
AJS Model 31 650 Swift
Key specifications
Overview
The 1962 AJS Model 31 650 Swift stands as a testament to the golden age of British motorcycling, perfectly encapsulating the spirit of adventure and freedom on two wheels. Positioned as an allround motorcycle, it appeals to both the casual rider and the enthusiast seeking a classic ride that combines style with substance. With its unmistakable charm and robust build, the Model 31 Swift has remained a favorite among collectors and vintage aficionados, offering a nostalgic glimpse into a time when craftsmanship and character defined the motorcycle market. At the heart of the AJS Model 31 is a powerful V2, four-stroke engine that displaces 646cc, delivering a respectable 31.4 horsepower at 6000 RPM. This power, coupled with a compression ratio of 7.5:1, provides an engaging riding experience that is both spirited and smooth. The engine is mated to a wet multiplate clutch and a chain final drive, allowing for seamless power transfer and enhanced control. Riders will appreciate the hydraulic telescopic front suspension and the twin shock Girling rear suspension, which together deliver a balanced ride, soaking up bumps and providing stability whether navigating city streets or embarking on longer journeys. Innovation meets classic design in the AJS Model 31 Swift, with features that reflect its era while still offering practical functionality. The double cradle frame ensures rigidity and durability, while the expanding drum brakes at both the front and rear provide reliable stopping power. The kick starter adds a touch of authenticity, allowing riders to engage with their machine in a way that modern electric starters cannot replicate. With a fuel capacity of 16 liters (approximately 4.23 gallons), the Swift is well-suited for longer rides, offering a good range for exploration without frequent stops at the pump. **
Pros
- Classic Appeal: The vintage aesthetics and robust build of the Model 31 Swift make it a standout in any collection or at vintage motorcycle events.
- Engaging Ride: The powerful V2 engine and responsive handling provide a thrilling riding experience, suitable for both urban commutes and weekend getaways.
- Simplicity and Reliability: The straightforward mechanical design and kick starter contribute to the bike's reliability and ease of maintenance.
Cons
- Limited Braking Performance: The drum brakes, while adequate for the era, may feel less responsive compared to modern disc brake systems, requiring more attention from the rider.
- Weight Considerations: At 176 kg (388 lbs), the Model 31 may be considered heavy by contemporary standards, which could affect maneuverability, especially for new riders.
- Fuel Efficiency: While the 16-liter tank offers decent range, the vintage engine may not match the fuel efficiency of modern motorcycles, potentially resulting in more frequent refueling.
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
- Seat
- Dual
- Wheels
- Spoked
- Rear Tyre
- 3.25-19
- Frame Type
- Doble cradle
- Front Tyre
- 3.25-19
- Rear Brakes
- Expanding brake (drum brake)
- Front Brakes
- Expanding brake (drum brake)
- Rear Suspension
- Twin shock Girling
- Front Suspension
- Hydraulic telescopic