Carole Nash
Content Writer
Published: 24th June 2008

This beefy, 2.3 litre cruiser must surely be one of the most eagerly anticipated Triumph motorcycles since the Hinckley factory opened for business back in 1991.

Huge power, great styling and plenty of rider comfort all help, but this bike’s appeal can be summed up in one handy phrase; `What the hell is that?’

Roland Brown takes Britain’s biggest, boldest fashion statement on wheels for a spin.

When it was unveiled last year, Triumph’s Rocket III made a big impact with its unique look, its inline three-cylinder engine layout, and most of all with its record-breaking capacity of 2294cc. No doubt about it, size is a big part of the Rocket’s appeal. It’s a vast, eye-catching machine that produces 140bhp, along with a massive maximum torque figure of 147lb.ft, delivered at just 2500rpm.

Fast-forward to eight months later and, after a day spent riding the triple on its launch in California, I’m suitably impressed by its stunning straight-line performance. Almost everyone seems to love the big bike’s looks, too. But much to my surprise, it’s the Rocket’s good handling and rider-friendly feel that have made the biggest impression.

It has been a day of gentle cruising and arm-lengthening acceleration, including a memorable downhill blast when the Rocket charged with stomach-churning force towards its electronically limited 140mph maximum speed. More surprisingly, the Triumph has been great fun on the twistier parts of the Californian launch route, where it handled and cornered very well for such a big, heavy machine.

Back at our launch base at Sonoma, north of San Francisco, I’m sufficiently impressed to conclude that at least some of the hype is justified. The majority of British motorcyclists won’t be trading in their sports bikes in favour of cruisers just yet. But after riding the Rocket III, I’m sure that plenty of riders would get a lot of fun from a relatively laid-back bike – at least one with the distinctive style and stunning performance of the Hinckley firm’s giant triple.

The Rocket was conceived mainly for the US market, where Triumph’s existing Bonneville America and Speedmaster twins have gone down well. Cruisers account for more than three-quarters of the 650cc-plus bikes sold in the States, where the Triumph name is still popular with many older motorcyclists who owned Bonnevilles and the like in their youth. So building a big cruiser made plenty of sense.

Triumph’s design team including stylist John Mockett shaped the bike with the help of feedback from styling clinics in Los Angeles and Dallas.

Four-cylinder and V6 engine layouts were considered before the design team settled on an inline triple, which required liquid cooling due to its shielded rear cylinders. Capacity was increased to 2294cc from the original prototype’s 1500cc.

“The three-cylinder concept was accepted straight away, and the one thing that came out was that bigger is better,” recalls Ross Clifford, Triumph’s head of new model development. “They wanted the biggest.”

The DOHC, 12-valve layout results in a peak power output of 140bhp at 5750rpm, and 147lb.ft of torque produced at just 2500rpm. The height-reducing dry sump layout was adopted from the start. Service intervals are long at 10,000 miles.

The intake system uses a main airbox under the seat, and a plenum chamber on the left side of the fuel tank, feeding the injection system. The twin-butterfly layout allows the engine’s ECU to control throttle response, reducing the torque output by seven per cent in the lowest two gears, and by slightly less than that in third. The exhaust system incorporates twin catalytic converters, allowing the Rocket to pass Euro 3 emission standards due in 2007.

The engine’s longitudinal layout made it a natural choice for Triumph’s first shaft final drive. A 120-degree crankshaft design combines with a balancer shaft to control vibration, allowing the engine to form a stressed member of the twin spine steel frame. Suspension is from Kayaba of Japan.

Triumph worked with Metzeler to optimise rubber. Triumph’s designers wanted a 240-section rear tyre, much wider than the 150-section front.

The Rocket is unmistakably a cruiser but it looks like nothing else on wheels. Speed Triple type twin headlights, thick upside-down forks, and most of all the big inline engine all help. Neat touches include the under-seat tool tray plus the removable pillion seat, which mounts on a steel bracket so it doesn’t mark the rear mudguard’s paint.

Despite having the airbox underneath it, the seat is very low at 740mm. Ahead of you are the tall and wide gas tank (which holds a generous 25 litres) plus the small pair of chrome-rimmed clocks bolted to the hefty top yoke. The bars are wide and pulled back; footrests are well forward.

I’d assumed that the Rocket’s 320kg of dry weight, combined with its raked-out 32-degree forks, lengthy 1695mm wheelbase and fat rubber, would make the bike hard work at slow speed. That wasn’t the case at all, though.

In fact the generous steering lock and low centre of gravity helped make it easy to manoeuvre at slow speed, aided by the fuel-injection system, whose twin-butterfly system gave a smooth throttle response.

The Rocket certainly flies when you want it to, though. Ninety per cent of that 147lb.ft max torque figure is delivered all the way from 2000 to 6000rpm, which makes for effortless acceleration, in conjunction with the light but apparently strong clutch. The triple is especially well suited to fierce yet effortless launches away from a standstill, when the bike’s length, allied to the grip of that huge rear boot, makes it much easier to control than a typically wheelie-prone sports bike.

Once under way, the engine’s flexibility also made the Triumph very rider-friendly. There was enough vibration for a bit of character; not enough to annoy. The five-speed box shifted quite well (though it was perhaps slightly less slick than some). Much of the time I simply stuck the Rocket in top and ignored the lever. The bike felt relaxed yet always ready for a burst of extra speed.

The Triumph certainly took its chance to impress on the one occasion when I crested a rise behind two other bikes to find the road opening out into a short, downhill straight. From 3000rpm and about 60mph in top gear, I wound back the throttle and went charging past the bikes I’d been following.

Moments later I glanced down to see the speedo registering 135mph and counting, before I had to shut down and get back into the right-hand lane.

If the Triumph’s engine was impressive, so too was its response when asked to slow or change direction. The Triumph’s twin-spine steel frame is strong, and the suspension is firm enough to keep the bike under control, allowing just the occasional minor wiggle in bumpy bends. The 43mm upside-down forks, in particular, were very effective. In typical cruiser fashion the short-travel shocks transmitted bigger bumps through the seat, but in general the Triumph was reasonably comfortable as well as stable.

Ground clearance was good by big cruiser standards, and the Rocket could certainly be hustled down smooth, twisty roads at a decent pace. But inevitably the footrests touched down early by the standards of sportier bikes, and on one occasion my bike’s left peg snapped off after hitting a solid, sticking-up cat’s-eye in the middle of the road. Most owners are likely to find the cornering clearance perfectly adequate; some former sports bike riders won’t.

Few Rocket pilots will be disappointed by the bike’s stopping power. Daytona 955ie-style 320mm discs and four-pot calipers gave just the level of bite needed, and the long bike’s lack of weight transfer meant its rear disc could add some useful assistance. These excellent chassis parts are particularly important given that more than one in four Rocket III buyers is likely to have previously owned a big sports bike.

Anyone switching to the Rocket III from a much sportier machine would have to be sure that this type of bike was what they wanted. That’s particularly true because, at £11,999 on the road, the Rocket III is not a cheap motorbike. Even so, most buyers are apparently spending an extra grand or more on accessories. The long list includes various screens, luggage, footboards, heated grips, clock and fuel gauge, sissy bars and alternative seats. There are also custom paint alternatives to the standard red or black, plus various chromed parts including levers, side-panels and oil tank.

There’s certainly the potential to turn the Rocket III into a very expensive style statement, as well as the world’s largest-capacity production bike.

But the good news is that there’s much more to Triumph’s unique triple than that. The Rocket III deserves to be known not for its gaudiness or engine capacity, but for its fearsome straight-line performance, its sound handling, and especially for its impressively manageable feel.

Get Triumph motorbike insurance for the triumph rocket 111 2004.

Vital Statistics
Engine……….Liquid-cooled inline triple
Valve arrangement……….DOHC, 12 valve
Bore x Stroke……….101.6 x 94.3mm
Carburation……….Digital fuel-injection, 52mm bodies
Max Power……….140bhp @ 5750rpm
Max Torque……….147lb.ft (200N.m) @ 2500rpm
Clutch……….Wet multiplate
Transmission……….5-speed, shaft final drive
Front suspension……….43mm inverted telescopic
Rear suspension……….Twin shocks, adjustments for preload
Front brake……….Four-piston calipers, 2 x 320mm discs
Rear brake……….Twin-piston caliper, 316mm disc
Front wheel……….3.5 x 17in, cast aluminium
Rear wheel……….7.5 x 16in, cast aluminium
Front tyre……….150/80 x 17in Metzeler Marathon ME880
Rear tyre……….240/50 x 16in Metzeler Marathon ME880
Rake/trail……….32 degrees/152mm
Seat height……….740mm
Fuel capacity……….25 litres
Dry weight……….320kg
Instruments……….Speedometer, tachometer, lights for turn signals, neutral, high beam, low oil pressure, low fuel level, fuel injection failure, coolant temperature