I have a Yamaha 2hp motor with a plastic prop that I thought had a kinda funny shape as the blades were completely flat on the trailing edge. I have since found out that this is called a cleaver prop and that they are used in racing and run best when only partially submerged. I did raise the little motor up and the boat ran noticeably faster when the prop came partly out of the water. Why in the heck would someone put this type of prop on a little kicker? Is this shape easier to manufacture or what. This may seem like a dumb question but I haven't seen any other little kickers with this shape of prop. I'm sure not going to do any racing with a 2hp motor, but I guess I can pretend.