Classic and Classy Motorcycles Ltd

Historical Context

By the late 1970s, Triumph was facing increasing competition from Japanese manufacturers, who were producing more advanced and reliable motorcycles. The Triumph Bonneville T140E, introduced in 1978, was Triumph’s answer to this challenge. With a larger 750cc engine, electronic ignition, and improved emissions standards (hence the "E" in T140E), this model represented an attempt to modernize the iconic Bonneville while retaining its classic British appeal. The T140E was part of the long-running Bonneville series, which had already cemented its place as one of the most famous motorcycles of all time, known for its blend of performance, agility, and style.

Technical Specifications and Features

• Year: 1978
• Make: Triumph
• Model: Bonneville T140E
• Engine Displacement: 750cc
• Engine Type: Air-cooled, parallel twin, four-stroke
• Transmission: 5-speed manual
• Brakes: Disc front and rear
• Fuel System: Twin Amal Mk II carburetors
• Fuel Capacity: 4.2 gallons
• Wheelbase: 57.5 inches
• Seat Height: 31 inches
• Dry Weight: Approximately 400 pounds
• Key Features: The T140E featured an enlarged 750cc engine for more power and torque, along with improved emissions controls and electronic ignition. Its twin Amal carburetors offered excellent throttle response, while the twin disc brakes provided improved stopping power over earlier models.

Project Potential

The 1978 Triumph Bonneville T140E offers excellent potential as a restoration project. With its relatively simple mechanics and the wide availability of parts, the T140E can be restored to its original factory condition or customized into a unique build. The model’s larger engine and modern features make it appealing for riders who want the classic Triumph experience but with a bit more power and reliability than earlier Bonnevilles. Whether you’re looking to restore it for display or regular use, the T140E’s iconic design and strong performance make it a rewarding project.

Riding Experience

Once restored, the 1978 Triumph T140E delivers a smooth and enjoyable riding experience. The 750cc parallel twin engine provides plenty of power for highway cruising and city riding alike, with a broad powerband and ample torque. The bike’s five-speed transmission allows for more flexibility at higher speeds, while the improved disc brakes provide better stopping power than the drum brakes of earlier models. Despite its increased size and weight compared to earlier Bonnevilles, the T140E maintains the nimble handling and balance that the Bonneville series is famous for.

Design and Aesthetic Appeal

The design of the 1978 T140E is a perfect blend of classic British style with modern updates. The bike retains the sleek, clean lines of earlier Bonnevilles, with its iconic teardrop-shaped fuel tank and chrome accents. The larger engine and twin exhaust pipes give the bike a more muscular look, while its minimalist bodywork and polished metal components provide a timeless, elegant appearance. The T140E strikes a balance between traditional aesthetics and the demands of modern motorcycling, making it a beautiful addition to any collection.

Legacy and Collectibility

The 1978 Triumph Bonneville T140E is highly collectible due to its blend of classic design and modern engineering. As one of the last models produced before Triumph’s financial struggles in the late 1970s and early 1980s, the T140E holds a special place in Triumph’s history. Restoring a T140E not only preserves an important piece of British motorcycling heritage but also adds significant value to any vintage motorcycle collection. The T140E continues to appreciate in value, making it a worthwhile investment for enthusiasts and collectors alike.