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BMW R12 Single Carb
1939Allround

BMW R12 Single Carb

Key specifications

Engine
745 cc
Power
18 HP
Fuel type
petrol
Fuel capacity
3.7 L
Front brakes
Expanding brake (drum brake)
Rear brakes
Expanding brake (drum brake)

Overview

### 1939 BMW R12 Single Carb: A Classic Icon of Engineering Excellence Step back in time to 1939, a year when the world was on the brink of transformation, and so was the motorcycle industry. Enter the BMW R12 Single Carb, a masterpiece that epitomizes the all-rounder category of motorcycles. Crafted with precision and imbued with the spirit of innovation, the R12 quickly became a symbol of quality and performance. Designed for riders who seek versatility, this motorcycle strikes an exquisite balance between everyday usability and spirited riding, making it a timeless treasure for enthusiasts and collectors alike. At the heart of the R12 lies a robust 745cc two-cylinder boxer engine, delivering 18 horsepower at 3400 RPM. This four-stroke powerhouse, with its distinctive configuration, not only offers a unique aesthetic but also provides a smooth and steady power delivery that enhances the riding experience. Capable of reaching a top speed of 110 km/h (68.4 mph), the R12 is perfect for both leisurely rides and more spirited jaunts. The engine's 5.2:1 compression ratio and efficient CK 25mm carburettor provide excellent fuel economy, enabling riders to enjoy up to 69.18 miles per gallon—an impressive feat for any motorcycle of its era. The R12’s chassis is a marvel in its own right, showcasing a sturdy steel-pressed-loop frame that ensures stability and durability on various terrains. The telescopic front fork suspension offers a comfortable ride, absorbing shocks from the road, while the rigid rear suspension maintains a solid connection with the pavement. Both front and rear drum brakes with a diameter of 200mm allow for reliable stopping power, a crucial feature for safety in any riding condition. The motorcycle's classic lines, complemented by a 14-litre fuel tank and elegant design, make it a visual delight that resonates with the nostalgia of the bygone era. ####

Pros

    Cons

    • Timeless Design: Its classic aesthetic and vintage charm make it a standout piece for collectors and enthusiasts.
    • Reliable Performance: The boxer engine offers an engaging ride with smooth power delivery and impressive fuel efficiency.
    • Versatile Handling: The combination of front telescopic forks and rear rigid suspension provides a balance of comfort and road feedback.
    • Limited Speed: While adequate for leisure riding, the top speed may not satisfy those seeking high-performance capabilities.
    • Kick Start Only: The absence of an electric starter may be a drawback for some riders, especially in urban settings.
    • Maintenance Requirements: As with many vintage bikes, upkeep can be demanding, requiring specialized knowledge and parts that may not be readily available.

    Technical details

    Source specification data

    Make
    BMW
    Model
    R12 Single Carb
    Category
    Allround
    Starter
    Kick
    Power
    18.00 HP (13.1 kW)) @ 3400 RPM
    Ignition
    Magneto
    Top Speed
    110.0 km/h (68.4 mph)
    Fuel System
    Carburettor. CK 25mm
    Bore X Stroke
    78.0 x 78.0 mm (3.1 x 3.1 inches)
    Compression
    5.2:1
    Displacement
    745.00 ccm (45.46 cubic inches)
    Engine Details
    Two cylinder boxer, four-stroke
    Fuel Consumption
    3.40 litres/100 km (29.4 km/l or 69.18 mpg)
    Greenhouse Gases
    O2
    g/km. (
    O2
    -
    Carbon
    dioxide emission)
    Lubrication System
    Forced feed
    Fuel Capacity
    14.00 litres (3.70 gallons)
    Overall Width
    900 mm (35.4 inches)
    Overall Height
    940 mm (37.0 inches)
    Overall Length
    2,100 mm (82.7 inches)
    Seat
    Single seat
    Rear Tyre
    3.5-19
    Frame Type
    Steel-pressed-loop
    Front Tyre
    3.5-19
    Rear Brakes
    Expanding brake (drum brake)
    Front Brakes
    Expanding brake (drum brake)
    Rear Suspension
    Rigid-
    Front Suspension
    Telescopic fork
    Rear Brakes Diameter
    200 mm (7.9 inches)
    Front Brakes Diameter
    200 mm (7.9 inches)