At 6'4" on a 750, my head was just enough above the windscreen (chin level) to make it feel like my helmeted head was in a paint shaker. I started by cutting about three inches from the top, and then another three, and then another three after that. Each time I cut, i finished the top edge so it was actually smoother than the factory edges. After each cut, I would ride it and see how it felt. Now the top edge is about 1 1/2 inches above the vertical strut screw holes. It does a good job of moving the air around me, and the shielded handlebars are PRICELESS on the 37 degree mornings we have had already this fall. It is still tall enough that I can duck down behind it (my eyes just above) on the interstate and the only thing that freezes are my ankles.