1971 BSA B50MX
Introduced in 1971, the 1971 BSA B50MX features a 499cc OHV single engine producing 34hp, establishing itself as a notable dual-sport.
Specifications
Engine
- Type
- OHV single
- Displacement
- 499 cc
- Cylinders
- 1
- Power
- 34 hp @ 6000 rpm
- Torque
- 38.0 Nm
- Compression
- —
- Bore × Stroke
- 84.0 × 90.0 mm
- Cooling
- Air-cooled
- Fuel System
- Amal carburetor
Chassis & Transmission
- Frame
- Steel single cradle
- Front Suspension
- Telescopic fork
- Rear Suspension
- Twin shock
- Front Brake
- Drum
- Rear Brake
- Drum
- Front Tyre
- —
- Rear Tyre
- —
- Transmission
- 4-speed
- Final Drive
- Chain
Performance
- Top Speed
- 140 km/h (87 mph)
- ¼ Mile
- —
Dimensions & Weight
- Dry Weight
- 149 kg (328 lbs)
- Wet Weight
- 161 kg (355 lbs)
- Seat Height
- 830 mm
- Wheelbase
- 1380 mm
- Ground Clearance
- —
- Fuel Capacity
- 10.0 L
History & Story
When BSA unveiled the 1971 BSA B50MX in 1971, it signaled the company's commitment to the dual-sport segment. Built in United Kingdom, this dual-sport embodied the spirit of 1970s motorcycling.
At the heart of the 1971 BSA B50MX sits a 499cc OHV single engine producing 34 horsepower at 6000 rpm. The single-cylinder powerplant features a single-cylinder layout with air-cooled cooling, fed by Amal carburetor. Power reaches the rear wheel through a 4-speed transmission and chain final drive.
Weighing 149 kg (328 lbs) dry, the 1971 BSA B50MX uses a steel single cradle frame, telescopic fork front suspension, and twin shock rear suspension. The braking system comprises drum front and drum rear units.
Performance-wise, the 1971 BSA B50MX achieves a claimed top speed of 140 km/h (87 mph). With a fuel capacity of 10.0 liters, it offers reasonable range for dual-sport duties. The seat height of 830 mm makes it comfortable for most riders.
At the heart of the 1971 BSA B50MX sits a 499cc OHV single engine producing 34 horsepower at 6000 rpm. The single-cylinder powerplant features a single-cylinder layout with air-cooled cooling, fed by Amal carburetor. Power reaches the rear wheel through a 4-speed transmission and chain final drive.
Weighing 149 kg (328 lbs) dry, the 1971 BSA B50MX uses a steel single cradle frame, telescopic fork front suspension, and twin shock rear suspension. The braking system comprises drum front and drum rear units.
Performance-wise, the 1971 BSA B50MX achieves a claimed top speed of 140 km/h (87 mph). With a fuel capacity of 10.0 liters, it offers reasonable range for dual-sport duties. The seat height of 830 mm makes it comfortable for most riders.
Known Issues
- Oil leaks typical of British singles and twins
- Lucas electrical components unreliable
- Primary chain adjustment critical
- Quality control issues from late-era production
Fun Facts
- BSA was in financial decline during this period, making late-model bikes historically significant
- The 1971 BSA B50MX was produced in BSA's United Kingdom facilities
- The 1971 BSA B50MX featured a steel single cradle frame typical of 1970s design philosophy
Collector Information
- Parts Availability
- Moderate
- Collector Rating
- 5/10
Resources & Parts
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