Always give year, make, engine size and model # when asking questions. We need all of that info to give an informed answer.
Sometimes the year can make a difference.
Unleaded
Premium or regular will be fine in that model.
http://www.kawasaki.com/DefaultFrame.aspx?strContentUrl=/SITE/VIVEHICLEINFORMATION/VICHOOSEVEHICLE.ASP
Go to - your bike - Specifications