Don't know much (anything) about the way Yamaha does this, yet friend
of mine has a sea-doo 14', 85HP 'boat'. Since it is a jet drive (like
wave runners) they use *tons* of fuel to stay in the sweet spot (above
4500 RPM). Since there is no torque, you really spin the impeller.

May want to keep this in mind for weekend fuel consumption or the
ability to pull a 210 lb skiier out of the water on one ski.

-jjj

I didn't realize that these were gas guzzlers. I was under the impression
that this boat got about 3.5 - 4 mpg.

"Jay" wrote in message
m...
Don't know much (anything) about the way Yamaha does this, yet friend
of mine has a sea-doo 14', 85HP 'boat'. Since it is a jet drive (like
wave runners) they use *tons* of fuel to stay in the sweet spot (above
4500 RPM). Since there is no torque, you really spin the impeller.

May want to keep this in mind for weekend fuel consumption or the
ability to pull a 210 lb skiier out of the water on one ski.

-jjj

Maybe Yamaha does it differently, dunno. I would be wary of the
'torque' of an impeller versus a prop. For skiing, wake boarding,
etc, you ned torque. AGAIN (So no one jumps me) I have experience
with a 14' Sea-Doo / 85 HP two stroke. It went staight fast. If you
threw it into a hard turn, it took thirty seconds to start building
speed.

Anyway, I have a 19' Chaparral w/a v6 / 190 that runs 55 MPH. I had
the seadoo by about 3 MPH straigh and a full lake if they had to turn
the Sea-doo.

The benefit of the Sea-Doo was light (1400 lbs), no 'transmission',
and a two stroke. BUT it likes to cruise @ 4500 RPM. My 4 stroke
cruises at 2900 RPM.

Good luck, seams like you are doing your due dilligence.

-jjj