Buying guide – Triumph TSX

An American-friendly, 750cc Triumph twin with electric start – what’s not to like?

SOME OF THE best Triumph pushrod twins to use today emerged just as the Meriden factory slipped towards oblivion. The Tiger Trail is now one of the most sought-after twins, along with the TR65 Thunderbird. The eight valve TSS was supposed to have a top speed of more than 120mph, with an anti-vibration frame in the works.

One of the very last great motorcycles out of Meriden was the TSX, a factory custom that could have done great things. It followed the principles that the Japanese were establishing for factory customs. The irony being, of course, that those customs were created in the first place to follow the lines of the US export Bonneville.

Triumph and BSA had long realised the value of the American market for their products and in the early 1970s had built bikes specifically for it, like the X-75 Hurricane triple and to a lesser extent the 500cc Trophy Trail/Adventurer. The T140D, a classy Bonneville in black and gold, had been another bike designed for the US buyer. A range of issues meant it wasn’t a success Stateside. Road testers felt the T140D needed lower handlebars and a flat seat. Heavy rain in the US was felt to have caused poor a spring sales season and the T140D came at a price that was uncompetitive compared to Japanese models.

Meanwhile a US dealer in Pennsylvania, John Monaco, had created his own chopper-styled Triumph, which some buyers thought was a factory model. It had a look that hasn’t aged well, with a square headlight, an angular and bulky seat and a lowered rear suspension. This bike was the inspiration for a design by Meriden’s Jim Barclay and, dubbed the Triumph Bonneville Phoenix, had been shown at the Earls Court show to mixed reactions.

Brenda Price, the head of Triumph Motorcycles America, was keen on a US custom model and had championed the Phoenix. She was ready to hand over the reins to Wayne Moulton, a former boss at Kawasaki, who had created the Kawasaki Z1000LTD and Z650SR factory customs. He had re-joined Triumph Motorcycles America in 1980 having last worked with the company in 1964. Wayne Moulton looked at the Phoenix and then came up with his own concept, junked most of John Monaco’s bodywork, refined the frame alterations to make them less obvious and fitted cast wheels.

TSX HITS THE MEAN STREETS

Moulton’s creation became the TSX and was originally supposed to be given the TSS engine. The prototype was sent to the UK, where it was judged to be just what Triumph was looking for. Triumph produced it in a style that was virtually unchanged from Moulton’s concept – a condition Moulton insisted upon. Unlike his work at Kawasaki, where development money had been available, Wayne Moulton had been forced to use off-the-shelf parts from Triumph stock, and bargain basement bits from other manufacturers’ over-production, such as petrol caps made in Italy for German mopeds. Even so, Wayne Moulton felt the TSX was his favourite bike – and as payment for his efforts he got to keep the first to come off the production line. The petrol tank was a modified export tank with the filler cap relocated to the middle and with one fuel tap deleted, using a balance pipe at the front to transfer fuel from one side to the other. The short front mudguard was created by getting a T140D item and chopping two inches off the rear, then painting it. The rear mudguard’s substantial trimming required a relocation of the rear light mount, but for UK market a plastic extender had to be fitted to match the number plate. In the US buyers just took this off and threw it away. The front indicators were rubber mounted and attached to the bottom of the fork shrouds, but the vibration often made short work of these and they sometimes ended up being relocated on the headlamp brackets.

The TSX used the TSS bottom end, which was a refined and toughened up version of the original T140 item. This was used with the stock Bonneville top end and fitted with the Bing carburettors also used on the Executive Bonneville – making for as good a 750 Bonnie engine as you could get.

Short megaphone-style slash-cut silencers looked good, but to meet US emissions regulations – a challenge all manufacturers were struggling to cope with – these silencers were restrictive and limited performance. By 1982 American buyers weren’t really buying Triumphs for their top-end performance and had their highway speed limited to 55mph, so lack of power wasn’t an issue. The old balance pipe at the cylinder head was finally changed to one mounted under the engine, an idea borrowed from Craig Vetter’s TT Bonneville, and the down pipes were markedly fatter.

The handlebars had a new profile, the TSX bend, and their height was midway between the fullwestern bars the US press had disliked and the semiwestern bars used on the police bikes. These were later used on 1982 US-market Bonnevilles.

The back wheel was a 16 inch seven-spoked cast wheel as was the fashion for a factory custom using a US-made Morris Mag. These were almost the same wheels fitted to some Harley-Davidsons, and on some TSX models the Harley wheels were fitted as that

“These were almost the same wheels fitted to some Harley-Davidsons, and on some TSX models the Harley wheels were fitted as that was all Triumph could get.”

was all Triumph could get. Although the rear wheel was smaller and fatter, the gearing remained the same. The chain guard was chromed. Fitting the fat wheel did require a few modifications, with the swing arm slightly widened and the frame modified as the engine had to be offset by around a quarter of an inch to make everything line up. On the front was a 19 inch seven-spoke Morris. The TSX had the new abbreviated triangular side panels and came in red, with stick-on red, yellow, and orange decals, the red scheme later joined by a black paint job. This was something of a departure from hand-applied pinstripes and was considered garish by many, but compared with the eyeball-melting paint jobs of many far-eastern rivals of the time the look of the TSX was positively restrained. There was a stepped seat too, to emphasise the pseudo-custom lines. So even though the frame was lower, the seat remained the same height. To make things lower the bottom rear shock mounts were moved back by a few inches. The Bing CV carburettors were as fitted to BMW twins of the period and were a bit of a squeeze. These were another concession to meet emissions regulations but did have tendency to leak and for the floats to get stuck, so turning the tap off and running them dry was a common procedure. TSX models for the US market were different in having leaner running Bings and a decal on the rear mudguard saying so; a locking petrol cap as standard, a different engine/frame date code system with the

frame code stamped on a riveted metal plate. The usual US spec lights-on ignition, right hand dip headlamp and Veglia 85mph speedo were also used.

In a radical move the TSX was built without a kick start as standard, using the electric start system that graced the late top-of-the-range Triumphs. Recalling the chequered history of British electric starts on the Norton Commando and T160 Trident, Triumph went all out and fitted a substantial mechanism involving a starter believed to come from a Reliant car. Even so, the sprag clutch could still give trouble, especially if owners didn’t keep the battery in top condition. A kickstart was available as an optional extra, which most buyers went with. Germany’s importer Wüst Bros offered the electric start as an option as its customers expected to kickstart a British bike.

SEVENTIES STYLE

Because of the fatter exhaust system, the kickstart had to be attached as close as possible to the end of the kickstart shaft so it cleared the silencer. The TSX also looked back to the early 1970s with wire headlamp brackets, similar to those fitted to the very first oil-in-frame 650, though thankfully these were less prone to fracturing thanks to thicker steel rods rather than wire. The shocks on the prototype were expensive US-made S&W items but cheaper Paioli shocks were used on production models, as opposed to the Marzocchis on the TSS. The rear Lockheed brake caliper had been repositioned, sitting above the swing arm rather than below, and the rear master cylinder was now a Brembo. This too had been relocated and was easier to get at than the old Lockheed unit. You could request a second front disc. Struggling with parts supply meant different discs, some four-stud and some five-stud, were used depending on what wheels and discs Triumph could buy. Lockheed calipers were still used front and rear. The Bonneville followed the lines of the TSX for the final production year at Meriden with a machine that was near identical to the TSX but with more conventional spoked wheels and the rear drum from the TR65 Thunderbird. The TSX was one of the more expensive Triumph twins in the range, costing $3695 in the US. The price was a killer in Europe too. In Germany, it cost upwards of 10,000 DM – 3000 more than its rivals, the Kawasaki Z750 LTD and the Yamaha XS650 Special. There were further refinements planned for 1984, even though the factory had by this point stopped making motorcycles. An optimistic sales brochure listed the standard model as a TSX4, indicating four valves, A TSX 8 with the TSS eight-valve engine was also listed, which was the original plan for the TSX. The TSX might have secured a brief renaissance when Triumph manufacture was taken on by Les Harris in Newton Abbot, but after building a prototype with the stronger TSS/TSX bottom end, it was discovered in the licensing agreement obtained from the owner of the Triumph Harris were only able to build bikes with the original Bonneville bottom end.

ERUM WAHEED IS a TSX owner and knows more about oil-in-frame Triumphs than almost anybody. He says: “It’s like a factory bobber before there was such a thing. you’re sitting lower in the TSX, a little hunched even – it’s not a behemoth of a bike – rather than sit-up-and-beg. It feels funky and unconventional as if you’d slotted a big motor into the frame of a 250cc bike. “On the TSX you’re sitting lower and more ‘in’ the bike rather than ‘on’ it. I ride my other Triumphs with their conventional sit-up style and the difference to the TSX is marked. I could happily put my feet forward on highway pegs with the TSX such is its riding position.” What are the best things about the TSX? “The motor is strong in performance and presence both visually and audibly. The styling is distinctly American West Coast with plenty of chrome and polished alloy and a gloriously loud, eye-catching, happy colour scheme and fat rear tyre. “If you like a custom style seating position, you’ll enjoy this. My passengers love the generously proportioned passenger seat. That fat rear tyre must help. “Brakes were excellent, and a double front disc was an option and the electric start was the latest and last upgrade of Meriden’s system so it’s as good as it could be. “The Bing carbs are something you love or hate. I love their pick-up and smooth sophisticated performance. “American ones do tend to be low mileage but while their condition varies, invariably they still have the raised white lettering tyres. “Finally, it’s the bike everyone says is their favourite. True, some gents prefer the practicality of the Tiger Trails and I love the understated TR65 but Joe and especially Josephine Public loves the TSX: no question.” No motorcycle is perfect, so what does Erum think we should watch out for? “The brittle plastic top shrouds on the Paioli rear shocks can crack as the springs compress and release. Buy the superb metal alternatives to release your spirited use of the bike. “I’d also say the Bing carbs are sensitive to impurity but it’s worth it as when on song they’re wonderful. Availability of parts unique to the model is hard and fracturing indicator brackets (a curable but not uncommon problem) are best repaired and the whole part re-chromed instead of waiting for the part to turn up. “There’s really nothing else unless you fear the Meriden electric start system. Parts for this British miracle are available but not cheap so, if you’re a regular rider, kickstart it instead when and while you can. “If you want modern raised white letter (RWL) tyres then you’ll struggle as they’re out of fashion and hard to find if they’re even made now. Certainly, OEM manufacturer Avon isn’t doing them. It’s not a big problem if you’re a rider though: their Roadrider tyres are lovely if non-RWL alternatives. “I had a unique problem with my centre stands twisting to the extent that Reg Allen’s fitted a gusseted police centre stand. Maybe the reproduction centre stands were part chocolate or maybe it was just me, as no one else had reported this problem!” Thanks to Erum Waheed, Morgan Rue and the TSX Facebook group for their help with this article