Just installed the 13 inch Clear Cee Bailey's windshield. It's actually 13 1/2 inches from the top of the rubber fairing gasket. I'm 5-8 using a stock seat. The shield does a great job of keeping the air off my face and over my head. I've tried it with an open face helmet without any issues. Wish I could go to the 15 inch but it would appear the top edge would be right in my vision. Have tried the 11 inch and the wind and buffeting would hit the top of the helmet.