AJS Motorcycles

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AJS 1934 Model 12 250cc

Model 34-12 2.48 h.p. "BIG PORT" O.H.V.

ENGINE - Of A.J.S." design and manufacture. Single-cylinder, overhead valves. Bore 65 m.m. Stroke 75 m.m. Capacity 248 c.c. Adjustable mechanical lubrication by gear-driven pump made integral with the magneto chain cover. Compression ratio 6.5 to 1. Single-port down draught detachable cylinder head of efficient design, duplex valve springs, Duralumin rocker arms, tappet tubes and small end bush. Aluminium alloy piston with four rings, fully floating gudgeon pin, roller bearing big end, single row ball bearings to timing-side mainshaft and double row ball bearings to driving side mainshaft. Totally enclosed exhaust valve lifter mechanism and tappet adjustment. Inspection disc on magneto chain cover for inspecting chain tension. Vernier setting device for ignition timing.

GEAR BOX - Four-speed gear made, to "A.J.S." design. Ratios 5.8, 7.73, 11.36 and 17.22 to 1. Enclosed foot starter mechanism. Hand or foot operated gear-change optional.

CLUTCH - Simp1e single plate clutch with hand control of light tension. Push rod and control cable adjuster provided.

FRAME - Stiffened Frame with torque stays from engine plates to rear axle.

TYRES - 26 in. x 3.5 in. Studded Cord Tyres.

WHEEL HUBS - Adjustable taper roller bearings to both wheels.

CARBURETTOR - "Amal" needle-type with throttle stop and twist grip control.

HANDLEBARS - Adjustable semi-sports pattern with controls made integral. Black enamel finish and chromium plated levers.

FRONT FORKS - Centre barrel spring type with adjustable spindles and hand adjustable shock absorber. Hand adjusted multi-plate steering damper.

FOOTRESTS - Adjustable to wide range position with thick rubber covering.

SADDLE - " Lycett " flexible top, adjustable in all directions.

BRAKES - InternaI expanding front and rear, both 5½ in. diameter, fitted with hand adjusters, dust and water excluders. Powerful and progressive in action.

TRANSMISSION - "Renold" chain, size ½ in. x .305 in. Primary drive running in oil bath. Efficient shock absorber fitted to engine shaft, lubricated by oil bath. Rear chain adequately protected by top half chain cover.

MUDGUARDS - Dome section. Rear, with hinged back portion to facilitate wheel removal.

STAND - Easily operated centre stand.

EQUIPMENT - Complete kit of tools including grease gun and tyre inflator.

PETROL TANK - Finish : Usual "A.J.S." black and gold. Capacity 1 ¾ gallons. Provision in top for flush fitting instrument panel, quick action filler cap.

OIL TANK - Capacity 3 ½ pints. Quick action filler cap.

EXHAUST SYSTEM - As illustrated, or the normal down-swept exhaust system with standard pattern silencer optional.

PRICE - To Standard Specification £42-10-10

From the 1934 AJS Catalogue

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