CarBrandLogos archive · BSA · 1968

BSARocket 3

Britain's answer to Honda, launched weeks before the CB750 made it look old.

Photo: SG2012 · CC BY 2.0

The story

A defining chapter in BSA history.

Explore the ideas, engineering and context that shaped the BSA Rocket 3, then continue into its specifications and place in the marque's lineage.

Origins

The BSA and Triumph group needed something bigger than a 650 twin, and the cheapest route there was to add a cylinder. Bert Hopwood and Doug Hele developed a 740 cc air-cooled overhead-valve triple, effectively a twin and a half, and it was sold in two forms: as the Triumph Trident with vertical cylinders, and as the BSA Rocket 3 with the block canted forward and a different frame. Both went on sale in 1968.

Triumph X75 Hurricane · MikeSchinkel on Flickr.com, MikeSchinkel.com · CC BY 2.0

Design and engineering

The engine was genuinely good — smoother than a twin, hard-revving, and strong enough to make the bike one of the fastest things on the road. The packaging was not. Development had dragged on for years while management dithered, and the styling of the first Rocket 3, with its slab-sided tank and ray-gun silencers, was done by an external consultancy and widely disliked. Then, weeks after launch, Honda showed the CB750: four cylinders, electric start, a disc brake, and a price the British bikes could not match.

BSA Rocket 3 motorcycle · TR001 · CC BY-SA 3.0

In production

What saved the triple's reputation was racing. Rob North built lightweight frames for factory machines that won the Daytona 200 in 1971 with Dick Mann and dominated Formula 750 in Britain, and the works racer known as Slippery Sam took five consecutive Isle of Man Production TT wins. Dry clutch, four speeds and chain drive were standard, with five-speed gearboxes arriving on later T150V and T160 versions.

1965 P1 Triumph Triple Prototype · London Motorcycle Museum · CC BY 3.0

Legacy

Production continued to 1975, by which time BSA had collapsed and the triple survived only in Triumph form. It is the last genuinely competitive engine the British industry produced, and it arrived about three years too late.

At a glance