Maybe I'm wierd, but I like jet skis most of all for their efficiency, compact size, and maneuverability. I'm not a huge fan of racing or wave jumping, and figure I could live with less speed if it meant better efficiency, lower noise, and had other advantages.
Well in my neck of the woods, many lakes have a horsepower limit of 10hp. They're small or at least tight enough that that's not a big deal at all. Jet skis would be perfect for navigating the small rivers and lakes at a reasonable speed. But they don't come in 10hp.
I was thinking of building something on the technological level of a go-cart that was basically configured like a jet ski, but was slightly smaller (for transportation) and had a 10hp powerplant.
Maybe I'm missing a lot, but in my engineering courses I learned that frictional force in water is a square function of velocity, and that power required is therefore a cubic funcion. That means that if an 85hp Sea Doo jet ski can pull 65mph, and the function of power vs velocity is cubic, with a minimum at zero, the same craft with a 10hp engine could pull 30mph. (Power = 0.00039 * Velocity^3
Make any sense? 30mph would be more than enough for my uses on inland lakes and creeks.
I see a jet ski on E-bay that has everything but the engine intact. Can't afford it now, but suppose a 10hp engine could be fitted to the existing systems?
