Back to Bike FinderYears: 1972 · 1971 · 1970
BSA A 65 Thunderbolt
1971Classic

BSA A 65 Thunderbolt

Key specifications

Engine
654 cc
Power
46 HP
Fuel type
petrol
Fuel capacity
4.8 L
Transmission
4-speed
Front brakes
Expanding brake
Rear brakes
Expanding brake

Overview

Introducing the 1971 BSA A 65 Thunderbolt, a classic British motorcycle that embodies the spirit of the golden era of motorcycling. As part of BSA's esteemed lineup, the Thunderbolt was designed for riders who craved both performance and style. With its distinctive lines and vintage charm, this bike not only appeals to collectors but also to those who appreciate the craftsmanship of yesteryear. Positioned as a versatile roadster, the Thunderbolt is as at home on winding country roads as it is cruising through city streets, making it a beloved choice among classic motorcycle enthusiasts. At the heart of the Thunderbolt lies a robust 654 cc twin-cylinder, four-stroke engine, generating an impressive 46 horsepower at 7,000 RPM. This powerhouse, coupled with a 4-speed gearbox, allows the bike to reach exhilarating speeds of up to 104.4 mph, delivering a thrilling ride that keeps the adrenaline pumping. The air-cooled engine features a compression ratio of 9.0:1, providing a perfect balance of power and efficiency. Riders will appreciate the bike’s responsive handling and smooth acceleration, thanks to its well-engineered chassis and a final drive system that ensures a seamless transfer of power to the rear wheel. The 1971 BSA A 65 Thunderbolt is rich in features that set it apart from its contemporaries. With its expanding drum brakes at both the front and rear, stopping power is reliable, allowing for confident handling even in challenging conditions. The bike's design includes a comfortable seating position and a generous fuel capacity of 18 liters (4.76 gallons), making it a practical choice for longer rides. The classic appeal is further accentuated by its elegant lines and chrome detailing, which not only enhance its aesthetics but also reflect the quality craftsmanship that BSA is renowned for. **

Pros

  • Timeless Design: The classic styling and chrome accents make the Thunderbolt a standout on the road, appealing to vintage motorcycle enthusiasts.
  • Strong Performance: With 46 horsepower, the bike delivers impressive acceleration and a top speed that satisfies the thrill-seeker in every rider.
  • Comfortable Ride: The ergonomic design and ample fuel capacity allow for longer journeys without sacrificing comfort.

Cons

  • Weight: At 220 kg (485 pounds), the Thunderbolt may feel heavy for some riders, especially when maneuvering at low speeds or during stops.
  • Braking System: While the expanding drum brakes are adequate, they may not provide the same level of stopping power or feel as modern disc brakes.
  • Limited Technology: As a classic bike, it lacks some of the modern conveniences and technologies found in contemporary motorcycles, which could deter tech-savvy riders.

Technical details

Source specification data

Make
BSA
Model
A 65 Thunderbolt
Category
Classic
Power
46.00 HP (33.6 kW)) @ 7000 RPM
Gearbox
4-speed
Top Speed
168.0 km/h (104.4 mph)
Bore X Stroke
75.0 x 74.0 mm (3.0 x 2.9 inches)
Compression
9.0:1
Displacement
654.00 ccm (39.91 cubic inches)
Cooling System
Air
Engine Details
Twin, four-stroke
Valves Per Cylinder
2
Transmission Type Final Drive
Chain
Fuel Capacity
18.00 litres (4.76 gallons)
Weight Incl Oil Gas Etc
220.0 kg (485.0 pounds)
Rear Tyre
4.00-19
Front Tyre
3.25-19
Rear Brakes
Expanding brake
Front Brakes
Expanding brake