc (84x90mm) air-cooled inclined single-cylinder four-stroke; magneto ignition
Valves: overhead
Fuel System: carburetor
Transmission: 3-speed hand-shift, chain final drive
Suspension: leading-link girder forks (front); rigid (rear)
Brakes: dummy belt rim (front & rear)
Wheels: wire clincher (front & rear)
This rare period photograph shows the prototype 1924 Panther at the P & M factory before its debut at the London Motorcycle Show.