ENGINE - 72x85 mm. (347 c.c.). O.H.V. Two-port (NH.2) or Single-port (NH I) optional. Specially bench-tested and capable of being tuned to speeds exceeding 80 m.p.h. Totally enclosed valve springs. Valve guides automatically lubricated. Ground and highly polished ports. 14 mm. sparking plug. Heavily ribbed crankcase. Polished forged steel flywheels. Ball bearings on both sides of mainshaft. Double roller bearing big-end. Special polished alloy steel con-rod. A medium compression piston is fitted as standard. A high compression piston, giving a ratio of 7.5 to I (suitable for 50 50 Petrol/Benzole only) can be fitted to special order, without extra charge.
LUBRICATION - Dry sump system, employing dual plunger pumps and -gallon capacity separate oil tank.
CARBURETTER - Large bore, down-draught Amal. Petroflex supply pipe.
GEARBOX - Four-speed. Foot control.
TRANSMISSION - Engine shaft shock absorber. Polished aluminium oil bath chain case. Rear chain fully protected and automatically lubricated.
EXHAUST SYSTEM
Two-port: Silencer: As illustrated.
Pipes: Upswept with leg guards or low level to special order.
Single-port: Silencer: As illustrated.
Pipe: upswept with leg guard or low level to special order.
WHEELS - Dunlop tyres. 26x3.25, studded rear; 26x3, ribbed front. Chromium brake plates. Chromium rims. Red centres.
MUDGUARDS - Robust ribbed section steel guards, as illustrated. Tail of rear guard hinged to facilitate wheel removal.
TANK - All-steel saddle type, with instrument panel. 2½-gallon capacity. Superbly finished Chromium and Red, lined Gold.