Back to Bike FinderYears: 1953 · 1952 · 1951
BMW R25 2
1951Allround

BMW R25 2

Key specifications

Engine
247 cc
Power
12 HP
Fuel type
petrol
Fuel capacity
3.2 L
Transmission
4-speed
Seat height
29 mm
Front brakes
Expanding brake (drum brake)
Rear brakes
Expanding brake (drum brake)

Overview

The 1951 BMW R25/2 is a classic motorcycle that embodies the essence of post-war German engineering, carving a niche for itself in the allround category. Launched in a time when motorcycles were gaining momentum as a means of affordable transportation, the R25/2 quickly became a favorite among riders who appreciated its blend of reliability, style, and practicality. Sporting the iconic BMW badge, this model not only stands as a testament to the brand's commitment to quality but also as a beloved piece of motorcycle history that continues to attract enthusiasts and collectors alike. At the heart of the R25/2 lies a robust 247 cc single-cylinder, four-stroke engine that produces a respectable 11.96 horsepower at 5600 RPM. This power allows it to reach a top speed of 80 km/h (49.7 mph), making it a competent performer for both city commuting and leisurely country rides. The 6.5:1 compression ratio and Bing carburettor fuel system ensure smooth operation and efficient fuel consumption, with an impressive rating of 2.90 liters per 100 km (approximately 81.11 mpg). Riders will appreciate the simplicity of the 4-speed gearbox, complemented by a reliable shaft drive that minimizes maintenance while providing smooth and confident power delivery. The R25/2’s design is equally notable, featuring a steel single cradle frame that provides a solid foundation for its suspension system. The front and rear drum brakes, both measuring 160 mm, offer reliable stopping power, while the cartridge front suspension and twin shock-plunger rear suspension ensure a comfortable ride over varying terrains. With a seat height of 730 mm, it offers a low center of gravity, making it accessible for riders of different statures. Additionally, the classic kickstarter adds a nostalgic touch, appealing to those who appreciate the raw, mechanical feel of vintage motorcycles. **

Pros

  • Fuel Efficiency: With a fuel consumption of just 2.90 liters per 100 km, the R25/2 is a cost-effective option for daily rides.
  • Simplicity and Reliability: The straightforward design and shaft drive system contribute to low maintenance and high reliability, ideal for both seasoned and novice riders.
  • Classic Appeal: Its timeless design and iconic BMW styling make it a standout choice for classic motorcycle collectors and enthusiasts.

Cons

  • Limited Power: The relatively low horsepower may not satisfy riders seeking high-performance thrills or faster speeds.
  • Drum Brakes: While effective, drum brakes may not offer the same stopping power and feel as modern disc brakes, potentially limiting performance in more demanding riding conditions.
  • Kickstarter Only: The absence of an electric start can be a drawback for those who prefer the convenience of modern starting systems, especially in cold weather.

Technical details

Source specification data

Make
BMW
Model
R25 2
Category
Allround
Starter
Kick
Power
11.96 HP (8.7 kW)) @ 5600 RPM
Clutch
Single plate dry-cable operated
Gearbox
4-speed
Ignition
Battery
Top Speed
80.0 km/h (49.7 mph)
Fuel System
Carburettor. Bing
Bore X Stroke
68.0 x 68.0 mm (2.7 x 2.7 inches)
Compression
6.5:1
Displacement
247.00 ccm (15.07 cubic inches)
Cooling System
Air
Engine Details
Single cylinder, four-stroke
Fuel Consumption
2.90 litres/100 km (34.5 km/l or 81.11 mpg)
Greenhouse Gases
O2
g/km. (
O2
-
Carbon
dioxide emission)
Lubrication System
Wet sump
Transmission Type Final Drive
Shaft drive (cardan)
Seat Height
730 mm (28.7 inches) If adjustable, lowest setting.
Fuel Capacity
12.00 litres (3.17 gallons)
Overall Width
790 mm (31.1 inches)
Overall Height
730 mm (28.7 inches)
Overall Length
2,020 mm (79.5 inches)
Ground Clearance
108 mm (4.3 inches)
Weight Incl Oil Gas Etc
140.0 kg (308.6 pounds)
Seat
Solo seat with springs
Rear Tyre
2.99-19
Frame Type
Steel-single cradlel
Front Tyre
2.99-19
Rear Brakes
Expanding brake (drum brake)
Front Brakes
Expanding brake (drum brake)
Rear Suspension
Twin shock-Plunger
Front Suspension
Cartridge
Rear Brakes Diameter
160 mm (6.3 inches)
Front Brakes Diameter
160 mm (6.3 inches)