I'm assuming you mean the dreaded 'BMW buffeting' effect? If so, your best bet might be to have a look at the UKGSer or the ADVrider sites as there's been much mentioned about this problem. You might need to sift through some dross before you find anything of substance though ;-)
I'm 6'2" and have got a 1150GS and have had a lot of problems with 'buffeting', so much so that it feels like getting your head kicked in once you get the speed up. I've tried a replacement screen (higher & wider) with and without Tobinators (which give the screen a bit more adjustment) without much success, and have now gone back to the stock screen which isn't that high..
I was convinced (and still am) that Tobinators are the most expensive 4 bits of metal and some screws you will ever buy, however I've persisted with them and today after much tweaking, I finally seem to have got the bloody buffeting reduced to a bearable minimum with the screen set about as far back as it can go. This is actually a compromise though, as you need the visor down all the time otherwise the wind and bumble bees will hit you right in the eyes and you really don't want that.
Last edited by MikeS; 13 Aug 2006 at 23:29.