3TA

1958 Triumph 3TA Technical Analysis & Specification Breakdown

Built around Triumph's sport motorcycle platform, the 1958 Triumph 3TA relies on a 349 cc (21.3 cu in) twin, four-stroke powerplant. In factory specification, peak output is rated at 21 HP (15.3 kW), transferring power to the rear wheel through chain final drive. With a specific output of 60.2 HP per liter, the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.

On the scales, the 3TA measures 156.5 kg (345 lbs) dry, translating to a power-to-weight ratio of 0.13 HP/kg (7.45 kg per horsepower).

Within MotoLibrary's Triumph archive, this model family spans 10 indexed model years from 1957 to 1966, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.