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AJS Model 20 500
1957Allround

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

Introducing the quintessential classic motorcycle of the late 1950s, the 1957 AJS Model 20 500, a versatile all-rounder that elegantly marries vintage charm and practical performance. As AJS transitioned into the era of modern motorcycling, the Model 20 stood out with its sleek design and robust build, appealing to both seasoned riders and newcomers alike. With its impressive lineage, the Model 20 is not just a motorcycle; it's a piece of history that resonates with those who appreciate the artistry of engineering and the thrill of the ride. At the heart of the AJS Model 20 500 lies a capable 498cc twin-cylinder, four-stroke engine that generates an admirable 20 horsepower at 6,800 RPM. This power translates into a top speed of 85.1 mph, making it an exhilarating choice for both daily commuting and weekend adventures. The engine's 7.0:1 compression ratio and air-cooling system showcase its reliability, while the wet multiplate clutch ensures smooth engagement and transitions. Riders will appreciate the responsive handling provided by the telescopic front suspension and twin shock rear, making every ride a delightful experience, whether navigating city streets or cruising on open highways. The AJS Model 20 is not just about performance; it also boasts a range of features that enhance the riding experience. The single cradle frame offers stability and strength, while the drum brakes on both the front and rear provide dependable stopping power. With a fuel capacity of 13.5 liters, this motorcycle is designed for longer journeys, allowing enthusiasts to enjoy the open road without frequent stops. Notably, the kick starter adds an element of nostalgia and simplicity, connecting riders with the classic spirit of motorcycling. **

Pros

  • Classic Aesthetic: The 1957 AJS Model 20's design exudes vintage charm, appealing to collectors and enthusiasts alike.
  • Dependable Performance: The robust engine delivers a satisfying mix of power and efficiency, perfect for various riding conditions.
  • Comfortable Ride: The combination of telescopic front forks and dual rear shocks ensures a smooth and enjoyable ride.

Cons

  • Limited Power: With only 20 HP, it may struggle to keep up with modern traffic on faster highways.
  • Drum Brakes: The outdated drum brake system may not provide the same stopping power and responsiveness as contemporary disc brakes.
  • Kick Start Only: The absence of an electric starter may deter some riders who prefer the convenience of modern starting systems.

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
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