I've tried 4",6",8" and 4" 6" windvest with not luck stopping it. I use a fullface helmet and that may add to the buffeting. I used a 12" shield and that did work. I have a street glide and like the lower shield. I also installed the air baffle under my batwing and side air deflectors none worked we'll for me. I think it comes down to a good helmet and ear plugs.