Three's Company

The history of the British motorcycle industry is mostly about single- and twin-cylinder motorcycles. If this comes as a surprise to you, you haven’t been paying attention! But in its last decade as a bike building powerhouse, the BSA-Triumph group came up with a great idea: three cylinders.
Why it took so long for any motorcycle manufacturer to build a production triple is something of a mystery. Triples, it’s been often said, have the advantages of a four with the benefits of a Twin. But the converse is also true: they’re inevitably more complicated than a parallel Twin, and therefore more expensive to build. So more cylinders really only make sense for larger, heavier bikes.
For most of its existence, the British motorcycle industry focused on small-to-medium capacity, relatively lightweight bikes. But with its increased reliance in the 1960s on the American market came demands for more and more power. More power usually means more capacity, but without major development, the venerable parallel Twin had effectively reached its limit.
BSA-Triumph was on a roll in the mid sixties: US sales were strong, serious competition in large capacity bikes was minimal, and the shareholders were happy. And if management didn’t see any competition on the horizon, the development department certainly did. As early as 1962, Bert Hopwood and Doug Hele were working on a three-cylinder 750cc engine based on the 500cc Twin. The prototype used engine dimensions of 63mm by 80mm taken from the pre-unit 500cc engine, the idea being to keep the engine as narrow as possible. By 1964, the engine was showing much promise and, installed in a modified Bonneville chassis, was demonstrated to management in 1965.
Why then did it take another three years for the Trident, as the new bike would be known, to go into production? First, the prototype engine wasn’t perfect, and a P2 engine with improved cooling and more “square” dimensions of 67 by 70 was built. Next, a slanted cylinder engine was needed for a badge-engineered BSA version. And instead of adopting the lithe Bonneville look, management submitted the machine to Ogle Design to complete its cosmetics. Ogle, responsible for the acclaimed sixties supercar Reliant Scimitar came up with a bike that looked like it “couldn’t decide whether it was a dray-horse or a spaceship,” according to motorcycle journalist Steve Wilson.
Rumours of Honda’s entry into the big bike market were already rife when the Trident and Rocket 3 hit the streets in late 1968. Within six months, the Japanese machine materialized in the form of the 750-Four. Which was the better machine overall is open to discussion: the Triples produced more power and were faster, but the Honda trumped the British technology with an overhead camshaft, disc front brake, electric start and a five-speed gearbox. Though Doug Hele also built a prototype overhead cam triple, it never went into production. A disc brake and five speeds arrived in 1972,  but the electric leg took until the Norton-Villiers-Triumph T160 of 1975. BSA-Triumph went bust in ‘73.
BSA-Triumph management was determined to prove their product’s superiority on the racetrack. Gary Nixon had taken the Daytona 200 in 1967 on a Bonneville, but the Triple was the company’s main thrust for 1970. It was Dick Mann who won—on a Honda CR750. For 1971, BSA-Triumph entered 10 triples with top riders including Nixon, Mann (whom Honda had fired), Don Emde, Gene Romero, Don Castro, Dave Aldana, Jim Rice and, stepping out of retirement, Mike Hailwood. The bikes used special frames by Rob North, and engines tuned by Hele. Some used higher compression pistons leading to numerous failures in the race, but Mann’s machine held together—and was first across the line.
So BSA-Triumph proved their point: but Joe Biker wanted Honda’s smooth 750-Four, its superior technology and better reliability. Within a year, the last BSA Rocket 3 had been built and the Trident was an also-ran. The market had moved on.


OLD MOTORCYCLES DON’T DIE, THEY GO VINTAGE RACING. BRIT triples are popular mounts in the AHRMA series BEARS (British, European, American) and Formula Vintage classes. (In fact, 2006 Formula Vintage champion is surprisingly the same Gary Nixon—still racing a Trident.) It’s a real treat to see these vintage racers take to the circuit and hear the signature howl of the high-revving three-cylinder engines. That they’re still strong enough to withstand a race-meet thrashing is a testament to Edward Turner’s original two-cylinder design, Bert Hopwood and Doug Hele’s innovative and practical enlargement to three cylinders, and the skill and determination of the racers and wrenchers who keep them on the track.
One of these is Vancouver’s Tom Mellor. A fixture in the Pacific Northwest’s Sounds of the Past series, Mellor and his Trident are generally at the front when the checkered flag is waved. And while not a regular on the AHRMA national circuit, he did make the trek to Utah’s Miller Motorsports Park in September for one race round, during which the triple ran flawlessly.
As part of the festivities, Miller arranged with the Southern California Timing Association for the racers to run their bikes at nearby Bonneville. Mellor took his race bike to the salt and recorded best time of the day. Bear in mind that for the 25-or-so seconds it took to cover the measured mile, his triple was spinning at more than 9,000 rpm—not bad for a 38-year-old engine based on a 70-year-old design. Mellor’s average speed:  an astonishing 144.86059 mph.   
 

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