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.


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

Related models: