When I was trying to decide where I wanted my shield, I'd go down the road and stand up and let the wind hit my face. Then I'd lower toward the seat and when the wind no longer hit my helmet I mentally registared the relationship between my face and the top of the shield. So when I sat down I adjusted the windshield so it was in that same position. Now when I ride down the road at highway speed, I can double up my fist and place it on top of my helmet and and feel the wind going over the top of my fist. Works for me. Enjoy your Street Shield. Nice windshield.