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AJS Model 20 500
1958Allround

AJS Model 20 500

Key specifications

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

Overview

### AJS Model 20 500: The Quintessential All-Rounder Introducing the 1958 AJS Model 20 500, a motorcycle that stands as a testament to the British engineering prowess of its era. Marketed as an all-rounder, the Model 20 500 was designed to cater to a wide range of riders, from the casual commuter to the weekend adventurer. With its classic styling and robust construction, this bike embodies the spirit of freedom and exploration that motorcycling enthusiasts crave. It’s not just a motorcycle; it's an invitation to the open road, promising versatility and reliability in equal measure. At the heart of the AJS Model 20 500 lies a spirited 498cc twin-cylinder, four-stroke engine that delivers a respectable 20 horsepower at 6800 RPM. This powerplant propels the motorcycle to a top speed of 137 km/h (85 mph), making it capable of both spirited rides and leisurely cruises. The engine's 7.0:1 compression ratio and efficient carburettor fuel system ensure responsive acceleration and smooth operation, while the wet multiplate clutch allows for seamless gear shifts. With a lightweight chassis tipping the scales at just 178 kg (392.4 lbs), the Model 20 500 offers an engaging riding experience, whether navigating city streets or winding country roads. The engineering of the AJS Model 20 500 is complemented by its thoughtful design features. The single cradle frame provides a sturdy foundation, while the telescopic front suspension and twin shock rear suspension work harmoniously to deliver a smooth ride over varying terrain. The drum brakes—both front and rear—offer reliable stopping power, a must for any rider seeking confidence on the road. Additionally, the bike's kick starter adds a nostalgic touch, connecting riders to the roots of motorcycling. Fueling this classic machine is a 13.5-litre tank, ensuring ample range for those long rides where adventure beckons. ####

Pros

    Cons

    • Classic Design: Timeless aesthetics that appeal to vintage motorcycle enthusiasts.
    • Versatile Performance: Capable of handling a variety of riding conditions with ease.
    • Lightweight Build: The low weight enhances maneuverability and rider control.
    • Limited Power Output: While adequate for casual rides, the power may feel lackluster for performance enthusiasts.
    • Drum Brakes: While functional, they may not provide the same stopping power as modern disc brakes.
    • Kick Starter Only: The absence of an electric starter can be inconvenient for some riders, especially in cold weather.

    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
    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)
    Power Weight Ratio
    0.1124 HP/kg
    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