To be fair, this is Kawasaki we're talking about. Only company I know that's nuts enough to put out a 250cc inline 4 screamer in the ZX25R. Then also produce the H2 which has a supercharger with holes cut into it so that you can hear the chirping of the impeller blade tips exceeding the speed of sound and generating a small sonic boom.

Don't know of another large motorcycle company that's willing to try wonderfully silly things like this.

I'm only speaking from my own experience but my Suzuki VStrom has about a 5.5 Gallon tank and the Kawasaki hubrid has a 3.7 gallon tank and they both get about the same mileage so I think it still gets a better MPG.