I did a trackday with the ram air ducts as standard in fully working order. On part throttle mid corner and at certain revs the bike was jerky and ran rough. Fine on full throttle. Second trackday, modified ducts (with the ducts closed the whole time) the throttle was smoother without the rough sounding running gone. No noticeable difference in performance that I could detect. I would like the smoothness and improved throttle response so i will do the mod correctly now I know what I'm doing