Douglas Motorcycles

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Douglas 1925 OW 346cc

The OW/25 model is perhaps the most fascinating sporting 2¾ h.p. motor cycle on the roads to-day. The wonderful little vibrationless twin-opposed, overhead-valve engine is remarkably efficient, having a useful working range of revolutions between 1,000 and 6,000 per minute.

ENGINE - 57 mm. x 68 mm., capacity 346 c.c. Deep ribbed, cast-iron cylinder barrels fitted with detachable cylinder beads and unbreakable overhead valves. The cylinder heads carry a special device for lubricating the overhead rockers. The valves are fitted with double-valve springs. PISTON - The pistons are of special cast iron, having a tensile strength of 18 tons,

CONNECTING RODS - Of special alloy steel, H section, the big end being hardened and ground to take the roller bearings, the little end being fitted with a gun-metal bush, provision being made for lubrication of the gudgeon pin by a large slot milled on the top of the little end.

CRANKSHAFT - Of special alloy steel, hardened and ground, fitted with roller bearings of the cage type. The crankshaft is very short and stocky, which thus eliminates all tendency to whip.

CAMSHAFT - Of special alloy steel.

INDUCTION PIPE - Is fitted with large exhaust heated jacket.

KICK-STARTER - Is incorporated in the timing chest of the engine, being totally enclosed.

CARBURETTER - Amac or Douglas semi-automatic type, according to supplies.

IGNITION - By E.I.C. or other British make of magneto. Special provision is made for removing the magneto without interfering with the timing - this system being patented.

K.L.G. sparking plugs are fitted to this machine.

LUBRICATION - Semi-automatic by spring returned hand pump, through adjustable sight feed fitted on petrol tank, the oil passing through to the front cylinder, after which lubrication is automatic. We recommend for this machine WAKEFIELD'S Castrol X.L.

Douglas won the Durban-Johannesburg Marathon race, distance 430 miles

GEAR BOX - Douglas patented, three-speed special oil retaining gear box is used.

CLUTCH - Douglas, inherently balanced, single-plate flywheel clutch is fitted.

HAND CONTROL - The action is exceedingly simple, the spring pressure being very light and docs not tire the operator during long spells in traffic.

FRONT FORKS - Of special pattern fitted with one piece links, giving great rigidity. Lubrication of the forks is by means of pressure grease gun system.

FRAME - Of new duplex Douglas design and built of weldless steel tubing, giving a very low centre of gravity and riding position, making the machine practically immune from skidding.

PETROL TANK - Of large capacity, holding 2 1/2 gallons and 1/2 gallon of oil.

SADDLE - Douglas patent saddle, giving a low riding position.

TYRES - 26x2 1/4 or 650 x 65 first-class make.

FOOTBOARD - Cast aluminium with heavy rubber studs.

MUDGUARDS - Strong, deep section. Douglas pattern guards, giving ample clearance between the tyre and guard to prevent clogging from mud, etc

CARRIER - Of tubular construction, carrying two metal pannier tool boxes of robust construction.

BRAKES - Both front and back brakes are fitted with " V " shoes, operating in special brake drums, the brake shoes being arranged by means of a patented mechanism to apply the braking pressure radially.

FINISH - Tank is highly burnished in aluminium with royal blue panels and varnished with petrol proof varnish. The frame and all enamelled parts are treated by anti-rust process and afterwards are enamelled three coats of the finest black.

PETROL AND OIL CONSUMPTION - Touring conditions, 100 m.p.g. petrol ; 1,200 m.p.g. oil.

STANDARD EQUIPMENT - Complete kit of tools, pump, and oil or grease gun.

Electrical Equipment for this model £10 extra.

We reserve the right to amend this specification without notice.

A specialty light Sporting sidecar, exceptionally strung, is made to fit the O.W. machine, which we recommend for high speed touring. This sidecar can also be fitted to the O.B. model.

A windscreen, mounted on a cast aluminium base, together with a mudguard of ample dimensions, provides excellent protection from mud and water.


Nett Weight .. 2 cwt, 0 qrs. 10 lbs.

Gross ......4 cwt, 1qrs. 10 lbs.

Measurements... 88in. x 21in. x 42in.

Price in U.K. - £65 Solo. £81 Sidecar Outfit.

Douglas gained the Spanish Twelve Hours race, 466 miles, making fastest lap and record for the course.

If you have a query about Douglas 1925 OW 346cc please contact us