The Triumph Bonneville is a standard motorcycle featuring a parallel-twin four-stroke engine and manufactured in three generations over three separate production runs.

The steering angle was altered and improved forks were fitted a couple of years later, which, together with the increased stiffness enabled overall performance to match that of the Bonneville's rivals.

After a factory lock-in by the Meriden workers for over a year kept Triumph twin cylinder models off the market place, only the larger Bonneville returned afterwards in 1975.

By then, the gearchange foot lever had been moved from right to left to comply with new regulations mandated for the American market and a rear disc brake fitted.

Several T140 models followed featuring various styling and engineering modifications and refinements including electronic ignition from 1979 and electric starting from 1980 until production ceased with the closure of the Meriden works in 1983.

Triumph Motorcycles was acquired by businessman John Bloor, who licensed a company called Racing Spares in Devon, run by Les Harris to manufacture the T140 Bonneville.

Originally built exclusively in Hinckley, England, some models are now (2014) produced at the company's Thailand manufacturing facility, which also makes components and accessories for various Triumph motorbikes.