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BMW R12 Twin carb
1941Sportbike

BMW R12 Twin carb

Key specifications

Engine
745 cc
Power
20 HP
Fuel type
petrol
Fuel capacity
3.7 L
Transmission
4-speed
Front brakes
Expanding brake (drum brake). Single
Rear brakes
Expanding brake (drum brake)

Overview

### Introducing the 1941 BMW R12 Twin Carb: A Classic Sport Motorcycle The 1941 BMW R12 Twin Carb is not just a motorcycle; it's a piece of history that embodies the spirit of the pre-war era. Positioned as a sport motorcycle, the R12 was BMW’s answer to the growing demand for performance and agility on two wheels. With its iconic boxer engine and timeless design, it has captivated motorcycle enthusiasts and collectors alike, establishing itself as a benchmark of innovation and style in the early 20th century. Whether you’re a vintage bike aficionado or a newcomer to the world of classic motorcycles, the R12 offers a captivating glimpse into the past, blending power, elegance, and engineering prowess. ### Engine Performance and Riding Characteristics At the heart of the R12 lies a robust 745cc two-cylinder boxer engine that delivers a respectable 19.99 horsepower at 4,000 RPM. This four-stroke marvel allows for a thrilling top speed of 120 km/h (74.6 mph), making it a formidable contender on the roads of its time. The 5.2:1 compression ratio and balanced bore and stroke measurements (78 x 78 mm) ensure smooth power delivery, while the carburettor fuel system, featuring Amal components, provides exemplary fuel efficiency and throttle response. Riders will appreciate the engaging experience provided by the 4-speed gearbox, which combines seamless shifting with a dry multiplate clutch for enhanced control. The combination of air cooling and a lightweight steel double cradle frame contributes to an exhilarating ride that balances speed and stability with remarkable finesse. ### Key Features and Technology The R12 is equipped with a host of features that reflect the cutting-edge technology of its era. With a well-engineered cartridge front suspension and rigid rear suspension, this motorcycle is designed to handle the curves and contours of the road with ease. The braking system, featuring expanding drum brakes both front and rear, provides reliable stopping power, while the single 200 mm front brake offers ample control for spirited riding. Weighing in at 185 kg (407.9 pounds) and with a sleek profile measuring 2,100 mm in length, the R12 is as agile as it is striking. The 14-litre fuel tank ensures that riders can enjoy extended journeys, while the classic kick starter adds a touch of nostalgia to the riding experience. ###

Pros

    Cons

    • Timeless Design: The R12 features a classic aesthetic that remains appealing to motorcycle enthusiasts and collectors.
    • Iconic Boxer Engine: The unique two-cylinder boxer engine provides an incredible riding experience with a low center of gravity and balanced performance.
    • Rugged Build Quality: The steel double cradle frame and robust components ensure durability and longevity, making it a reliable choice for vintage bike lovers.
    • Limited Power Output: With only 19.99 HP, it may not satisfy the needs of riders seeking high-speed performance compared to modern motorcycles.
    • Basic Braking System: The drum brakes, while adequate for the era, may feel less responsive compared to contemporary disc brake systems.
    • Rigid Rear Suspension: The rigid rear design can lead to a less comfortable ride on rougher terrain, limiting its versatility for long-distance touring.

    Technical details

    Source specification data

    Make
    BMW
    Model
    R12 Twin carb
    Category
    Sport
    Starter
    Kick
    Carrying Capacity
    300
    Power
    19.99 HP (14.6 kW)) @ 4000 RPM
    Clutch
    Dry multiplate-cable operated
    Gearbox
    4-speed
    Top Speed
    120.0 km/h (74.6 mph)
    Fuel System
    Carburettor. Amal
    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)
    Cooling System
    Air
    Engine Details
    Two cylinder boxer, four-stroke
    Lubrication System
    Wet sump
    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)
    Weight Incl Oil Gas Etc
    185.0 kg (407.9 pounds)
    Seat
    Spring-mounted seat
    Wheels
    Spoked
    Rear Tyre
    3.5-19
    Frame Type
    Steel-doble cradle
    Front Tyre
    3.50-19
    Rear Brakes
    Expanding brake (drum brake)
    Front Brakes
    Expanding brake (drum brake). Single
    Rear Suspension
    Rigid-
    Front Suspension
    Cartrige
    Front Brakes Diameter
    200 mm (7.9 inches)