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AJS Model 31 650 Swift
1964Allround

AJS Model 31 650 Swift

Key specifications

Engine
646 cc
Power
31 HP
Weight
176 kg
Fuel type
petrol
Fuel capacity
4.2 L
Front brakes
Expanding brake (drum brake)
Rear brakes
Expanding brake (drum brake)

Overview

### Introduction to the 1964 AJS Model 31 650 Swift The 1964 AJS Model 31 650 Swift stands as a distinguished figure in the annals of British motorcycling history. Positioned in the all-round category, this classic motorcycle encapsulates the essence of mid-20th-century engineering, merging practical performance with timeless aesthetics. AJS, renowned for their innovative designs and robust builds, crafted the Model 31 Swift to cater to riders seeking versatility, whether for daily commutes or leisurely weekend rides. With its striking lines and vintage charm, this motorcycle is not just a mode of transportation; it’s a piece of art that evokes the spirit of freedom and adventure. ### Engine Performance and Riding Characteristics At the heart of the AJS Model 31 Swift lies a powerful V2, four-stroke engine with a displacement of 646 cc, generating an impressive 31.40 HP at 6000 RPM. This robust powerplant provides a delightful blend of torque and acceleration, ensuring that riders experience a satisfying rush as they twist the throttle. With a compression ratio of 7.5:1 and a bore and stroke of 72.0 x 79.3 mm, the engine delivers a smooth and predictable power band, perfect for both city riding and open highway cruising. The air-cooled design, paired with a wet multiplate clutch and chain final drive, enhances the bike's reliability, making it a dependable partner for any journey. ### Key Features and Technology The AJS Model 31 Swift is not just about raw power; it’s also equipped with a range of features that elevate the riding experience. Its double cradle frame provides exceptional stability and handling, complemented by hydraulic telescopic front suspension and twin shock Girling rear suspension, which together create a comfortable ride over varied terrains. The expanding drum brakes, while traditional, offer adequate stopping power for safe navigation through urban landscapes. With a fuel capacity of 16 liters (4.23 gallons), riders can enjoy extended trips without the frequent need for refueling, making it an ideal choice for those who love the open road. The classic kick starter adds a touch of nostalgia, requiring a bit of rider engagement that many enthusiasts cherish. ###

Pros

    Cons

    • Classic Design: Timeless aesthetics that appeal to vintage motorcycle enthusiasts.
    • Versatile Performance: Suitable for both city commuting and long-distance rides, making it a great all-around motorcycle.
    • Reliable Engineering: A robust engine and sturdy frame that emphasize durability and ease of maintenance.
    • Limited Braking Performance: Drum brakes may not provide the same stopping power as modern disc brakes, which could be a concern for some riders.
    • Weight: At 176 kg (388 pounds), it may feel heavy for novice riders or those used to lighter models.
    • Kick Start Only: The absence of an electric starter may deter some riders who prefer modern conveniences.

    Technical details

    Source specification data

    Make
    AJS
    Model
    Model 31 650 Swift
    Category
    Allround
    Starter
    Kick
    Power
    31.40 HP (22.9 kW)) @ 6000 RPM
    Clutch
    Wet multiplate
    Ignition
    Bobine
    Fuel System
    Carburettor
    Bore X Stroke
    72.0 x 79.3 mm (2.8 x 3.1 inches)
    Compression
    7.5:1
    Displacement
    646.00 ccm (39.42 cubic inches)
    Cooling System
    Air
    Engine Details
    V2, four-stroke
    Transmission Type Final Drive
    Chain
    Dry Weight
    176.0 kg (388.0 pounds)
    Fuel Capacity
    16.00 litres (4.23 gallons)
    Power Weight Ratio
    0.1784 HP/kg
    Wheels
    Spoked
    Frame Type
    Doble cradle
    Rear Brakes
    Expanding brake (drum brake)
    Front Brakes
    Expanding brake (drum brake)
    Rear Suspension
    Twin shock Girling
    Front Suspension
    Hydraulic telescopic