1971 BSA 750cc Rocket 3 - Rocket Science

Text: Robert Smith • Photography: Robert Smith

When BSA re-launched the 750cc Rocket 3 in 1971, they created an outrageously impractical motorcycle. The factory painted the frame "dove grey," a kind of pale taupe that showed dirt like your mom's white gloves. The tiny gas tank held 2.5 U.S. gallons, giving the thirsty triple a range of around 70 miles. The front brake (the BSA/Triumph group twin leading shoe) was useless: it wouldn't have stopped a Schwinn, let alone a 500-lb. motorcycle capable of 125mph. All of that aside, I just knew that one day I'd have one...

Triples traced
The BSA/Triumph triple story begins in the early 1960s. The autocratic, obstinate and domineering Edward Turner then ran Triumph. And while Triumph was part of the BSA Group, Turner ran his division as his personal fiefdom, resisting all efforts to introduce commonality in the BSA and Triumph ranges.

Turner's greatest contribution to the industry had been the Speed Twin of 1938, the machine that established the design parameters for the parallel twin engine, adopted by almost every British manufacturer in the 1940s and '50s. But his mind was closed to new ideas - unless they were his own - and Triumph failed to innovate to meet new competitors.

Though there was no love lost between them, Bert Hopwood had worked with Edward Turner as designer, draftsman and engineer for much of his career. It was Hopwood who often re-engineered Turner's designs to make them practical and reliable. By the early sixties, Hopwood realized a new engine would soon be needed to replace the aging parallel twins.

Hopwood and his assistant Doug Hele drafted a three-cylinder engine: effectively a unit-construction Triumph 500 twin with an extra cylinder, giving it 750cc. But Turner was opposed to the triple (as he was to most of Hopwood's ideas), and the project went no further until Turner retired in 1964.

Hopwood and Hele fitted their engine into the Bonneville frame and cycle parts. The prototype worked well and looked great (it's now in the London Motorcycle Museum in Greenford, West London), but senior management was unimpressed - until word leaked in 1967 that Honda was working on a 750 multi. The project was revived, with the engine redesigned and fitted in a new frame using cycle parts from the existing 650 twins.

Two bikes were built, the Triumph Trident and BSA Rocket 3, and though mechanically identical, they differed in three distinct ways. The Triumph version's timing cover was shaped to echo the triangular cover on the twins, while the BSA's cases followed their "power egg" concept. The Trident had vertical cylinders while the BSA's were canted forward 15 degrees. And the frames were different: the Rocket 3 used a modern twin-tube all welded frame, while the Trident continued Triumph tradition with a single tube lug-and-braze frame.

Rather than adopt traditional styling for the new triples, BSA/Triumph hired consultants Ogle Design to dress the new triples. Ogle drafted a bike with a slab-sided gas tank and side panels, and the famous "ray gun" three-outlet mufflers. Depending on your point of view, it was either a disaster or a classic. Motorcycle journalist Steve Wilson wrote that the Rocket 3 "couldn't decide if it was a dray-horse or a spaceship." When it was launched in 1968, the American market hated it.

But performance it had a-plenty. The Triumph Trident/BSA Rocket 3 was then the fastest production motorcycle, comfortably outpacing and out-handling the new Honda 750 launched a few months later. But the Honda had five gears, overhead camshaft, disc brake, and - electric start (something the Rocket 3 never acquired, and the Trident only in 1975, its last year of production).

Disappointing sales led to a (mainly) cosmetic makeover for 1971. In line with the new BSA and Triumph twins, the triples received the new group cycle parts: skinny alloy forks, the conical hub brakes, chrome wire headlamp and fender stays, and more restrictive mufflers. The Trident's styling was more conservative than the Rocket 3's, looking more like the 1971 Bonneville.

And 1971 should have been a banner year for Rocket 3 sales. In 1970, the BSA/Triumph team's best performance was second at Daytona behind Dick Mann's Honda. For 1971, the triples had new "lowboy" frames, tuned engines and a team of six riders - including Mann, who had been let go by the Honda team. In what turned out to be a battle of attrition, the BSA Rocket 3s came home 1-2-3 in the 200-mile race, with Mann first over the line.

The victorious Brits were never able to capitalize on their victory, however. By 1972, BSA had effectively gone bust and the Triumph Meriden factory was scheduled for closure. In all, only around 7,000 Rocket 3s were built, including 1,000 1971 models and 200 1972s.

But the triples' race winning ways weren't over: they dominated Formula 750 and Production racing in Britain over the next few years. Most notable was the Trident known as Slippery Sam (after a ruptured oil line drenched its competitors at the 1970 Bol d'Or). With five different riders, Sam won the Isle of Man Production TT every year from 1971 to 1975!

Rocket Revival
The first time I saw my Rocket 3 it was strapped to a pallet in a dim warehouse after a truck trip from Texas. I'd bought it based on pictures on the Internet, and the reality was somewhat depressing. It was well used and weary looking, while the Gulf of Mexico air had taken its rusty toll on the frame and wheels. I'd hoped to just clean it up and ride it, but a full restoration would be necessary.

I handed the project to Rick Brown, a Triumph restoration specialist in Victoria, BC. Between us, we agreed on the work that had to be done; the bike was completely stripped and parts sent for plating and refurbishing while Rick did the painting. I decided to nix the dove-gray paint, opting for a more practical (and traditional) black. (Though no one was keeping records by that time, it's likely the factory built some 1971 Rockets with black frames anyway after receiving complaints about the gray frame from U.S. dealers.) The tank and side covers are BSA Firecracker Red, the correct color for 1971. The only other deviation from stock: longer front brake operating levers for the weak front brake.

When straddling the Rocket 3, it's immediately apparent this is no British twin. It's bigger, bulkier and heavier. Starting is different, too. Instead of the lunge usually required to fire a British twin, a series of prods (much like starting a two-stroke) works better. The engine even sounds a little like a two-stroke twin, with a burbling exhaust note rather than the staccato twin beat - though there's also plenty of mechanical noise from the valve train, a Triumph trait. Triple clutches come in for much criticism, but mine is light and drag free. Snicking into first, it's necessary to rev the engine to pull away. The engine has little of a Brit twin's lowdown grunt.

This is a fast motorcycle. Though 58hp doesn't sound like much in 2004, it will take the Rocket 3 comfortably over 100 mph, and while the handling is excellent (in a crude, old-fashioned way), the brakes are woeful. The rear works fine, but the front has no bite at all, even with the extended levers. (The Trident got a disc brake for 1973, but that was after Rocket 3 production had ceased.)

High-speed cruising is where the Rocket 3 comes into its own. At engine speeds that would loosen teeth on a twin, the Rocket 3 is smooth and willing, with power to spare for passing. But it needs revs: three 27mm Amal carbs and sport camshaft timing means the engine is over-choked below 5,000rpm. But wind the throttle open above that, and the intake roar competes lustily with the characteristic triple exhaust howl. It's pure music: a triple concerto.

Should you buy one?
BSA/Triumph triples aren't for the faint of heart or the light of wallet: they share electrical and carburetion gremlins with the twins from which they're derived, plus a whole raft of additional issues; like the clutch (borrowed from a Mini), rapid valve guide wear, head gasket problems, and so on. Most of these are fixable now - in true British bike fashion, the development work has been done by the thousands of owners - but at a price. Many of the remaining problems stem from the restrictions placed on design by the available machine tools at the BSA factory where all the triples were built.

But the riding experience is so different from the traditional British twin that every vintage bike fan should at least try one - once, anyway!