We get to ride some mad machines at Bikerworld, but this is probably my maddest yet. Supermotos are track bikes, and why anyone would want to ride one of these things on a public road is beyond me. But hey, people do, and this KTM 640 Duke is one of the most popular.

The supermoto craze started when some wag decided to bolt little fat road wheels into a motocrosser a few years back, and then found the resulting beastie could be drifted sideways in bends and ridden in a thoroughly hooligan manner. One or two manufacturers picked up the ball and ran with it, and the 640 Duke has been setting the pace since it was launched on an unsuspecting world back in '94. A major re-vamp in '99 saw the bike upgraded to keep pace with young pretenders like the CCM R30 and MZ Baghira.

And if you're thinking minimalist, they don't come any more minimal than this. An engine, a pair of wheels and, erm, thats about it folks. What little else there is attacks the world visually with outrageous orange and black graphics - this is one bike that will get you noticed. It's a funky looking middleweight with a liquid cooled four stroke single lump, all fronted by a twin lamp nose fairing that looks like it's come straight out of Terminator 3.

Starting a supermoto can present a challenge in itself; the Vertemati I rode before the Duke had only a kickstarter mounted on the left and swinging forwards. Upside down, back to front and oddly left handed. And struggling to turn over a high compression single. The 625cc single cylinder engine in the Duke does have an electric start, which is quite a relief as it also has its kickstart on the wrong side. But once its started you have 50 brake horsepower in a package weighing only 145 Kg. Mad and madder.

This bike is the original urban terrorist for wheelie and stoppie kings and isn't the slightest bit practical. Thank god then, that some manufacturers are still prepared to build such anti-social devices and sell them as road legal. The Duke really is a top adrenaline pumping wheeze. If only I was ten years younger and two stone lighter, maybe I could discover wheelie heaven too.

On the road its light and quick, as you'd expect, but it also feels raw and basic. In design philosophy it's more akin to a BSA Gold Star than a modern, civilised Powered Two Wheeler, and it really is great fun to charge around your local back lanes. But its too small, both physically and in engine capacity, to be used for anything more and you really wouldn't want to be setting out for distance horizons on it. It will give you the most thrilling ride down to the local chip shop and back, but apart from that I can't think of a single practical use for it.

I can see why there's such a buzz around this type of bike, but it really is not my can of oysters. It's lots of fun, sure, but the fun is compulsory and uncompromising and I've spent too much time hanging on for dear life to enjoy the ride. Buy one if you dare, you won't have a dull life with it. But buy it as a second, or third, bike. The Duke really is a toy you'll enjoy getting out of the garage for the odd quick blast round the block before bringing out a proper bike for going places.

But for performance I do have to rate this bike. It's a gut wrenching adrenaline fuelled bolide that encourages you to live on the edge. It's as mad as a very mad thing, and in terms of thrills per cc it's almost off the scale. Brilliant. But for comfort, forget it. The seat is as comfortable as a plank edge ways up. But if you're sitting down on this bike you're missing the point. This bike is not for softies who wish to rest their arse.

Street cred is another matter. People in the know will swoon as you pass, and gaze in awe at your two wheeled prowess. Those not in the know will think you're slightly mad and riding a slightly mad bike. Both will be correct. And reliability? I think its a little too early to tell yet as in my experience most of these bikes get crashed long before anything has a chance to wear out. Buy one and prove me wrong.

Dr.Rod.