
BSA M 21
Key specifications
Overview
Introducing the 1954 BSA M 21: A Classic Allrounder The 1954 BSA M 21 stands as a testament to British motorcycle engineering during the post-war era, capturing the spirit of adventure and practicality that defined the era. Positioned as an allround motorcycle, the M 21 was designed to cater to a wide range of riders, from those seeking a reliable daily commuter to enthusiasts yearning for weekend escapades. With its robust construction and timeless styling, this motorcycle embodies the essence of mid-20th century craftsmanship, making it an enduring favorite among collectors and vintage motorcycle aficionados alike. Engine Performance and Riding Characteristics At the heart of the M 21 lies a muscular 591 cc single-cylinder, four-stroke engine, delivering a respectable 15 horsepower at 4,000 RPM. This power, while modest by modern standards, is perfectly suited for the bike's intended purpose, offering a smooth and torquey ride that is both enjoyable and confidence-inspiring. The bore and stroke dimensions of 82.0 x 112.0 mm create a harmonious balance that favors low-end torque, making it ideal for urban commuting and leisurely country rides. With a wet multiplate clutch and chain final drive, the M 21 provides a seamless transmission experience, ensuring that each ride is as engaging as it is accessible. The kick starter adds a touch of nostalgia, inviting riders to connect with the machine in a way that electric starters simply can’t replicate. Key Features and Technology The BSA M 21 showcases a blend of straightforward engineering and functional design. Its single cradle frame combines strength and lightness, making it agile and easy to handle, while the hydraulic telescopic front suspension and twin-shock rear suspension provide a comfortable ride over various terrains. The expanding drum brakes, both front and rear, offer reliable stopping power, ensuring that safety is paramount while navigating the roads. With a fuel capacity of 11.36 liters, riders can enjoy extended journeys without the constant worry of refueling. The M 21 is not just a motorcycle; it’s a reliable companion for those who appreciate the art of classic riding. **
Pros
Cons
- Classic Aesthetic: The M 21's vintage design and polished features evoke nostalgia, making it a standout at any motorcycle gathering.
- Simple Maintenance: With straightforward mechanical components, the M 21 is relatively easy to maintain, appealing to DIY enthusiasts and those new to motorcycle care.
- Comfortable Ride: The combination of its suspension system and ergonomic design delivers a comfortable riding experience, perfect for long journeys or daily commutes.
- Limited Power: With only 15 horsepower, the M 21 may struggle to keep up with modern traffic speeds, requiring riders to be more cautious on highways.
- Drum Brakes: While reliable, the drum brakes can lack the stopping power and responsiveness found in modern disc brake systems, potentially reducing confidence for new riders.
- Kick Start Only: The absence of an electric starter can be a challenge for some, especially in colder climates or for those less experienced with kick starting techniques.
Technical details
Source specification data
- Make
- BSA
- Model
- M 21
- Category
- Allround
- Starter
- Kick
- Power
- 15.00 HP (10.9 kW)) @ 4000 RPM
- Clutch
- Wet multiplate
- Ignition
- Magneto
- Fuel System
- Carburettor
- Bore X Stroke
- 82.0 x 112.0 mm (3.2 x 4.4 inches)
- Displacement
- 591.00 ccm (36.06 cubic inches)
- Engine Details
- Single cylinder, four-stroke
- Transmission Type Final Drive
- Chain
- Dry Weight
- 180.0 kg (396.8 pounds)
- Fuel Capacity
- 11.36 litres (3.00 gallons)
- Power Weight Ratio
- 0.0833 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
- Hydraulic telescopic