I think that one of my crank seals was leaking, causing it to run very lean. I will be replacing all seals and gaskets and unfortunately I have to split the cases to change the crank seals, but I planned on splitting them any way to check everything out and replace the crank bearings at least. I also just read that Kawasaki say's to change the crank seals every two years or as needed, I'm pretty sure they haven't been changed in a few more years than that!
I have put over 100 hrs on this bike since I bought it in Sep of '08, I don't know how many hours it had on it when I got it, so I guess it was time for a rebuild. I was down in OR at the dunes when it died, we were at sea level to 150', I had the jetting dialed in for about 1000', not sure if that had a lot to do with it.