Triumph Trident
Vibration is Always a Problem
British twins like Triumph’s legendary 650cc Bonneville and TR6, were powerful machines in their day, and capable of some high revs to make that power. The problem and the limiting factor to extracting more power was engine vibration. Those two pistons rising and falling together, balanced by an enormous crankshaft and flywheel that were supported by only two main bearing was a recipe for wicked engine vibration at high RPMs. Vibration like this can destroy an engine in seconds. Many things were tried, but nothing seems to solve the problem.
The Triumph Trident was erroneously nicknamed 'a Daytona-and-a-half', referring to Triumph's 500cc twin. But, the Trident wasn't spun off of that component set, too bad too, because it was an oversquare engine. Instead, the Triumph/BSA 250 single component set were used, possibly because it was undersquare, with smaller bores, which allowed for a narrower engine.
In 1962 Bert Hopwood left AMC (Associated Motor Cycles), aka: Matchless and AJS, to take over engineering at Triumph. Matchless/AJS had done something about the vibration in their own twins that no one else in the British motorcycle industry had tried. They added a center main bearing to the crank which greatly improved the vibration problem but didn’t eliminate it altogether. Hopwood was well familiar with the vibration issue. When he landed at Triumph, he made it his personal goal to solve it once and for all.
The Triumph Trident had a very complex set of engine cases. Instead of splitting the crankcases horizontally like Japanese bikes, they insisted on splitting them vertically, like the singles and twins they'd always built. Not easy to do when you need to place 2 center main bearings.
Triumph Trident Concept
What he came up with was a totally new direction of thought. What if we packaged three component sets from the Triumph/BSA 250cc single, creating a 750cc three-cylinder (triple)? By 1965, running prototypes were being tested and demonstrated. It was a fairly natural process since the new triple would use the same frame and running gear at the Triumph Bonneville and TR6 lines. The bike performed well and the green light was given to move toward production.
This is the first Triumph Trident prototype, finished in 1966, hand-built by Bert Hopwood. Everything but the new 3-cylinder engine was straight off the 1966 Triumph Bonneville.
Triumph Trident Could Have Changed the World
To be named the Triumph T150 Trident, the plan was to release it to the market in 1966 as a 1967 model, a move that would have changed history. This would have put them a full two years ahead of the release of Honda’s game-changing CB750 Four. It would have been the first ‘multi-cylinder’ (ie: more than two) motorcycles on the US market and would certainly have been the fastest bike on the planet for several important years. Alas it didn’t happen.
BSA owned Triumph, and while the Triumph brand was outselling BSA in the crucially-important US market, BSA resented Triumph for it’s success. They were literally jealous! BSA had always been the top-selling brand in the UK and throughout Britain’s vast global empire. But in the US, the Yanks loved Triumphs! And it goaded them. So, when BSA got wind of this new 3-cylinder Triumph super bike, they would only approve it if Triumph could create a BSA version. And it couldn’t look like the Triumph triple. Instead of ‘badge engineering’ the two bikes to share major components but be styled and tuned differently (like General Motors did with Chevrolet, Pontiac, Buick and Oldsmobile around the same time), which would have been the smart move, prideful BSA demanded that the engine for the BSA version look different than the Triumph version.
LEFT: The Triumph Trident engine has vertical cylinders. RIGHT: The BSA Rocket 3 engine's cylinders slant forward at 12-degrees. This required all new engine cases, otherwise all internal components were identical. The change was purely cosmetic.
BSA Delays Triumph Trident's Launch
While the Triumph Trident’s cylinders were vertical, BSA decided they wanted theirs to be slated forward at 12 degrees. It sounds like a small change, but it required a completely new set of lower-end engine cases, the costliest and most complex component of the engine. They also wanted the outer covers to look less ‘Triumph-like’ and more ‘BSA-like’. All of these changes cost money and time that they didn’t have. BSA slow-walked the whole project until in 1968, two years after Triumph’s original proposed launch date, Honda announced the pending release of it’s new 4-cylinder superbike. Suddenly BSA and Triumph were behind the 8-ball. BSA hit the gas and rushed the project to completion to try to beat the big Honda’s release. In the end, instead of beating Honda to market by two full years, they barely made it by two months.
When the 1969 Triumph Trident launched it was pretty homely, unusual for a Triumph. Check out that 'shoebox tank' and those 'ray gun mufflers'.
Triumph Trident Off to a Rocky Start
The new Triumph T150 Trident and it’s sister-bike, the BSA A75 Rocket 3 were released to rave reviews at the time, and performed quite well in testing. They were certainly fast and handled well. But, they lacked a 5-speed gearbox, they were still running drum brakes when most of the industry was switching over to discs, and no electric start, you had to kickstart this bad boy. Two months later the Honda CB750 Four was released to an adoring market. It had it all: Big, powerful engine with all the latest technology, 5-speed, front disc brake, and that all important electric starter. And, they were totally reliable and never leaked oil, two things that couldn’t be said about the two British triples. AND, they were cheaper. Thanks to a favorable currency exchange rate between Japan and the US at the time, and the reverse between the UK and the US, the British bikes were going to cost more, no matter what. But the Japanese also had the full weight of their government behind them, supporting them in every way to strengthen their industries at home. In Britain, the Socialist Party was running things and they hated businesses, manufacturers, management, investors, etc. They offered no help to the beleaguered motorcycle industry there, or the car industry, which also collapsed during this era.
It took less than one model year for Triumph to get their act together on this, and by the end of the 1969 model year, they were using the handsome Bonneville bodywork. Early bugs were worked out and the Trident became a very fine machine, in light of its shortcomings. They were always fast and great-handling, the sounded great and looked astounding! Improvements were steadily made, year-to-year.
It didn't take Triumph long to make the Trident look like a proper Triumph. The 1971 Triumph Trident benefited by the new running gear and bodywork introduced on the 1971 'oil-in-frame' 650s. Note the conical brakes.
Triumph Trident Improves Year-to-Year
In 1969 and 1970, the Tridents used the same running gear as the Bonneville and TR6, including frame, forks, wheels and brakes, which were the excellent twin-leading-shoe (TLS) brakes up front. In 1971, they benefitted from the new running gear introduced on Triumph’s 650 line, including new forks, new wheels, now with conical drum brakes (no discs like everyone else) and the great-looking bodywork shared with the 650s. In 1973, some much-needed and long-awaited improvements arrived in the form of a 5-speed gearbox and a front disc brake.
By this time, Triumph, now owned by Norton (BSA was now gone) was in serious trouble. Norton wanted to close Triumph’s legendary Meriden factory and move production over to their own factory in Donington Park and the Triumph workers revolted. They blockaded themselves in the factory, letting nothing in or out for nearly the entire 1974 model year. By 1975, Norton relented and allowed the workers to form their own Meriden Co-Op and buy the Triumph brand. They were underfunded from the start and struggled to produce fewer and fewer bikes until they just couldn’t go any further and closed in 1983.
The 1973 Triumph Trident was the first to get a 5-speed gearbox and front disc brake, but still no electric starter.
Triumph Trident gets a Full Redesign
However, during the strike, while few 1974 Bonnevilles were built, Trident production continued unabated. The Trident was built on the same production line as the BSA Rocket 3, at BSA’s enormous plant in Small Heath. Of course, production was never very high.
In 1975, the US DOT passed a new law requiring all motorcycles sold in the US to have left-foot shifting. British bikes had always traditionally had right-foot shifting, ‘as God had intended’. It was going to be a major engineering feat for the cash-strapped Meriden Co-Op to move the shifter to the other side of the engine. Amazingly, they got it done on the Bonneville/TR7 and it worked well. However, the Trident engine needed to be completely re-engineered to make it happen. And when they did they optimized the new design to reflect everything they’d learned over the past a 6 years of Trident production. The new engine had forward-sloping cylinders just like the old BSA Rocket 3 and, are you ready for this?, finally, finally an electric starter. Of course, it was supplied by Lucan Electrics, “the Prince of Darkness”, so it only worked intermittently.
The 1975 Triumph Trident had been completely redesigned, now with left-foot shifting and slanted cylinders, BSA-style. It turned out to be the Trident's swan song.
Triumph Trident Too Little Too Late
However, during the strike, while few 1974 Bonnevilles were built, Trident production continued unabated. The Trident was built on the same production line as the BSA Rocket 3, at BSA’s enormous plant in Small Heath. Of course, production was never very high.
In 1975, the US DOT passed a new law requiring all motorcycles sold in the US to have left-foot shifting. British bikes had always traditionally had right-foot shifting, ‘as God had intended’. It was going to be a major engineering feat for the cash-strapped Meriden Co-Op to move the shifter to the other side of the engine. Amazingly, they got it done on the Bonneville/TR7 and it worked well. However, the Trident engine needed to be completely re-engineered to make it happen. And when they did they optimized the new design to reflect everything they’d learned over the past a 6 years of Trident production. The new engine had forward-sloping cylinders just like the old BSA Rocket 3 and, are you ready for this?, finally, finally an electric starter. Of course, it was supplied by Lucan Electrics, “the Prince of Darkness”, so it only worked intermittently.
The 1973 Triumph X-75 Hurricane was Triumph's factory chopper.
1973 Triumph X-75 Hurricane
This is an interesting story. Remember that BSA suffered from corporate envy toward Triumph. When the new triples came out, BSA wanted a limited-edition ‘halo bike’ that might get buyers into BSA showrooms, and one that would outshine Triumph’s Trident.
In 1971 BSA, on the verge of bankruptcy, hires American fairing guru Craig Vetter to style the bike. What he came up with was a factory chopper, all the rage in the day. Harley-Davidson had just done it with the Super Glide. Vetter took a stock BSA Rocket 3, extended the front forks, created a whole suite of gorgeous fiberglass bodywork (his specialty), and a wild set of pipes. All three pipes ran along the right side and splayed upward at the back in a very striking fashion. The bike is just jaw-dropping to look at.
Alas BSA failed in 1972 and tried to merger with Norton-Villiers for form the new Norton-Villiers-Triumph. BSA was out and now Norton owned Triumph. Triumph inherited the project in 1972 and rebadged it as a Triumph, and released it as the 1973 Triumph X-75 Hurricane. Everyone loved the bike, but it was a very limited model with only around 1,183 made. The bike couldn't pass ever-tightening US noise restrictions with those gorgeous triple trumpets, so there were no 1974s.
If you look closely at one, you’ll note that the engine and frame are straight from the BSA Rocket 3. It’s not Triumph stuff. Again, the bike was designed and engineered on BSA’s watch and Triumph wasn’t about to re-engineer everything. So it was launched just as it is seen here, a BSA in Triumph clothing. But with BSA now out of business, they only had enough BSA parts to make around 1,000 bikes.
The irony here is that the Hurricane was meant to be BSA's poke in Triumph's eye, to one-up them (made even more ironic since Triumph created the bike and shared it with BSA). But in the end, Triumph survived arrogant BSA and turned their halo bike into a Triumph. Who poked whose eye?
Triumph Trident Year-by-Year
1972 Triumph Trident T150 / T150V
Triumph Trident Books
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