Meriden’s Last Hurrah: 1983 Triumph TSS 8-Valve

Only 112 Triumph TSS 8-valves were imported to the U.S. before Triumph closed its doors in 1983.

Left-hand Side View of Triumph TSS

1983 Triumph TSS 8-valve.

Photo by Nick Cedar

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1983 Triumph TSS
Claimed power: 58hp @ 6,200rpm
Top speed: 125mph (est.)
Engine: 744cc air-cooled 4-valve per cylinder OHV parallel twin, 76mm x 82mm bore and stroke, 9.5:1 compression ratio
Weight (dry): 403lb (182.8kg)
Fuel capacity/MPG: 4.8 U.S. gal (18.2ltr)/52.7mpg (period test)
Price then/now: $3,800/$3,000-$9,000

Hope springs eternal, and the 8-valve TSS introduced in 1982 was Triumph’s hope for a brighter future.

Well-designed, comfortable, fast and good-handling, only 112 were imported to the U.S. before Triumph closed its doors in 1983. The reasons for Triumph’s failure are complex and reach back decades, but boil down to the Greek tragedy motif of hubris and unthinking pride. In the glory days of the Fifties and Sixties, Triumph thought its customers would always buy their products, no matter the competition. Triumph was wrong.

In the post-World War II era, Triumph found success in the U.S. with its sporting twins, while its smaller offerings brought in money at home. Up until the early 1960s, the number of American motorcycle enthusiasts was comparatively small and Triumph had no problem filling the needs of its dealers and customers. Quality control was good, and complaints were few, but the good times would not last.

As small, affordable automobiles became available in England, the market for small, economical motorcycles — then the major market in England — dried up. Triumph found itself increasingly reliant on exports and the U.S. market, to the extent that by 1966, 80 percent of Triumph’s motorcycle sales went to the U.S.

At the same time, Honda’s export effort was exploding. Honda had quickly become the largest motorcycle company in the world, mostly by selling small capacity machines to Third World countries. Unlike Triumph, Honda invested its profits in its factories. As a result, Hondas were made on state of the art equipment and featured overhead cams, electric starters, oil-tight engine cases and bright headlights.

Honda’s extensive sales efforts brought thousands of new riders into the sport, and for awhile this was actually good for Triumph and sales continued to skyrocket. Refusing to invest in its factory, Triumph trundled along, making motorcycles on the same machinery it had used since World War II. By the 1960s, the Triumph factory at Meriden was straining at its limits, building 600 to 700 bikes a week. Unable to maintain quality control, warranty costs rose steadily.

To compound these problems, Triumph was being managed by non-motorcycling executives who had no interest in listening to its American distributors, who were clamoring for better product. Triumph didn’t know it then, but the glory years were about to come to a screeching halt.

A new Triumph

The first Triumph specifically designed for the U.S. market was the 650 Thunderbird twin, which appeared in September 1949. Essentially a bored out version of the game-changing 500cc Speed Twin launched by Edward Turner in 1937, the Thunderbird eventually morphed into the T120 Bonneville. Introduced in 1959, the Bonneville became the model that defined Triumph for American buyers in the Sixties and early Seventies.

Although Triumph became a subsidiary of BSA in 1951, it had largely operated independently until the early Sixties. While the Triumph arm was making money, BSA, once the largest motorcycle manufacturer in the world, was deeply in the red and dragging Triumph down with it. BSA quit making motorcycles in 1972, and in 1973 an announcement was made that BSA/Triumph would merge with Norton Villiers and the Triumph factory in Meriden, where Bonnevilles were built, was to be closed. The Meriden workforce reacted to the news by staging a sit-in and blockading the premises.

The Norton/Triumph conglomeration struggled along for a year and a half building Norton 850s and Triumph T160 triples before declaring bankruptcy in 1975. Meanwhile, the workers at the Meriden factory formed the Meriden Motorcycle Cooperative, and with the help of friends in the British government were able to restart the manufacture of Bonnevilles at Meriden.

With cubic capacity the measure of the day, the Meriden Cooperative dropped the 649cc T120 in favor of the larger 744cc T140, first introduced in 1973. Visually identical to the 650, it was still an air-cooled 4-stroke vertical twin with two overhead valves per cylinder, but equipped with a 5-speed transmission.

Intent on returning Triumph to profitability, the Co-op steadily worked to improve the T140. A hydraulic disc brake replaced the old drum brake at the rear and the shift and brake levers were swapped right to left to comply with new U.S. DOT regulations, which, starting in 1975, mandated left foot shift and right foot brake. The U.S. market was, as ever, considered crucial to success.

The Co-op was anxious to provide a good product, and the quality control problems that had plagued previous Triumphs largely disappeared. However, there was no getting around the dated design (which was still kickstart only) and high price compared to the Japanese models. A 1976 T140V listed for $1,995, just $150 less than Yamaha’s new, decidedly more upscale and technically competent XS750 twin cam triple. Bonneville sales were not great.

Design refinements for 1978 included improved cylinder head porting for better breathing. Mk2 Amal carbs and electronic ignition came in 1979. And despite the fact the Co-op was hanging on by its teeth, in 1980 it finally managed to develop an electric starter. The bikes were handsome, but an unfavorable British pound-to-dollar exchange rate forced uncompetitive pricing and further reduced sales.

Weslake and the TSS

Triumph knew it needed to somehow make its aged twin seem more contemporary, so it turned to the idea of adopting an 8-valve cylinder head that had been designed by Weslake Engineering. Harry Weslake was a cylinder head specialist who started out working with Jaguar before going on to design performance cylinder heads for numerous Grand Prix race cars. In 1969, Weslake designed an 8-valve cylinder head and 686cc aluminum barrel kit for Triumph 650cc twins. The kit was incorporated into Rickman Triumphs, custom bikes built by the Rickman brothers using their own frame and the Bonneville engine. The Weslake head increased output to about 60 horsepower, a significant bump up from a stock Bonneville’s 52 horsepower.

In late 1979, Triumph’s director of engineering Brian Jones started work to develop the Weslake 8-valve head for production, securing tooling from Nourish Racing Engines, which had bought the rights to the design from Weslake in 1976. The new Triumph 8-valve, first shown in 1982, was a significantly redesigned engine, with a stiffer crankshaft, larger diameter bearings, and offset connecting rods to cope with a claimed 58 horsepower. The new crank was supposedly safe to 10,000rpm, compared to 7,500rpm for the standard engine. The cylinder block was new and made of alloy with pressed in steel liners, and the bores were set wider apart for more air between the cylinders.

The new head featured cast-in valve rocker boxes instead of the separate, leak-prone rocker boxes used on the 2-valve heads. Centrally located 12mm spark plugs were flanked by each cylinder’s four valves, set at a narrow included angle of 30 degrees as opposed to the 2-valve head’s 90-degree included angle. Although oil-tightness was a priority, the first batch of cylinder heads suffered from porosity problems and leaked oil badly. Ben Crossley, an engineer at Triumph at the time, claimed in an article published online at Leicester Phoenix MCC that he never experienced that issue. He did, however, blame himself for a known cylinder head leak that can occur between the cylinders, caused by incorrect tolerances he says he specified. According to Crossley, skimming the top of the barrel solves the problem.

The new model, designated TSS, was well-received by testers. It was smooth, didn’t vibrate, didn’t leak oil (the porosity problem with the early batch of heads was fixed), and the brakes were more than respectable. Not only was the TSS well-mannered, but it was reportedly capable of almost 130mph. In its February 1983 issue, Rider magazine gave the TSS an enthusiastic thumbs up, calling the new Triumph “the best ever … fully capable of being compared with the latest from across the other ocean.” Rider further praised the new engine’s smoothness. “The bars don’t tingle, the seat doesn’t shake and the footrests just, well … sit there. If you have ridden an earlier Triumph, you won’t believe it.” The smoothness was reckoned to be a direct result of the stiffened crankshaft and new, lighter pistons. Triumph planned to ship 500 TSSs to the U.S. in 1982/1983, but only managed 112. Unfortunately, the Co-op folded shortly after the TSS started production, victim of a lack of capitalization and economic fluctuations. Triumph shut its doors and liquidated in August 1983. Businessman John Bloor bought the rights to the Triumph name, and restarted Triumph production in 1990 in a new factory in Hinkley, with all-new equipment and an all-new range of 3- and 4-cylinder liquid-cooled bikes.

A survivor

The closing of Triumph did not deter the many hard core Brit bikers still riding. Many localities had a core group of enthusiasts who appreciated the excellent handling and good looks of Triumphs, Nortons and BSAs. The San Francisco Bay Area was a center of Brit bike fervor before World War II, and continued to champion Triumphs after the Meriden factory closed. One of the most active members of the many local Brit bike clubs is Don Danmeier.

Don has a collection of correctly restored British motorcycles, and one of his favorites is this TSS. “I found it in 1999,” Don says. “A private seller was advertising it and I grabbed it. It was in perfect shape with only a couple miles on it.” Given its low-volume production, some parts for the TSS are hard to find. The mufflers, for example, are special to the TSS and completely unobtainable, so when Don acquired the TSS, he removed the stock mufflers. “I replaced them with peashooters, but the aftermarket mufflers affected the performance. There was a big flat spot between 3,000rpm and 4,000rpm. Two years ago, Ron Kimball did a photo shoot of this bike, and I replaced the original mufflers for the shoot. The performance came back.” The original mufflers have since stayed on the bike.

So far, Don has put 7,500 miles on his TSS. He says he changes the oil, lubes the chain and rides it. “Joe Minton, in his Rider article, talked about rejetting the carburetors, but I tried his suggestions and can’t see that it made any changes,” Don says. The TSS came stock with a Lucas Rita electronic ignition, which cuts down the maintenance, yet Don says “all the Lucas components work.” He thinks that most problems with British electrics result from bad wiring rather than the components themselves.

Don admits to “flogging the bike a little. It handles great, has great brakes and stops on a dime. It’s comfortable and cushy to ride.” he says, adding, “the valves rustle as you ride, but it’s not the typical overhead valve sound. In stop-and-go traffic, it’s much like the pre-unit bike, it pulls from 3,000rpm. When you get out beyond the city limits, it really motors. The TSS cruises at 70mph.

“It’s a great bike,” Don concludes. “I don’t know that it would have saved Triumph — maybe if they had found financing, it would have bridged the gap.” Sadly, Triumph never did get the funding it needed to stay in the game, and the TSS remains as a reminder of the Co-op’s resolve to stay in the fight to the end, whatever the odds. MC