ENGINE: Double high camshaft O.H.V. Vertical Twin. Bore : 63 mm.; Stroke : 80 mm.; Capacity 498 cc. Special high compression alloy slipper pistons; polished hemi-spherical combustion chambers and ports ; "H" section connecting rods in R.R. 56 Hiduminium alloy with Triumph patented big ends. Triumph patented crankshaft incorporating integral balance weights and with centrally disposed flywheel. All moving parts polished. Totally enclosed valve gear. Duplex Aero quality valve springs.
Dry-sump lubrication system by means of a pair of plunger type pumps with positive lead to valve gear. Separate oil tank - one gallon capacity - with large quick action filler. Cylinder head and barrel in closely grained cast iron. (Bronze cylinder head to special order, £5 extra). Crankcase, of great rigidity in high tensile aluminium alloy. Large bore Amal carburetter and induction pipe. Each engine individually tested on Heenan and Froude brake, stripped and re-assembled by skilled mechanics. Test Card signed by Chief Tester, supplied
PETROL TANK: Of Triumph Registered design giving a capacity of four gallons and incorporating recesses in the sides for the knee grips. Metal braided flexible petrol pipes and two large bore taps fitted. SILENCERS: Of the open megaphone type but with quickly detachable end portion incorporating baffles and tail pipe.
FRAME : Triumph cradle type with straight down tube of tapered formation. This new frame provides superb roadholding and steering of a quality fully in keeping with the high performance of which the engine is capable.
GENERAL: For further particulars see specification of "Speed Twin" on page 2.
FINISH: Petrol Tank: Chromium plate with silver sheen panels lined out in blue.
Mudguards : Silver sheen with black centre strip.
Wheels : Chromium plated rims with silver sheen centres lined out in blue ; chromium plated spokes.
Frame : Finest quality black enamel.
All aluminium parts highly polished.
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