As a kid a mate of mine had a kart with a Villiers 9E engine in it (2-stroke 197cc single) that went better than the one in the film. I used to love driving it and it had the capacity to scare the crap out of me even in 2nd gear. A big engine doesn't make for a better kart. How much of that GSX1100R's engine potential are they actually using on a kart track? 20% maybe.