Ariel 4G Square Four Mark I 1949 - Specifications & Review

1949 Ariel 4G Square Four Mark I: A Timeless Classic

Introducing the 1949 Ariel 4G Square Four Mark I, a motorcycle that stands as a testament to the innovative spirit of post-war Britain. Designed by the legendary Edward Turner, this allround motorcycle embodies a unique blend of engineering prowess and aesthetic appeal, making it a coveted piece among classic motorcycle enthusiasts. With its distinctive square four-cylinder engine, the 4G Square Four, affectionately nicknamed the “Squariel,” was positioned as a sophisticated option for riders seeking both performance and comfort. The model emerged during a time when motorcycling was gaining popularity, appealing to those who craved adventure and freedom on two wheels.

At the heart of the 4G Square Four is its captivating 995cc square four-cylinder engine, delivering a robust 35 HP at 5,500 RPM. This power allows the motorcycle to effortlessly reach a top speed of 144.8 km/h (90 mph), providing riders with a thrilling experience on the open road. The engine's compression ratio of 6.0:1, combined with its two-valve per cylinder design, ensures that the bike strikes a balance between smooth acceleration and responsive handling. The air-cooled engine, paired with a 4-speed gearbox and chain final drive, offers a classic riding experience that resonates with purists, while the oil-damped telescopic front suspension and plunger-link rear suspension enhance comfort and control, making it suitable for both leisurely rides and spirited jaunts.

The Ariel 4G Square Four Mark I is not just about power; it’s also a marvel of mid-century engineering. With a lightweight frame constructed from a tubular single loop design, the bike weighs in at a manageable 197 kg (434 lbs), allowing for nimble handling. The motorcycle features traditional drum brakes, with a front diameter of 203 mm and a rear diameter of 178 mm, providing reliable stopping power. The captivating red and silver color options add a touch of elegance, while the kick starter evokes the nostalgia of classic motorcycling. The transition from cast-iron to aluminum alloy for the cylinder head and barrel not only contributed to weight reduction by 14 kg but also marked a significant advancement in motorcycle technology for its time.

Pros:

1. Unique Engine Configuration: The square four-cylinder engine offers a distinct and smooth power delivery that sets it apart from traditional inline or V-twin engines.
2. Classic Aesthetics: With its vintage styling and striking color options, the 4G Square Four is a head-turner, making it a favorite among collectors and enthusiasts.
3. Comfortable Ride: The combination of effective suspension and lightweight frame provides a comfortable riding experience, suitable for long trips or daily commuting.

Cons:

1. Limited Power: While 35 HP is adequate for leisurely rides, it may fall short for those seeking high-performance thrills compared to modern motorcycles.
2. Drum Brakes: The traditional drum brake system, while reliable for its time, may not provide the same level of stopping power as contemporary disc brakes.
3. Kick Start Only: The absence of an electric starter may deter some riders who prefer the convenience of modern starting systems, especially in adverse conditions.

In summary, the 1949 Ariel 4G Square Four Mark I is a remarkable motorcycle that captures the essence of mid-20th century motorcycling. Its innovative design, combined with a charismatic engine and classic features, ensures that it remains a cherished piece of motorcycle history for generations to come.