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Bike Review - Posted 7th November 2012
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Triumph 750 Twins

Triumph's T140 Bonneville and TR7 Tiger 750s are the obvious choice for a first British classic bike. Here's why...

First off, they don't cost a fortune, so you can try an old Brit bike to see if you enjoy the experience without mortgaging the cat. Second, there are heaps of 750 Triumphs on the market at any time, so you have plenty to pick and choose between.

Production of the 750s started in 1973 with the twin-carb T140V Bonneville and the single-carb TR7V Tiger, direct descendants from the Speed Twin all those decades earlier. The first few 750s were actually 724cc but the vast majority are 744cc (76mm by 82mm) from 1974-onwards. The 750 Triumphs do everything fairly well although they tend not to excel at one thing in particular - apart, perhaps, from steering rather more sharply than some lumbering four-cylinder contemporaries from overseas.

'Known all over the world'... 1980 American Spec' Triumph T140E(S) Bonneville

The affordable Bonneville looks and sounds like a proper British bike, and makes a stab at a modern spec with five gears, indicators, disc front brake, and an electric start on ES models from 1980. T140s tend to be somewhat smoother than the preceding 650 twins with marginally more power and a better spread of torque. In keeping with the times, the gearchange lever moved to the left hand side in 1976 so they feel faintly familiar for riders of modern machinery. The rear brake changed to a disc from a drum at the same time.

By 1976, NVT were marketing the 750 as 'the bike that created its own legend.' The big Bonnie engine was 'redesigned to cope with the extra power with new and stronger pistons, bigger oil pumps, stiffer rods, and so on. All adding up to smooth, effortless Triumph power.' Reassuringly, the top end still sounds like a proper Triumph: it's not broken, they all do that, Sir.

The suspension boasted 'race bred forks to give that certainty of handling under all conditions' with two-way hydraulic damping and a sensible set of gaiters. Actually, the 750s do benefit from sure-footed and predictable steering, so the blurb didn't exaggerate too much. Mind you, it was probably going a bit to extremes to claim that the 10-inch front disc was 'massive', and few of them feel 'powerful' or particularly 'smooth' today despite the Lockheed calipers. But there are plenty of available braking upgrades if you wish to improve stopping power.

'Voted machine of the Year'... 1980 European Spec' Triumph T140E(S) Bonneville

The 1976 TR7 Tiger combined 'the traditional virtues of thoroughbred handling with a power bonus from the bigger engine. Single carb design provides miserly fuel consumption of up to 75mpg with fuss free reliability.' Like the T140, it ran at 7.9:1 compression with alloy conrods, plain big end bearings and ball and roller mains; used a multiplate clutch, triplex primary chain, welded oil bearing frame with taper roller head bearings, had a seat height of 31 inches, seven inches of ground clearance and weighed around 415lb (189kg) dry.

Electronic ignition arrived in 1979 and you would definitely want to fit a modern sparky system (there's plenty of choice available) rather than rely on the contact breaker set-up which can be tiresome to time accurately. In 1980 the Bonneville was voted 'Bike of the Year' by both weekly UK papers and was still selling steadily. The majority of the specification remained unchanged, but weight crept up to 430lb for the electric-start models and there were some tweaks - like moving the rear brake caliper away from road spray to improve its performance in the hissing rain.

There's even an eight-valve version, the TSS (which you should avoid unless you're a dab hand with the spanners and enjoy untangling top end traumas), and some attractive special editions like the 1977 Jubilee, the Royal, the luggage-laden Executive, and the extremely handsome Tiger Trail of 1981.

Triumph, resting on their laurels yesterday... 1979 Triumph Advertisement
Triumph 750s on Now...

Depending on which model you prefer you'll get a choice of single or twin discs, cast or spoke wheels, high or low bars, single or twin carb, and so on. American-spec models feature sharper styling than the slab-sided Brit equivalents but the UK bikes benefit from a full-size four-gallon petrol tank: depends whether you want the bike to go a long distance or just look spiffy… UK models had low bars, generating generations of backache, while the US model, with its high bars and peanut tank, revealed why Meriden's engineers placed the footrests where they did; it all makes sense with the high bars.

The final, Devon-built Bonnies bridge the gap between Meriden and Hinckley and feature twin Brembos on the Paioli front end but are kickstart only. They also sport Italian rear suspension and silencers and Magura switchgear - altogether a pretty package if you can find one which has had its engine carefully looked after.

'...With a great variety of tank colours'. So we put the worst one at the front...

Spares and expertise are abundant, although not all modern components are of wonderful quality: an established commercial supplier or even a well-regarded ebayer may be a better bet than an anonymous autojumble stall. There is a famous saying about repro T140 spares: it can work right or it can fit right, but you can't have both at once…

There are straightforward fixes for common faults and an array of useful upgrades, and the bikes themselves are relatively inexpensive yet are capable of clocking up big miles in modern traffic. The TR7 is easier to live with than the T140 - unless you're a dab hand at balancing carbs, of course. All are very happy at 60mph, can sustain 80mph without too much trouble and will break the ton is you ask nicely.

The final incarnation of the 750 was actually a 650: the T140 chopped down to 650 size in the shape of the single carb TR65 which was built for two years from 1981. Less than 500 were made which is a shame, because this is one of the sweetest Tritwins of all time.

Jubilee Bonnie advertised at £4250, yesterday...

Tatty 750s start at £1500, mint ones go for £4500. Two Jubilee Bonnies were offered for sale in autumn 2012: one had covered just 890 miles from new and was up for £5300. The other had done 7000 miles and the seller was asking for £4250.


Triumph Owners MCC:

Words: Rowena Hoseason
Photos: RC RChive

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