Triumph Motorcycles

Triumph 1939 Speed Twin

ENGINE: Bore and stroke 63 mm. by 80 mm. 498 c.c., O.H.V., double high camshaft vertical Twin unit with deeply finned cylinder barrel. All-gear drive to camshafts and magdyno. Totally enclosed valves with accessible tappet adjustment. Designed to give sustained high power output with even slow speed torque and mechanical silence.

CONNECTING RODS : "H" Section in R.R. 56 Hiduminium Alloy, with Triumph patented big ends.

CRANKCASE AND TIMING GEAR: High tensile, aluminium alloy, crankcase of great rigidity. Polished cast aluminium timing cover incorporating oil-release valve.

CRANKSHAFT: Triumph patented with centrally disposed flywheel, mounted on heavy duty ball bearings. New engine shaft shock absorber incorporating modified cam contours, giving sweeter transmission, particularly at low speeds.

VALVE SPRINGS : Duplex Aero quality.

LUBRICATION: Full dry sump system, incorporating accessible plunger type pumps with positive feed to big ends and enclosed overhead valve gear. Long wear and mechanical silence. Oil gauge in instrument panel.

CARBURETTER: Amal. Triumph patented quick-action twist-grip throttle control with click action.

PETROL TANK: All-steel welded, combining shapely streamline contour with 3t-galls. capacity. Die-cast, all-metal, permanent nameplate. Flush rubber mounted instrument panel of moulded construction, carrying oil gauge, ammeter, switch and new and exclusive external pane! light Quick-opening filler cap.

OIL TANK: All-steel welded, with accessible filters, drain plug and separate vent. Capacity ¾ gall.

FRAME : Brazed full cradle type, soundly constructed from tubes of finest alloy steel, combining immense strength with low weight. Large diameter tapered front down tube. Comfortable riding position with high standard of road-holding.

FRONT FORKS : Exceptionally light, but strong. Taper tube girder type incorporating rebound dampers with hand adjustment on the lower bridge.

GEARBOX AND CLUTCH: Four-speed Triumph patented design and manufacture. Gears and shafts of hardened nickel chrome steel, finished to the highest possible standards of accuracy and precision. Patented positive stop foot change - fully enclosed. Short pedal movement giving delicacy of control with completely positive action. Large diameter multi-plate clutch with enclosed operating gear, light in operation with smooth engagement; accessible adjustment. Lubrication by engine oil.

TRANSMISSION: Primary chain running in polished cast aluminium oil-bath chain case of streamline design. Rear chain positively lubricated by feed from primary chain case.

BRAKES : Triumph 7 in. diameter brakes with special alloy detachable ribbed drums and extra wide shoes, New brake lining material giving powerful and smooth braking with long life. Finger adjustment for both brakes, with front adjuster accessible from saddle.

SADDLE : De Luxe soft lop type, adjustable for height.

HANDLEBAR: New Triumph design with modified bend, resiliently mounted, eliminating fatigue and shocks, and giving great riding comfort and controllability. Control levers grouped and adjustable to suit individual requirements. Lone type brake and clutch levers.

MUDGUARDS: Of adequate 'width with streamline section stays. Detachable tail piece to facilitate rear wheel removal. New Triumph patented front number plate with chromium edge and motif. Streamlined rear number plate (regd. design) with rear lamp mounted centrally where it is adequately protected against risk of damage.

WHEELS AND TYRES : Latest Triumph wheels with spokes of approximately equal length, taking braking and transmission stresses. Dunlop tyres. Front 26" x 3' ribbed, rear 26' x 3.50" speed universal.

TOOLBOX: Shapely all-steel construction, of large capacity, with rubber sealed lid ensuring protection against water. Complete set of good quality tools and grease gun.

FINISH AND EQUIPMENT: Finished in Amaranth (Dark) Red. Petrol tank in chromium plate with Amaranth Red panels, lined out in Gold. New design of knee grips combining maximum comfort with security at high speeds. Spokes and rims chromium plated, with Amaranth Red centres lined out in Gold. Lucas 6-volt magdyno lighting with voltage control. Lucas 8" diameter chromium plated, anti-glare headlamp. Altette horn, chromium plated downswept exhaust pipes. All aluminium parts smooth and highly polished, and both chromium plate and enamel of the highest quality. All bolts Cadmium plated.

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