KTM X-Bow v Lotus 2-Eleven v Ariel Atom v Caterham R500: KTM X-Bow v Lotus 2-Eleven v Ariel Atom v Caterham R500

We’ve tried KTM’s extraordinary X-Bow on track, now it’s time to see if it works as a road racer. And to find out how it measures up, we’ll be bringing along a welcoming committee too…

Survival instructions, quick start guide. One, kiss your comfort zone goodbye. Two, try not to bid adieu to your arse as well. Three, or your driving licence. Four, ditch the passenger (size-zero road racers are poised on a power/weight knife-edge). Five, don’t kid yourself this is transport, the destination is always the same – your own limits. And six, you will probably fight it, but addiction is a certainty.

On the face of it, the KTM X-Bow understands this version of reality well. It may come from Austria and have a road-car pedigree precisely no inches long, but it is arguably the most extraordinary object with four wheels ever to be seen on a road and, when you switch it on, its cute, rubberised LCD instrument pod that sits between the cowls of the facia asks you a provocative question (‘Ready to race?’), the implication being that even if you aren’t, it is. The irony of this will dawn slowly, but dawn it will.

Right now, having been confronted with issues concerning the will to live by the M25 on the way to collecting the KTM in Chessington, the answer is ‘no’. Conveniently, associate ed Ollie Marriage, who’s already arrived in evo’s long-term M3, agrees to take the first 100-or-so-mile stint towards the evo Triangle in Wales while I tag along in the BMW. In fact, the M3 is just the car I need to realign my sensibilities for the job in hand – a real-world tin- (well, carbon-) top hero with formidable pace and all-round talent that simply isn’t used to having sand kicked in its face. On this leg of the journey, at least, it should keep up. In comfort. With the radio on.

Sure enough, it’s all remarkably effortless but with what appears to be just the right amount of chassis playfulness, snickety gearchange action and V8 snarl to keep the entertainment bubbling along. Unsurprisingly, given KTM’s sub 4-second 0-60mph claim, Ollie and the X-Bow are more accelerative whenever they want to be (usually out of roundabouts), but, despite what’s meant to be a 150mph top end, they seem reluctant to cruise at – what should we call it? – the unofficial national speed limit. It isn’t hard to work out why. The KTM’s all-carbon tub is low-cut and the shallow pelmet of heavily tinted plastic wrapped round its front edge hardly qualifies as a windscreen. I can actually see Ollie’s crash helmet being rocked by gusts of wind. It’s clearly a vision thing.

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From where I’m sitting, life through an M3’s windscreen has never looked this surreal. I’ve never witnessed any car attract more mass gawps and the attention of the mobile phone paparazzi than this one. Whole streets of pedestrians swivel on their heels when we drive by, as if being given split-second stage direction from a West End choreographer hidden in a shop doorway.

Even by the roofless, screenless, minimalist standards of this select sector, the X-Bow looks unique and amazing, oozing Transformer-chic with additional Origami detailing by the Japanese Manga animators responsible for Pokémon. You wouldn’t call it pretty, but the way it concentrates so many angles, slats, separate mouldings, blades of carbon and artfully exposed suspension components into a compact (but wide) four-square form lends it massive instant appeal. And, yes, the explicit functionality is very bike-like, as you’d expect from a company best known thus far for its two-wheeled products.

It’s just as hard not to drool over the spec. Officially the four-cylinder 2-litre turbo FSI engine from Audi that sits just behind the driver in the immensely strong carbonfibre tub develops 237bhp, but we’ve been tipped off that this newly landed demonstrator is running closer to 300bhp, which is perhaps as it should be. The X-Bow weighs just 790kg, but that’s still around 250 kilos more than a Caterham or Atom. Add another 200kg of downforce from the aerodynamics at 124mph and it’s clear that if it wants to escape the orbit of merely very fast cars, it needs the big numbers from the engine room. Whatever the output, it reaches the tarmac via the six-speed manual gearbox that comes with the engine (a paddle-shift twin-clutch transmission will be a future option) but without any ESP or traction-control nannying. No ABS, either. Mindful of the uncompromisingly hardcore market the X-Bow is entering, KTM wouldn’t dare.

With a tad over 100 miles to go to Denbigh according to the M3’s satnav, we refuel and swap seats. Ollie hands me not the key fob (only its presence is required to activate the engine start/stop button, so it’s sat in the passive dock just behind the gearlever) but the button-festooned F1-style detachable steering wheel (an extra £931). People in the car park are watching. Cool.

I should feel apprehensive, but something about Ollie’s appearance eases the tension. He seems serene rather than shattered, and reckons that, without the head pummelling from the wind, the X-Bow would have been as comfortable and relaxing a car in which to cover the distance as a Porsche Cayman.

It’s true. The automotive manifestation of an as-yet-undiscovered venomous and bad-tempered tropical bug – probably one with razors for wings and acid for blood – turns out to be, on ordinary roads with plenty of traffic at least, as user-friendly as an Apple Mac operating system. From the moment I climb into the cabin via the flimsy-looking (but actually 200kg weight-bearing) carbon sill to rolling up behind John Barker parked in the Ariel Atom at the appointed devil’s playground in North Wales, the X-Bow’s toll on my nervous system has been minimal, even if it takes a few seconds to re-adjust to a world that looks crisp and stable rather than jagged and blurred.

This is both good and slightly worrying. Good in the sense that KTM’s efforts to produce a truly useable race car for the road have paid off. It rides beautifully; everything just works. The cockpit is simply a masterpiece, the quality of the build and finish sublime for this type of car. And if the driving position at first seems a little odd – slightly higher and with the steering wheel, although adjustable, closer to your chest than you’d expect – the effectiveness of the fixed Recaro ‘seats’ (essentially slabs of moulded foam stuck to the tub at strategic points) and the adjustable pedals is undeniable.

The worry is if all this civility refuses to step to one side and allow a meaner dynamic demeanour to emerge on the Triangle. No time like the present, then, and the X-Bow is probably the perfect car for an acclimatisation lap. In fact, I’m not sure I can remember the breathtaking sweeps and turns of these roads ever passing so swiftly and with less drama. It feels like the fundamentals have been nailed with a compressed-air gun, and given that Loris Bicocchi did the chassis set up – other credits include the Bugatti Veyron and Pagani Zonda – perhaps it’s no surprise. No one could claim that the X-Bow isn’t a deeply impressive sports car that Ferrari and Porsche drivers would do well to think twice about tangling with. It’s seriously and effortlessly quick, properly stuck down, remarkably easy to drive and, well, strangely underwhelming.

The muted character of the turbo engine doesn’t help. Throttle response is oddly gentle unless the turbo is spinning hard and there isn’t a point where the shove in the back feels anything more than solid and sustained; the thing never ‘goes feral’, never truly bears its fangs. With the all-too-necessary lid on, you can’t hear it anyway, and its delivery is so linear you tend to end up changing gear purely on the red shift-light located at the top of the instrument pod. The gearchange isn’t exactly a marvel of economy, either. Although its action is light and positive, the throws are family hatch long and feel incongruously ponderous in a superlight road racer. That said, such is the quantity and spread of torque (229lb ft from 2000 to 5500rpm, though we’re guessing a bit more for this one) you can stick in fourth on a twisty country road and still suck leaves from the trees.

With the workload of a decently challenging road stretching out into the distance, it’s at least easier to appreciate why the steering wheel is situated where it is. Weighting is quite heavy at low to medium speeds, to the extent that much of the detail feedback you sense is there is masked, and you find you need the upper-arm leverage to feel completely in control. Push harder and it all starts to fall into place. Turn-in sharpens, the helm starts to communicate with some sensitivity and finesse and you can feel the KTM pivoting around your hips, rather like a Mini Cooper S. Of course, the g-forces are much higher, especially as the speed builds and the aerodynamics work up some downforce (KTM claims 1.5g can be achieved on road tyres), but playful as the chassis is in the neutral/oversteer transitional zone, let things get too out of shape and the momentum of the engine will take over and you quickly discover there isn’t enough steering lock to gather it all up. Yet – and for better or worse, this seems to be the X-Bow’s defining characteristic – the sense of drama and excitement is much less heightened. Yes, even than in the Mini. As Barker puts it after a lengthy strop a little later on: ‘In terms of what it does and how it deals with different road surfaces, it’s outstanding. It takes out more surface wobbles than some “proper” cars, allowing huge speed to be effortless. It’s very progressive when it goes, or locks a wheel. But perhaps the baby has exited stage left along with the bath water. Cars like this are about excitement, a quick hit of adrenalin, and I think this is too good, disguises speed too well.’

IF ANY CAR IS DESIGNED to provide some perspective on the KTM, it’s the sublime union of 2-litre supercharged 300bhp Honda Civic Type R engine and pencil-thin, open-lattice tubular steel fuselage that is the Ariel Atom 3 Supercharged. In fact, the word ‘antithesis’ springs to mind, which is faintly ridiculous when you consider that both cars are pitching for exactly the same kind of customer. But to any objective observer, it’s the Atom that would appear to have spanned the distance between bike and car in the smallest number of moves. And it’s the Atom that comes with the golden track record. Fresh from a 0-100-0mph shootout with another magazine where, once again, it dished out a drubbing to all comers (11.5sec), its reputation as the only car superbike owners consider as a credible, four-wheeled alternative looks rock solid.

The fact that, with a slim-ish driver on board and a low fuel load, the Atom is one of the few cars in the world that can duck below 3sec to 60mph and 7sec to 100mph must help, but it’s the gale of sensations it brings to the process that makes it unique, the shattering contrasts it can deliver in a fraction of a second. After the comparatively fortress-like X-Bow, everything about the Atom is sinuous and dainty and, in the case of the wafer-thin seats, worryingly flimsy. The feeling of being exposed (to the elements, unsuspecting flying insects, danger) jumps by several orders of magnitude. A proper windscreen has just become an option.

As I drive gingerly out onto the Triangle, even the thought of going fast in a structure so spidery seems vaguely ludicrous, but as I chunter up through the first few cogs of the six-speed gearbox, its character is benign, almost languid. In fact, the gearshift and clutch feel slightly rubbery in a strangely cuddly ‘would I hurt you?’ kind of way.  It’s a masterful deception. On the first sniff of a decent straight I shift down into third and give the throttle a cautious but meaty push. I might as well have been struck by a bolt of lightning. The Atom feels instantly, overwhelmingly, paralysingly rapid, insane supercharger thrust and seemingly zero inertia piling on speed so quickly I almost choke on my own incredulity. But that’s the fastest Atom’s thing. You know that until you make the necessary mental and physical adjustments – essentially concentrate like hell but try to relax – it will wrench you from your customary frames of reference on a rip tide of unbridled horsepower and ask big questions about your commitment.

And this is the crucial difference between it and the KTM. The X-Bow’s manners are keen to flatter, all-but guaranteeing that your heart won’t end up in your mouth. The Atom, which has a much more softly sprung and reactive chassis, forces you to face up to the consequences of ill-judged actions, makes you worry that a few millimetres too much throttle, a momentary lapse of steering finesse and failure to accurately read the road surface might be punishable with genuine danger. ‘Can’t think of many scarier or more intimidating cars than the hottest Atom,’ reflects Ollie after a lap of the Triangle. ‘Everything is about the engine and how much of its power you can deploy at any one time. But when you do readjust, it’s actually great fun to drive.’ Barker concurs: ‘It feels much faster and more frantic than the KTM and so much more alive. You have to decide how fast it goes, when and how much to apply the throttle, mindful of what the front and rear are telling you and how confident you are at predicting how the upcoming corner/curve/bumps/surface will affect the tiger you’ve got by the tail. Manic power; sounds like an 18,000rpm buzz saw; total traction; never a dull moment.’

But there’s an even louder, angrier sound echoing through the forest, as Henry Catchpole and an R500 Superlight arrive in a hurry. No group of lightweight road racers would be complete without the granddaddy of them all and, in its latest R500 evolution – with an almost demonically rorty 1999cc Ford Duratec engine developing 263bhp and 177lb ft in place of the old K-series unit – its 528bhp per ton, dinky 13in rims and glove-fit slim cockpit promise peerless entertainment.

Henry’s got some KTM/Atom homework to be catching up with, so I slip behind the wheel (removable like the KTM’s) while the big, shiny side exhaust’s still crackling. Getting in is like lowering yourself into a canoe. Step on the seat then slide down straight-legged. Lateral support isn’t provided by the seat but the side of the tub (wearing thinner panels than ever before) and the transmission tunnel. The fit is zero-tolerance snug.

There’s a new dash with a plethora of silver push buttons. Starting is keyless: just push three of the buttons together to wake up the ignition, then re-push the one under your thumb to start the engine. It barks into life, the sidewinder exhaust snorting loudly. Snick first gear with the ultra-short-throw shift and burble off towards the Triangle. Short shift into second, then third. There’s bags of grumbly low-down urge – the high explosives are kept the other side of 3000rpm – but always the first thing that hits you with a Caterham as you move off from rest are the minimal movements required to drive it. The steering’s sensitivity feels almost supernatural; gentle curves and kinks are dispatched with little more than the power of thought, tighter bends require just a modest roll of the wrists.

But a big old prod of the throttle pedal is needed to rouse the R500’s mighty kick. Come 4000rpm, though, and that old cliché ‘all hell breaks loose’ has never seemed more apt. The reflexive slug of acceleration from there on is as epic and thrilling as anything you’re ever likely to sample on four wheels. Can the Caterham live with the Atom in a straight line? Just. And it feels heroic doing it. After the fat, torque-rich delivery of the KTM and the inertia-less rampage of the Ariel, the R500 gives the impression that it’s having to work a lot harder, a force of nature bludgeoning its way to big speeds and ultimately imposing its will as the bluff nose and flat windscreen smash through the wind.

Of course, the protection afforded by the screen means you don’t have to wear a lid and that makes the aural experience all the more intense. On the snakier sections of the Triangle, though, it simply scores by being more engaging than the X-Bow and less intimidating than the Atom. Henry, who’s spent most miles behind the wheel of the Caterham, puts it best: ‘Its size is an advantage, but you wear it more than the others and the front-engined, rear-drive layout feels just right. You can be mid-corner and sliding but, whereas you’d be concentrating on gathering it up in the KTM or Atom, it feels so intuitive in the R500 that you’re simply correcting without thinking and already looking up the road. Come over a crest and there’s the confidence to let all four wheels leave the ground even if you’ve got to turn as soon as you land. The R500 feels like it’s had any last residue of slack sucked out of it.’

And were the contest to finish now things would indeed be looking rosy in the Caterham camp. But, although absent so far, there’s one more car to go. Without requiring too much persuasion, John Lamb from Lotus has driven from Hethel to meet us in the very 2-Eleven that so impressed us on eCoty 2007 (evo 112), and he confesses he’s had a ball. The bad news is we’ve got the supercharged, Elise-based trackday special for four hours tops before he has to leave with it. But, as we’ve all driven the KTM, Atom and Caterham, we can concentrate on the Lotus.

Its effect on the day’s proceedings is profound. First, and most obviously, it has a conventional body with glassfibre panels bolted (rather than bonded) to a chassis that mates the modified cabin section of a mk1 Elise (with higher and stiffer sills than the latest model) with the latest Elise/Exige rear subframe. Then there’s the supercharged 1.8-litre Toyota engine from the Exige 225 Cup. It develops 252bhp at 8000rpm and while, as the 2-Eleven weighs 670kg, the resulting power-to-weight ratio of 382bhp per ton might not be in the Atom/Caterham league, subjectively it doesn’t feel that much slower and seems to have a slight edge over the KTM.

But that’s too stark a picture. On the Triangle, the 2-Eleven is simply sensational. Unlike the Atom, it doesn’t demand the delicate touch of a master watchmaker and the resolve of a fighter pilot to exploit to the full. But neither does it make the acquisition of serious pace as undemanding as it is in the X-Bow. Instead it seems to shift the whole business into a different register, with crisper edges, finer tolerances and more detail. The upshot is that it feels the lightest car of all, the most precise, the one in which it’s easiest to change direction and wipe off speed. As Henry comments, its front end feels as if it’s made out of helium.

As I set off for another lap, that’s where the Lotus focuses most of my attention. After the others, the steering and brakes feel completely devoid of the meatiness I’ve become used to. But, as in an Elise, acclimatisation uncovers a wealth of light and shade. It applies to the gearchange, too: featherlight but with a peachy shift quality.

The cabin is even more spartan than an Elise’s but just as spacious. There’s no windscreen or doors, and the tiny tinted Perspex aeroscreen is just as useless at deflecting the windstream over your bonce as you’d expect. In fact, the Lotus is the worst of the lot in this respect. At times it feels as if my head is being pulled one way then the other by giant magnets.

Also familiar is the way the front of the car feels so nailed and so readable – only more so. It inspires simply stacks of confidence and allows you lean on an exceptionally grippy, poised chassis without fear of any unexpected nasties. This makes its dynamic proposition similar to the KTM’s but, as John Barker later points out, it’s all a matter of execution: ‘In the others you’re bothered about what the back is up to, how it’s reacting to the combination of road and power, but in the 2-Eleven it’s the front that monopolises. It deals with the road with similar aplomb to the X-Bow but there’s a clarity, a purity to its steering that makes it involving and compelling.’

It’s hilariously fast in a straight line, too, though its blown engine seems rather pale and uninteresting next to the Atom’s. By the time the Lotus has to head back, though, it’s made its point and, within the context of this group, it’s more powerful than it could ever have been at eCoty.

THE KTM IS THE BIGGEST casualty, its ‘speed without consequence’ pitch being blown apart by the Lotus, which outmatches it for effortlessly acquired A-to-B pace but is vastly more engaging and satisfying to drive quickly. The X-Bow is several shades of wonderful but part of the spectrum is missing completely. As Ollie concludes: ‘Where’s the constant stream of information? The driving experience simply isn’t as memorable as it should be. It rides placidly and capably, but never challenges the driver, never delivers the visceral, seat-of-the-pants thrills that the Caterham and the Atom serve up so ably. The end result is a car that’s a long way from having the bite and charisma of its British rivals.’

The Ariel Atom, on the other hand, is more or less immune to attack, even from the 2-Eleven. If it’s a challenge, a massive adrenalin hit and the kind of acceleration you never really get used to that floats your boat, there is no substitute. It’s the four-wheel superbike that the KTM, ironically, so clearly is not.

In the end, though, the Caterham most ably lives up to the best-of-all-worlds ideal, combining all-but-dammit the Atom’s acceleration with an intimate, engaging and fabulously biddable chassis, heaps of charisma and a degree of practicality – windscreen, roof, boot (of sorts) – none of the others comes close to matching. A true original and still the king.

Extra Info

What's the X-Bow like on the track?A few things should be taken into consideration when looking at the lap time set by the X-Bow. Tyres are the first, because the KTM wears very road-orientated Michelin Pilot Sports. The Caterham and Atom both run on much slicker treads with obvious benefits. The second thing to bear in mind is that we left the KTM’s adjustable suspension in road trim. Why? Because it’s a slippery slope if you start adjusting cars specifically for the track, so we treat all cars the same: we don’t mess with their set-ups.

The KTM was quite a handful around the Bedford Autodrome’s West Circuit, largely due to the position and power delivery of the engine. As the turbo comes on boost it lights up the rear wheels and sends the car sideways if you’re in a corner, then mid-engined momentum steps in to compound the problem. It’s quite a balancing act – particularly through the tight Bank corner – and it’s easy to get too far out of shape and lose chunks of time.

The oversteer could be fun when you’re not going for a lap time, but the brakes wouldn’t be. You simply don’t get anything like enough feel through the pedal and you end up listening for the chirrup from the tyres to let you know when you’re on the point of lock-up.

All of the above would lose the KTM some time compared with an R500, but the clincher is that the X-Bow just isn’t as fast in a straight line, as you can see from the graph on the right.


 Ariel Atom S/CLotus 2-ElevenKTM X-BowCaterham R500
EngineIn-line 4-cyl, superchargedIn-line 4-cyl, superchargedIn-line 4-cyl, turbochargedIn-line 4-cyl
LocationMid, transverseMid, transverseMid, transverseFront, longitudinal
Bore x stroke86 x 86mm82 x 85mm82.5 x 92.8mm87.5 x 83.1mm
Cylinder blockAluminium alloyAluminium alloyAluminium alloyAluminium alloy
Cylinder headAluminium alloy, dohc, four valves per cylinder, iVTECAluminium alloy, dohc, four valves per cylinder, VVTL-iAluminium alloy, dohc, four valves per cylinder, variable valve timingAluminium alloy, dohc, four valves per cylinder
Fuel and ignitionElectronic engine management, multipoint fuel injectionElectronic engine management, multipoint fuel injectionElectronic engine management, multipoint fuel injectionElectronic engine management, multipoint fuel injection
Max power300bhp @ 8200rpm252bhp @ 8000rpm237bhp @ 5500rpm263bhp @ 8500rpm
Max torque162lb ft @ 7200rpm179lb ft @ 7000rpm229lb ft @ 2000-5500rpm177lb ft @ 7200rpm
TransmissionSix-speed manual, rear-wheel driveSix-speed manual, rear-wheel drive, electronic traction controlSix-speed manual, rear-wheel drive, limited-slip differentialSix-speed manual, rear-wheel drive, limited-slip differential
Front suspensionDouble wishbones, push rod operated coil springs/damper unitsDouble wishbones, coil springs, adjustable dampers, anti-roll barDouble wishbones, push rod operated coil springs/damper unitsDouble wishbones, coil springs, dampers, anti-roll bar
Rear suspensionDouble wishbones, coil springs, adjustable dampersDouble wishbones, coil springs, adjustable dampers, anti-roll barDouble wishbones, coil springs, dampers, anti-roll barde Dion axle, lower A-frame, Watts linkage, coil springs, dampers
BrakesVentilated 240mm front discs, solid 240mm rear discsVentilated and cross-drilled discs, 288mm front and rear, ABSVentilated discs, 305mm front, 262mm rearVentilated 254mm front discs, solid 228mm rear discs
Wheels7 x 15in front, 8 x 16in rear, aluminium alloy7 x 16in front, 8 x 17in rear, aluminium alloy7.5 x 17in front, 8.5 x 18in rear, aluminium alloy6 x 13in front, 8 x 13in rear, aluminium alloy
Tyres195/50 R15 front, 225/45 R16 rear, Yokohama Advan A048195/50 R16 front, 225/45 R17 rear, Yokohama Advan A048205/40 R17 front, 235/40 R18 rear, Michelin Pilot Sport175/55 R13 front, 205/55 R13 rear, Avon CR500
Weight (kerb)550kg670kg790kg506kg
0-60mph3.3sec3.8sec (claimed)3.8sec (claimed)2.9sec (claimed)
Top speed155mph (claimed)150mph (claimed)137mph (claimed)150mph (claimed)
Basic price£34,500£40,945£49,482£36,995
On saleNowNowNowNow
evo rating5545

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