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AJS Model 20 500
1952Allround

AJS Model 20 500

Key specifications

Engine
498 cc
Power
20 HP
Weight
178 kg
Fuel type
petrol
Fuel capacity
3.6 L
Transmission
4-speed
Front brakes
Expanding brake (drum brake)
Rear brakes
Expanding brake (drum brake)

Overview

### Introducing the 1952 AJS Model 20 500 The 1952 AJS Model 20 500 stands as an iconic representation of post-war British motorcycling, blending classic design with reliable performance. Positioned in the allround category, this motorcycle appeals to enthusiasts seeking a versatile ride capable of handling a variety of terrains and purposes. With its striking lines and distinctive styling, the Model 20 captures the essence of mid-century motorcycling, making it a cherished piece of history for collectors and riders alike. ### Engine Performance and Riding Characteristics Beneath the elegant exterior lies a robust 498 cc twin-cylinder, four-stroke engine that delivers a spirited 20 horsepower at 6,800 RPM. This power allows the Model 20 to reach a top speed of 137 km/h (85.1 mph), ensuring an exhilarating ride on both city streets and country roads. The engine's 7.0:1 compression ratio, combined with a carburettor fuel system and magneto ignition, provides a reliable and responsive throttle response, making it an enjoyable motorcycle to ride. The 4-speed gearbox, coupled with a chain final drive, delivers smooth shifts and optimal acceleration, while the wet multiplate clutch enhances control during various riding conditions. ### Key Features and Technology The AJS Model 20 500 is engineered with thoughtful features that cater to both comfort and performance. Its single cradle frame offers a sturdy foundation, while telescopic front suspension and twin shock rear suspension contribute to a smooth ride over uneven surfaces. The motorcycle is equipped with drum brakes at both the front and rear, providing reliable stopping power typical of its era. With a fuel capacity of 13.5 liters, riders can enjoy longer journeys without frequent stops, while its manageable weight of 178 kg ensures an agile riding experience. The kick starter adds a touch of classic charm, reminding riders of the traditional methods of firing up a beloved machine. ###

Pros

    Cons

    • Classic Aesthetic: The Model 20's vintage design and styling make it a head-turner and a great addition to any classic motorcycle collection.
    • Balanced Performance: With a top speed of 137 km/h and adequate power output, it strikes a fine balance between performance and usability for various riding needs.
    • Comfortable Ride: The combination of a well-designed frame and effective suspension makes for a comfortable ride on diverse terrains.
    • Limited Power: While 20 HP is sufficient for casual riding, it may not satisfy those seeking high-performance thrills from their motorcycle.
    • Drum Brakes: The drum brake system, while reliable, may lack the stopping power and responsiveness offered by modern disc brakes.
    • Kick Start Only: The absence of an electric starter can be a hassle for some riders, especially in challenging conditions or during cold starts.

    Technical details

    Source specification data

    Make
    AJS
    Model
    Model 20 500
    Category
    Allround
    Starter
    Kick
    Power
    20.00 HP (14.6 kW)) @ 6800 RPM
    Clutch
    Wet multiplate
    Gearbox
    4-speed
    Ignition
    Magneto
    Top Speed
    137.0 km/h (85.1 mph)
    Fuel System
    Carburettor
    Bore X Stroke
    66.0 x 72.8 mm (2.6 x 2.9 inches)
    Compression
    7.0:1
    Displacement
    498.00 ccm (30.39 cubic inches)
    Cooling System
    Air
    Engine Details
    Twin, four-stroke
    Transmission Type Final Drive
    Chain
    Dry Weight
    178.0 kg (392.4 pounds)
    Fuel Capacity
    13.50 litres (3.57 gallons)
    Overall Width
    710 mm (28.0 inches)
    Overall Height
    1,050 mm (41.3 inches)
    Overall Length
    2,190 mm (86.2 inches)
    Power Weight Ratio
    0.1124 HP/kg
    Seat
    Dual
    Wheels
    Spoked
    Rear Tyre
    3.25-19
    Frame Type
    Single cradle
    Front Tyre
    3.25-19
    Rear Brakes
    Expanding brake (drum brake)
    Front Brakes
    Expanding brake (drum brake)
    Rear Suspension
    Twin shock
    Front Suspension
    Telescopic