AJS Model 20 500 (1948-61)

The AJS Model 20 500 (1948-61) was a four-stroke, parallel twin-cylinder motorcycle with a capacity of 498cc and a compression ratio of 7.3:1. It featured 2 valves per cylinder, a 3-saved plain bearing/roller bearing crankshaft, and a Lucas magneto ignition with kick starting. The clutch was a multi-plate dry Burman and the transmission was 4-speed with a chain final drive. The frame was a single cradle with hydraulic telescopic fork front suspension and dual shocks in the rear. The brakes were drums both front and rear, and it had 3.25-18 tyres on both the front and rear. The fuel capacity was 17 L / 4.5 US gal and the top speed was 150 km/h / 93 mph. The bike weighed 178 kg / 392 lbs and had an oil capacity of 2.5 L / 5.3 US pt. It was a popular motorcycle during its production years.

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Technical specifications:

Make Model: AJS Model 20 500

Year: 1948 – 61

Engine: Four stroke, parallel twin cylinder, OHV. 2 valve per cylinder, Crankshaft: 3-saved plain bearing / roller bearing

Capacity: 498 cc / 30.4 cu in

Bore x Stroke: 66 x 72.8 mm

Compression Ratio: 7.3:1

Cooling System: Air cooled

Oil Capacity: 2.5 L / 5.3 US pt

Induction: Carburetor

Ignition: Lucas magneto, K2F

Spark plug: KLG FE80, 14 mm thread

Starting: Kick

Clutch: Multi Plate (dry, Burman)

Max Power: 21.6 kW / 29 hp

Transmission: 4 Speed

Final Drive: Chain

Frame: Single cradle

Front Suspension: Hydraulic telescopic fork

Rear Suspension: Dual chocks

Front Brakes: Drum

Rear Brakes: Drum

Front Tyre: 3.25 -18

Rear Tyre: 3.25 -18

Weight: 178 kg / 392 lbs

Fuel Capacity: 17 L / 4.5 US gal

Top Speed: 150 km/h / 93 mph