e220 coupe, Kawasaki ZX10R and a chugging H/D 883 Sportster.
Try cleaning your glass with white spirit which will remove the crud that detergent doesn't and see if that helps. Even if you think your glass is clean you will be surprised at the amount of dirt that is transferred onto a piece of kitchen towel.
I had similar issues but was more or less convinced it was the wipers on the glass that was generating the noise rather than linkages. I tries cleaning the glass with everything I could think of. In the end I used an abrasive glass polish from Amazon and that fixed it.