CARBON-FIBRE CHASSIS, 177KW OF AUDI POWER

+ Click to Enlarge WHEN BIKERS BUILD RACING CARS: KTM's X-Bow Race has four wheels rather than two but its motorcycle ancestry is clear.

October 29, 2008

Austrian motorcycle manufacturer KTM has always had a unique perspective on automotive engineering – it's one of very few that build mostly competition machinery rather than road bikes.

At a meeting in late 2005 between KTM boss Stefan Pierer and top independent designer Gerald Kiska they noted that although the sports-bike market in Europe was shrinking there was a rise in sales of "pure" sports cars – small, light and designed purely for performance and agility.

Could KTM, with its successful off-road and GP motorcycle racing background, build such a car?

After that things moved quickly – an in-house "test mule" was built to prove the validity of the concept – now named X-Bow - and in January 2006 KTM approached Italian racing chassis specialist Dallara to build a prototype carbon-fibre monocoque chassis for a radically styled, super-quick, barely street-legal, two-seat roadster to be powered by a turbocharged two-litre Audi TFSI engine .

The concept was ready for the 2007 Geneva auto show and reaction from sports-car enthusiasts and the motoring media was so positive that KTM built a plant at Graz in eastern Austria to produce the X-Bow.

A production-ready prototype was shown only a year later at the 2008 Geneva show and the first production model was delivered on August 5. And at the end of September the first IAF-homologated GT4 Sports Light "customer racer" X-Bow rolled off the assembly line.

Right from the start the intention was that the X-Bow would be raced – the race version was developed alongside the road car, using feedback from three Dallara-built prototypes that competed in the 2008 GT4 Sports Light European Cup.

The first two cars made a sensational competition debut at Silverstone in England: first and second in class in both GT4 races ahead of a lot of more powerful – and more expensive – machines.

They did it again at Monza; one was third overall in a 50-minute rain-soaked race. After three more meetings – Oschersleben, Spa-Francorchamps and Brno – the team sealed the GT4 Sports Light championship with its three cars at the top of the points.

And at the final meeting of the season in Nogaro, France, Christopher Haase took pole ahead of the more powerful GT4 racers and went on to take overall honours ahead of team mates Dennis Retera and Catharina Felser.

The three "works racers" provided the basis for the X-Bow Race model. Most of the changes to the road car are safety-related: with steel rollover bars instead of aluminium, extra layers of zylon fibre on the sides for improved crash protection, extended mudguards and extra side-impact protection between the front and rear wheels to prevent tangling wheels with other cars.

X-BOW SUPER SPORT CUP

The X-Bow Race has a two-litre Audi TFSI engine tuned to deliver 177kW at 5500rpm and 310Nm from 2000-5500rpm. The car weighs only 825kg so claimed performance is electrifying: 0-100 in 3.9sec, 0-160 in 8.5sec and a top speed of 220km/h.

It has double-wishbone suspension all round with adjustable coil-over shock absorbers, 17" alloys and 205/50 tyres in front and 235/40s on 18" rims at the rear. KTM says its Brembo ventilated disc brakes will stop the X-Bow Race from 100km/h in 33m and from 160 in 78m.

It costs €82 900 (about R1.1-million) ex-VAT from the factory and customer deliveries are scheduled to begin in January 2009.

In 2009 KTM will launch the X-Bow Super Sport Cup – a championship for X-Bow Race owners that will be run inside existing racing series.