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- Written by Carole Nash Editor
- Created: 24 June 2008
How mad can you get? Try taking the jet engine from a helicopter, then building a motorcycle around it.
That is exactly what the American company, Marine Turbo Technologies did, creating a 286bhp, 200 plus mph monster, which runs on diesel - yes, we did just say diesel.
Surprisingly the Y2K bike weighs in at just 190kgs, which is about the same as your average big sportbike, but it is substantially longer, and you need to dial the turbine blade speed up to 20,000 revs before you can even think about setting off.
Wild looking, slightly scary, and yet useable - all round sensible fun for the speed crazed, petrol refinery and private runway owning millionaire.
Less than ten minutes into my test, and already I was in big trouble. ’What the hell speed were you doing? You could be put in jail for this!’ shouted the Daytona Beach cop, gun in his belt, as he jumped out of his patrol car and strode towards me. ’I was chasing you at 118mph and you were pulling away! Do you realise how dangerous. Wow! What on earth is that bike?
He might well ask. When I’d seen the police car’s blue lights approaching, after turning round in the road (there’s no way he’d have caught up otherwise!), I had quickly shut down the bike’s jet engine. But even without its unique high-pitched whistling noise to give it away, this long, low silver machine was clearly nothing like anything else on the Daytona streets during Bike Week.
The answer to the cop’s question is that this is the Y2K gas turbine-powered prototype, the first of a series of bikes being built by Marine Turbine Technologies of Franklin, Louisiana. The Y2K produces almost 300bhp, has a top speed of over 200mph, looks like nothing else on two wheels and sounds like... well, pretty much like the Bell Jet Ranger helicopter in which its powerplant was formerly located.
Marine Turbine Technologies (MTT) boss Ted McIntyre has built up a thriving business in recent years, based on the fact that aero engines can be used only for a certain number of hours before being retired for safety reasons. This leaves many perfectly good and very powerful gas turbine engines that face being scrapped until they are bought and adapted by MTT for projects ranging from boats and generators to a fire pump capable of squirting 50,000 litres of water per minute.
Now McIntyre and his 11-strong workforce, led by bike specialist Christian Travert, have applied their knowledge of these engines to develop the Y2K, of which a small series is being produced for sale at US $150,000 (about £100,000) each. ’When Ted approached me about the bike project he thought I could maybe adapt a Harley chassis for the engine, but I said ’No way, we’ll have to start from scratch!’ says Travert, whose bike experience ranges from African rallies to custom building.
The motor is a Rolls Royce Allison 250, essentially standard and running on diesel. ’It can use anything from normal pump gas to tequila or even Chanel No.9,’ says Travert. ’But diesel fuel burns most efficiently, so that’s what makes most power.’ That efficiency does not run to economy. ’The tank holds 8.5 gallons [32 litres], which lasts about 20 minutes on the highway.
Other numbers are very impressive. Peak output is 286bhp at the rear wheel on a Dynojet dyno, with the turbine spinning at 52,000rpm. Maximum rear-wheel torque of an equally huge 574N.m is produced when the output shaft, which spins at up to 6000rpm, is turning at 2000rpm. (The turbine turns the output shaft by gas pressure, rather than a mechanical means, so the rpm figures are not directly linked.)
Jet engines run best at a constant speed, and in helicopter use the turbine’s compressor spins at over 50,000rpm all the time, with motion being controlled by the pitch of the blades. For the prototype bike, Travert grafted on a gearbox and clutch to take drive through 90 degrees to a sprocket, and from there via a chain to the rear wheel. For the production model he has devised a two-speed gearbox with automatic transmission, which will give sharper initial acceleration.
The big lump of engine, which weighs 63kg, sits in a beefy twin-spar aluminium frame of Travert’s design and manufacture. He also fabricated the aluminium swing-arm, whose steep downwards angle from pivot to rear wheel is designed to harness the motor’s torque to keep the front wheel down under acceleration. The prototype’s wheelbase is a lengthy 1803mm and its dry weight 210kg, but the production model, with revised frame and carbon-fibre bodywork, is 28mm shorter and weighs a respectable 190kg.
Hand-made billet aluminium triple clamps hold upside-down front forks that on the prototype are from WP, and in production will be from hlins. The Swedish firm will also supply the horizontal rear shock, which on the prototype is an air unit from Fournales of France. Other high-class chassis parts include 320mm front discs and six-piston calipers from PFM. Three-spoke, 17-inch diameter carbon fibre wheels from Dymag wear Pirelli Dragons, the rear a 200/50-section radial.
Production Y2Ks will have a full LCD instrument display in place of the prototype’s conventional round dials. (Conventional, that is, if you’re used to seeing tachometers calibrated to 60,000rpm.) Like this first machine, they will also have a rear-view camera instead of mirrors. The cockpit’s small TV screen fully functioning, but hard to see in bright sunlight added to the futuristic feel as I climbed aboard and stretched across the long grey tank to the clip-ons.
The starting procedure is more like firing-up a helicopter than a motorbike. After turning on the ignition you press the starter button, which spins the turbine with a whine that rises in pitch as revs increase. Instead of releasing the starter button you keep it pressed (and the igniters inside the combustion chamber firing) as revs build, sound rising to a piercing shriek, your eyes watching the tacho creep round the dial to 20,000rpm at which point the high-pressure diesel mixture has ignited, combustion continues spontaneously, and the Y2K is ready for blast-off...
There’s no gearlever, and you can pull away without using the clutch . But for a quick getaway you have to dial in still more revs the engine remaining eerily smooth then release the clutch, at which point the bike pulls away rapidly by car, if not superbike, standards. The production Y2K’s two-speed automatic gearbox will boost speed off the line but the prototype had enough to be getting on with and once the tall-geared motor was into its stride, it was a much more exciting story.
When I rode the prototype, which has covered over 15,000 miles, mostly in development testing, it was suffering slightly from a slipping clutch caused by too many dyno runs (it’s done over 100 in total). Under full throttle the turbine immediately spun to full speed without sending all its drive to the rear wheel. But when I tweaked the throttle from 50mph onwards there was still enough power getting through to make the bike leap forward and send the Florida scenery rushing past mighty fast.
At a steady 100mph the Y2K was mind-blowing: rock-solid, incredibly smooth, and comfortable thanks to the leant-forward riding position and rearset footpegs. From that speed I was being pretty careful how hard I accelerated, as I was keen to avoid frying the clutch altogether. But after riding a couple of miles then turning round, I was cruising back at a steady ton, concentrating too much on the bike to notice that the car approaching in the opposite direction belonged to the Florida Highway Patrol.
As we crossed I realised I’d been going suspiciously fast, and glanced back nervously, to see that the cop didn’t appear to be stopping. So I rode on, speeding up a little, then slowing slightly for a long curve that the Y2K took with a very stable feel. No bike that has 26.7 degrees of rake and is over 40mm longer than a YZF-R1 is going to handle like a sportster, and the Y2K would take some getting used to on a twisty road, especially as there’s no engine braking at all. You have to use the powerful PFM brakes (two six-pot calipers gripping 320mm discs up front, plus a similar single-disc set-up at the rear) more than on a normal bike.
Despite that the turbine-bike was quite easy to ride, didn’t wobble or weave (though I didn’t get close to its claimed 250mph top speed), and felt reasonably sporty, aided by its firm suspension. As the curve unwound into an arrow-straight and traffic-free road, I flashed past the watching Marine Turbine guys and continued for a couple more miles before stopping and turning round to come back for another run.
At which point I looked up to see the approaching blue flashing lights of the police car, which had turned round just after we’d crossed, after all. The cop was very angry but luckily he was confused by the bike, hadn’t got close enough to get a fix on my speed, and didn’t know what to make of my foreign driving licence... so had to let me off with a warning. That was also a relief to the MTT guys who, having seen me ride by with the cop in pursuit, had jumped in their van and headed towards us in an attempt to prevent the bike from being impounded if I was arrested.
That brush with the law plus the slipping clutch meant that the rest of my ride was a bit restrained, and I didn’t get to sample the Y2K’s considerable potential. (MTT claim it has been timed at 168mph at the end of a quarter-mile, and has reached over 200mph in testing.) Even so, I was impressed, as much by the bike’s sophistication as by its performance. Other firms have put jet engines into cars and trucks with mixed results, but MTT’s experience has enabled them to build a bike that is easy to ride as well as fast.
Gas turbine engines put out a lot of heat, not surprisingly considering this one idles at 24,000rpm. But although the Y2K kicks out a blast of hot air complete with pungent paraffin-burning smell behind it, the rider is well insulated. Earlier in the week I’d seen Christian Travert calmly riding out of a car-park and into the Daytona Beach traffic, leaving behind a horde of grinning, gesticulating pedestrians stunned by the bike’s unique look and sound.
Despite that noise MTT say the bike will soon be certified for sale in Louisiana, and for legal use elsewhere in the States. (The position elsewhere is not so clear-cut.) The firm plans to build 10 to 12 machines per year and already has seven deposits, despite the US $150,000 price tag. That’s an awful lot of money, but the Y2K does come with an engine warranty for the life of the original owner.
’Anyone who blows up one of these bikes and lives deserves a new engine,’ says Ted McIntyre. Which says it all about what is probably the fastest, and surely the most outrageous, motorcycle ever to go into series production.
Most people have flown in a plane powered by a gas turbine (or ’jet’) engine without having much idea of how one works. Gas turbines can produce more power than a reciprocating engine of similar size or weight. But they are not normally used for road vehicles for several reasons: they prefer a constant to a varying load; are thirsty; produce a lot of heat; and turn at very high speed, so are expensive to produce.
A gas turbine engine has three main components: a compressor, which compresses incoming air; a combustion chamber, where fuel is burned to produce high-pressure, high-speed gas; and a turbine, which absorbs the energy from this gas. The turbine is used to turn the compressor, via a shaft.
The engine’s power is normally delivered through jet thrust from the hot gases (as when you blow up a balloon, then release its neck), which typically exits at over 1000mph. The turbine’s output shaft can also be used to turn a turbofan’s large, thrust-providing fan (visible at the front of an airliner’s engine), or a turbo-prop plane’s propeller or the Y2K bike’s drive sprocket.
Get your Rolls Royce Y2K insured with motorbike cover from Carole Nash.
Engine Rolls-Royce Allison 250 gas turbine
Claimed power (bhp) 286bhp @ 52,000rpm (compressor rpm)
Front wheel 3.50 x 17in; Dymag carbon-fibre
Rear wheel 6.00 x 17in; Dymag carbon-fibre
Front suspension WP inverted telescopic, adjustments for compression and rebound damping
Rear suspension One Fournales air damper, adjustments for preload and rebound damping
Front brake 2, six-piston PFM calipers, 320mm discs
Rear brake Six-piston PFM caliper, 320mm disc
Top speed over 200mph
fuel capacity 32 litres
Current price £100,000