I had an issue like that with my 2013. If the engine was hot, like 200+ degrees, the bike would not want to start. It was stupid having to rev my bike while pushing the starter when at the gas station or in the canyons. My bike is a cali model so I thought it might be the extra emissions stuff we have. Bypassed all that and still had the problem. Next I tried getting my ecu replaced by my local dealer, but they wanted way too much money. There was never an official recall, but some people had luck getting Kawasaki to replace the ecu for free under warranty, but I bought my bike used so I was SOL. I ended up buying a used cali model ecu on ebay, swapped it out and now the bike starts the first time, every time. If you pull your ecu the part number you probably have is 21175-0812 112100-9872. You want 21175-0812 112100-9874.
Edit: Forgot to mention I had the low idle, slow start when the bike was "cold" like you have. The ecu swap fixed that too.
Last edited by jel1990; 11-03-2016 at 09:09 PM.
Reason: Added info