It has not been revealed yet by Kawasaki though somebody else made a good effort on making one. Simply he put a stock Sea Doo (why on earth you want to put a Sea Doo engine in there in the first place?) three cylinder engine into the SX-R engine compartment. It looked quite good and there were people who found it an interesting project. On the other hand I do believe that somebody out there have already tried to fit a four-stroke Kawasaki 15F motor in there. That would be a challenge or even better if you remove one or two cylinders and add a turbo
