TRIALLING ON THE 'BULLDOG'

By Bill Snelling:

When I was first took residence here on the Isle of Man, I was loaned one of Bob Thomas' fore-and-aft Douglases [Douglii?], to compete in a V.M.C.C. Trial. A 'Light 500' model (or 'Bulldog', see photo of the standard model below), Bob used 19" tyres - the rear so old it stood up with no air in. To increase the ground clearance from barely nil to just over nil, the engine was raised in the frame by an alloy plate.
Trials held early in the year posed a problem not normally associated with a finely-honed competition mount, as the single carburetor fed both cylinders via a very long manifold. You could start it easy enough, but five minutes later it died: the whole manifold was covered in ice. After a few minutes, the ice dispersed and it would start again...sometimes you had to repeat this ritual half a dozen times before the all-cast-iron engine warmed enough to keep running!

A not uncommon occurrence when riding this machine was to unwittingly shed the oil feed pipe. I once charged at a section, when the engine seized solid and rapidly deposited me in the mud. Thank heavens for cast-iron pistons; we relocated the pipe, took the plugs out and pushed the Dougie around a bit, refitted the plugs and she ran like a bird the rest of the day.
Riding through water posed a unique problem (or two) - you could not slip the clutch. Two things would happen; first, it hydrauliced and forward motion ceased. And as the petrol tank was very narrow, the big external flywheel scooped up water (and/or mud) and flung it upwards; you suddenly lost sight in your left eye and developed an uncomfortable feeling in an area of the body which sounds like an amalgam of the words testament and icicle!

Not the ideal Trials machine, but it gave me many years of fun; Thanks Bob.

[And thanks Bill!
Bill Snelling is a powerhouse of Isle of Man motorcycle racing history, and his publishing imprint Amulree Publications has produced such titles as 'Aurora to Ariel', 'The History of the Isle of Man Clubman's T.T. Races, 1947-56', etc. He also owns the rights to the extensive S.R. Keig collection of photographs, and runs the FoTTofinders photographic service for anyone looking for particular riders/motorcycles which have raced at the Island, and many I.S.D.Ts; his database includes around 250,000 images!]

THEN AND NOW

The evocative sepia photo shows Graham Browne racing his '25 TT Douglas at Brooklands. The color photo shows the same bike at Brooklands, where it now lives, in original condition, after being left to the museum by Mr Browne himself, who retained ownership throughout his life. A remarkable partnership, by any standard.
The bike is very interesting, as it has a cast aluminum sump beneath the engine, and a proper oil pump circulating the oil under pressure. Only the pukka works racing Douggies had this feature; otherwise the bike looks fairly standard compared to, say, my own prosaic machines! A look at the engine close-up reveals the fins of the sump beneath the engine, and an oil pressure gauge on top of the airbox (another unique feature of the Douglas, added by Freddie Dixon). The oil pump proper is visible at the center of the sump; it's driven by a shaft-and- bevel arrangement inside the airbox.

The induction manifolds are wrapped with friction tape to keep them from freezing up when alcohol fuel is used. The engine never gets particularly warm when using alcohol, as it burns much cooler than gasoline. If the manifolds freeze, the carbs can freeze as well and jam the throttle wide open during a race - exciting but best avoided. I experienced manifold frost on the BMW R63 mentioned in an earlier post; the pipes were almost a foot long, and gained a haze of moisture as on a cold drink, almost immediately after starting the engine.

MORE VINTAGE RACING DOUGLAS

Not much is heard these days about Douglas motorcycles, but their racing machinery in the 20's was among the best and most innovative in the world. They built the first 500cc motorcycle to record 100mph in Britian (1921!), won many Isle of Man TT's, and developed the first disc brakes. Shown in this photo are two 'RA' models, after a race on a banked circuit. The 'RA' was so named after the Research Association, a group attempting to advance motorcycle technical development, and which created the disc brakes on these two machines. Hydraulic calipers, as used today on discs, weren't developed yet (not until the late 30's), so they used mechanical leverage on a steel 'shoe', which pressed on the disc, which was made of friction material - the opposite of today. Still, there were much better brakes than the 'dummy rim' type on my motorcycle - basically a flimsy secondary wheel rim attached to the spokes, onto which a shoe of friction material is pressed (a design cribbed from horse-drawn carriages!).
These RA's would have run on alcohol, and in full flight would have probably hit 110 mph; this is 1924. Amazingly, these 1920's racing Douggies are still used in competition today, albeit in vintage sprint meetings, where they win regularly against bikes from the 60's and 70's, pulling 1/4 mile times in the 11 sec range.
I love the old one-marque sweaters which were fashionable in the 'teens and twenties, probably knit by a sympathetic mother. If you look closely at the lettering on the right rear mechanic, it's a different font from all the other 'Douglas'. Also, the American rider is wearing a football helmet, which was a common sight on board track and dirt track racing in the USA.