Last year I had the same problem. It doesn't want to idle and then it gets stubborn and doesn't want to start. Its a 2012 model and has close to 500 hours. I took it to the dealer last year and the injectors were cleaned. It ran decent for six months. I've put in injection cleaner and installed new spark plugs this go around.. No change. Do you think it could be the throttle body? Once I get it started I can fly down the road at high speed without a miss. When I slow down it won't idle and again stalls. Sometimes it takes numerous cranks of the starter to get it going and then I have to keep on the gas to start out and I usually grind the gears. I might have to visit the dealer. Thanks for listening.

 

Check for water in fuel.

Alan

 

I had same problem with mine(2011).throttle body cleaning help but not that Much.finaly fix IT by replacing Drive belt!too much used on IT,résult :engine is stock with the convertor.and if belt is replace,use the original parts and make to have IT Shim by Kawasaki mecanik.very important.