Simplicity is always beautiful. this is the most beautiful and simple motorbike design I've seen in a long time.
Not necessarily easy to implement though - a simple final result often implies powerful tools.
For this particular bike they're talking about 160 HP for 140 kg. Scary. I'm going to stick to old faithful for the time being! (the one you see on this last picture is not mine, I have the 1993 model).
update: Marc is afraid about one burning one's ass on this thing. I should have mentioned that they're supposed to add some kind of seat and body to this thing ;-)