"... and “bastard” was the
appropriate word, because the Trident
was always a complicated
bike to produce and a
difficult one to sell
with its asking price
being almost double that
of the T120 Bonnie
which was at the height
of its popularity."

Triumph Trident T150

Buyers guide


T150V Triumph Trident and a Harrier Jump Jet. Two wonderful examples of British design and engineering. And fortunately, we've still got the Tridents. These export specification T150s were introduced to pacify the Americans who weren't too impressed with the slabbish styling of the original bikes (see further down this page). We like both, but time has a way of softening the impact of anything, doesn't it?.


1974 Triumph Trident T150 specifications

T150 variants


Bert Hopwood, Doug Hele and Trident

T150 racing from Thruxton to Talledega

Buying and riding

Ownership tips


YouTube video

Specialists & links

Triumph Trident T160 exhaust headers and oil cooler

1974 Triumph Trident T150 specifications

Type: Air-cooled ohv triple
Capacity 741cc (747cc according to some Triumph brochures of the day)
Bore x stroke: 67 x 70mm
Compression ratio: 9.5:1 (9:1 earlier)
Lubrication: Dry sump
Carburation: 3 x 26mm Amal Concentrics
Primary drive: Chain

Final drive: Chain
Clutch. Dry single plate/

Gearbox: 5-speed
Electrics: 12 volts

Ignition: Coil
Frame: Single downtube duplex cradle
Front suspension: Telescopic forks
Rear suspension: Swinging arm, twin shocks
Front brakes: 10-inch disc

Rear brake: 7in sls drum
Wheels: 19-inch front, 18-inch rear
Front tyre: 3.25 x 19-inch
Rear tyre: 4.10 x 19-inch
Dry weight: 460lb
Seat height: 32-inches
Wheelbase: 58-inches
Fuel capacity: 4.5 gallons/19 litres
Top speed: 115mph
Power: 58bhp @ 7250rpm
Fuel consumption: 35-45mpg

Triumph Trident T-shirt





T150 variants


Triumph T160 Trident

Triumph Trident T160. 1975-1977. The first T160s were on sale at a little over £1,000. Three years later, the price had shot up to over £1,400. A decent electric starter helped it keep pace with the competition. And good handling and plenty of torque helped it keep ahead of much of the pack. But it was just too expensive to produce for a shrinking market, and it was short-lived.


BSA Rocket 3

BSA A75 Rocket 3. 1968-1972. Styled by Ogle Design Consultancy, a British firm noted for numerous forays into the automotive world, the Rocket 3 (or Rocket Three if you prefer), never exactly set the world alight. Like the Raleigh Chopper (also an Ogle design), it was a little too radical for much of the market, and sales were slow. Today, these bikes are prized for their rarity and for that certain 1960s, je ne said quois. The price for a decent Rocket is usually somewhere north of a T160, and south of a Hurricane (see above and below).


Triumph X-75 Hurricane

Triumph X-75 Hurricane. 1972/1973. BSA (US) secretly commissioned American designer Craig Vetter to style this Rocket Three powered bike which was aimed very much at the American market and was intended to be badged as a Beeza. But the company was in serious financial trouble and was wound up in '72. As a result, the bike was released as the Triumph Hurricane. Around 1200 were made depending on who you believe. Dealers had a tough time selling them new. Today, an X-75 is valued at roughly double the price of an equivalent quality T160, and then some. Features include triple silencers, a fibre glass tank/seat unit, (slightly) extended forks and plenty of attitude. Guaranteed to break the ice at biker parties.

YouTube video


T150 Trident YouTube


Above: Clean, classy and competent Triumph T150 Trident. So okay, there are generally more desirable triples in the BSA/Triumph stable such as the X-75 Hurricane, Rocket Three and T160 Trident. But the humble T150 is still a contender, and is better value for money. We took this example (belonging to classic bike dealer Phil Clarke) for a spin around Kent and made a short YouTube video. It ain't much, but it ain't terrible. Check it out.

YouTube T150 Trident video


Restored T150 Trident, side view



1963: Doug Hele (Triumph development engineer) proposes a three cylinder flagship.

1968: US launch of the T150 Trident and (similar) BSA Rocket Three. Angular styling and "ray gun" silencers aren't popular, but the bikes are generally well praised and boast top speeds, under some conditions, of 125mph - although 115mph to 120 mph is more typical, largely due to manufacturing irregularities and quality control issues. Production commences in August.

1969: Tridents are on sale in the UK.

1970: Improved crankcase sealing, improved lubrication, and lowered gearing. Revised "Bonneville" look for the US market.

1971: "Ray gun" silencers are canned. New megaphone exhausts are in. Conical hub drum brakes replace full-width hubs. Indicators/turn signals are fitted as standard. Wire mudguard-stays are introduced. New warning lights are incorporated into the headlamp.

1972/1973: The T150 becomes the T150V with the introduction of a 5-speed gearbox. Conical front hubs are replaced by a 10-inch cast-iron disc and Lockheed hydraulic caliper and master cylinder. Original steering damper is deleted. Longer silencer with "restrictive" gas flow is fitted.

1974: T150V Trident dropped from the range.

1975: T160 Trident (with electric start, forward sloping engine, front and rear discs) is launched.

1976: T160 Trident dropped.

1977: A limited number of (cancelled export order) Trident Cardinals are brought onto the UK market.


Over 27,000 Tridents were built (figure includes later T160 electric-start models). Other sources quote the number as high as 45,000 bikes (possibly including Rocket 3s).


Specialists & links


Norman Hyde

Norman Hyde Ltd, Rigby Close, Heathcote Industrial Estate, Warwick, CV34 6TL

01926 49 73 75



Triumph Owners Motor Cycle Club

Got the bike? Join the club. Branches nationwide. Knowledgeable people. Big social calendar.




Unit 8, Set Star Estate, Transport Avenue, Brentford, Middlesex TW8 9HF

0208 847 1711


L P Williams



Trident Owners Club


IF LIFE BEGINS AT FORTY, then the T150 Triumph Trident is where it all kicks off, because this superlative piece of top-flight British motorcycling engineering has just entered its fifth decade and is faster, more surefooted, more reliable and better value that it ever was—or is ever likely to be.

From the moment you prod into life the 741cc, 67mm x 70mm, all-alloy engine, you get your first inkling that all the doom & gloom gossip commonly bandied around about these classic pushrod triples is long past its sell-by date. And that delicious surge you feel when you first wring the throttle heralds one of the best threesome experiences you’re ever likely to get, taking you all the way up to around 120mph—and beyond—depending on what state on tune has been dialled in on the assembly bench and whether you’re riding with your knees in the breeze, or your feet in retreat.


T150 Trident UK specification


T150V Triumph Trident. Lots of power, great sound, good handlingand increasingly acceptable "breadbin petrol tank" looks. These are great bikes loved by a select few.





Although (unsurprisingly) not as taut and sharp as its race-bred brethren, a basic, untweaked T150 or T150V is nevertheless triumphantly predictable and gives ample warning of an imminent breakaway—which you’re never likely to get even close to due to the relatively low-slung foot pegs and a grinding centre stand that’s guaranteed to set alight any roadside tinder on a hot, dry summer’s day.

That said, modern tyres and suspension tweaks have revolutionised what was once a slightly wallowy ride, while braking upgrades (for both drum/drum and disc/drum variants) have long since got all that heavy metal momentum on a short leash. Which is why even a mildly modified bike will kick sand in the faces of all but the best riders.

At low revs, the engine throbs and pulses in a manner quite unlike any other Triumph. It's a big dog straining to sink its teeth into something juicy, ideally in big chunks. By the time you hit the mid-range, the engine note takes on a hollow, anxious rasp and you get your first inkling of the real appeal of these backstreet bruisers.

At around 4,500-5,000rpm, Trident warp drive kicks in and you can quickly forget your love for British parallel twins and go boldly where lots of men have been before.

 At 85-90mph the engine isn't merely singing; it's a full blown choir filling the air with a delicious three-pronged blast of mechanical music.

There are vibes. Plenty of them. But you don't notice them on a short, fast, fixed-speed run. Or, rather, you do notice them, but you don't care. You're too busy enjoying the lusty induction scream and howling exhaust note that belongs to no other motorcycle in the world, except another Triumph/BSA triple.


T150 Trident instruments, speedometer and rev counter


T150V instruments. You won't need a rev counter or a speedometer when riding one of these. Not if you're riding it properly, that is. Just point, squirt and enjoy. Clocks are for cissies. But watch the oil light, huh?



Bert Hopwood, Doug Hele and Trident production


On longer hauls, say 120-150 miles, your fingertips begin semaphoring a signal that these vibrations will ultimately take their toll if you don't spread the power around. So you naturally look for a winding "A" road, safe in the knowledge that you can straighten whatever bend comes at you and eat up those open sections like a bulimic on a bender.

First produced in 1968, the T150s trickled off the Meriden assembly line as the bastard child of Bert Hopwood and Doug Hele, two of England’s most forward thinking engineers who rightly saw the rising multi-cylinder Honda 750-4 threat from the Far East and were determined to pre-empt it.

Which they did, if only by a few weeks.

And “bastard” was the appropriate word, because the Trident was always a complicated bike to produce and a difficult one to sell with its asking price being almost double that of the T120 Bonnie which was at the height of its popularity.



Triumph Trident primary case


A diaphragm spring clutch sits behind that cast aluminium cover. The clutch is reasonable light and transmits the power reliably. But upgrades are available if you need it, plus belt drive kits. Our advice? Stay with chain.



T150 racing from Thruxton to Talledega


The Trident also suffered numerous technical failures that were expensive and time consuming to fix. And its early slabbish “breadbin” styling was an added bugbear that prompted rapid revision in response to American sensibilities; guys who, in many respects, proved to be even more conservative than the Brits. It was amazing that the bike ever saw volume production at all.

Where the Trident excelled was on the world’s racetracks where, along with its BSA Rocket Three counterpart, the T150 trounced all comers on both sides of the Atlantic at Montlhéry, Ontario, Daytona, Mallory Park, Brands Hatch, Le Mans, Talladega and Thruxton. To cap it all, these awesome triples won the 750cc Isle of Man Production TT no less than 6 times.

Great Trident/BSA virtuosos include Dick Mann, Bob Heath, Percy Tait, Ray Pickrell, Paul Smart, Tony Jeffries, John Cooper, Mick Grant, Malcolm Uphill and Dave Nixon, each of whom found the Trident to be both challenging and exhilarating, and always a machine to be reckoned with.

In 1972, the four-speed T150 became the five-speed T150V. In 1973 a front disc brake appeared. In 1974 the T150V was dropped from the range giving way to its successor, the heavier and therefore slightly more ponderous electric-start T160 Trident.


T150 Trident electrical coils


Three ignition coils. And three sets of points too (beneath the right side engine cover, assuming your Trident is still on contact breakers). Tedious to adjust, but kinda old-worldly cool. Adjust those point at the roadside, and modern riders will stop and think you're a nuclear scientist. Tip: Fit an electronic ignition and spend your time riding, not maintaining.



Buying and riding


Today, the T150 is overshadowed both by its T160 brother and any of the BSA Rockets thereby making it absolutely the best value Meriden Triumph on the market, pound for pound.

Prices have, if anything, slipped in real and actual terms over the past few years to the point where good, honest, rough-and-ready road legal examples are still available at £2800. That was a realistic entry-level price at 2008-2009, and by 2012 the bikes rose steadily in value to around £3,500 (still entry level). But they've now dropped a little. Consequently, at 2013 prices, you'll probably pay around £2,800-£3,250 to get on the Trident ladder—and yes, we have seen a few examples at this price.

A very clean/sorted example will perhaps change hands at between £4,800 - £6,000 depending on the mods/extras/history/mileage. And that's a very fair price for one of these beautiful bikes.

There's no significant difference in prices between the T150 and the T150V. Just buy on condition, and with your eyes.

If the T150 has a weakness, it’s an expensive engine to rebuild at around £2000-£2500, and it’s heavy on fuel at around 40mpg overall. But once you turn on the gas, you just won’t care. It's a powerful, confident and comfortable bike (both solo and two-up) and has plenty of road presence for the rough and tumble of modern motoring. True, the controls are a little heavy when stationary. But on the hoof, you quickly make the necessary adjustments except, perhaps, in the heaviest of traffic.

According to Triumph, the Trident was “The most challenging example of primeval power on the road”.

But to the rest of us, it’s simply a British muscle bike at its best.


Triumph Trident Amal carburettors


T150 Trident carbs. Three springs will give your right hand a harder work-out than anything else you're likely to do during the day. Pity really, because it makes the bikes feel like harder work than they are. Either live with it, or move on. It's your call.


Triumph Trident T150 rear brake hub


Conical rear hub. Not great, but good enough unless you're riding seriously hard.


Triumph Trident T150 front wheel hub


Front disc. Early bikes came fitted with 8-inch drums. The 10-inch disc (above) and Lockheed caliper gave the Trident bark some extra braking bite. But our advice is to upgrade to a twin disc set-up if you plan to really ride one (as oppose to merely parade one).




Ownership tips


1. Good carburettor balancing is crucial, and (arguably) you will need a set of vacuum gauges to do it accurately, so factor that in. For bikes with standard Amal carbs, you'll have to modify the inlet manifolds to accept the rubber pipes from the gauges (drill and tap, or epoxy). Simple enough job for any reasonably well-equipped workshop. We have seen ready-to-fit inlet manifolds suitably adapted for Tridents, but haven't seen them lately. However, if you've "upgraded" the carbs to Mikunis or Dellortos, you should have a vacuum take-off pipe ready to use. Note that some owners feel that the vacuum gauges actually hinder balancing and prefer more traditional methods. The centre carb, incidentally, is difficult to "tickle", but extensions levers (as fitted to later models) are available.

2. Check the pedigree when buying. T150s are only as good as the last builder, and an "amateur" build may not be good enough to rectify many of the known problems with factory built Tridents, which include poor top-end assembly and poor cylinder machining - but when sorted, it's sorted.

3. The three sets of ignition points are trouble-prone and tedious to adjust. Most bikes will have been converted to electronic ignition, so check when buying. Conversion, however, is relatively simple.

4.The T150’s engine is comprised of 14 castings and ought to leak like a sieve. But amazingly, the castings are generally reasonably oil tight. That said, check carefully all around the bike particularly between the main vertical crankcase joints and gearbox joints which could result in a full engine strip.

5. All T150s are right-side gear change, so factor that in when buying - but keep in mind that even if you're used to left-side changes, you can usually adapt fairly quickly and confidently.

6. The valve gear on T150s takes a pounding. So check for exhaust oil smoke on the overrun. Oily bores are typical on non-sorted models. Oil seals on the inlet valve stems help conserve the black stuff.

7. T150 oil tanks are rubber mounted and are prone to cracking. So check regularly.

8. A clonking noise on tickover could be clutch cush-drive rubbers failing. This is a weak spot on Tridents. Relatively easy to fix, if a little time consuming.

9. Generally, Tridents consume a lot of oil - which can be reduced by fitting O-rings on the valve guides (not all owners agree that fitment is wise). Modern valves and guides, however, are a must on the next rebuild. Ditto for modern pistons and rings, and an expert rebore and hone from a Trident specialist.


4-speed 1969 T150 Triumph Trident


T150 Triumph Trident. This is how the (4-speed) bikes first appeared in 1968/1969 as realised by Ogle, the London design house that also gave us the equally slabbish, sober, and ponderous looking BSA Rocket Three (see above left). The entire T150/Rocket 3 escapade was commercially daring. But the enemy (Honda 750-4) was at the gates, and BSA-Triumph had to meet the orientals toe to toe. At Sump, we still prefer the Trident, but the Honda was a close call. Check those ray gun exhausts and get the funk out.





T160 Triumph Trident. The final incarnation of this great British superbike (notwithstanding a 4-cylinder 1000cc Triumph Quadrant prototype). Click on the link or the image to be transported to our Trident T160 quick review.

Classic bike dealers, engineers, mechanics and experts


Copyright Sump Publishing 2013/2014