I think Stu was right when he said some people have too much time on their hands, with my Sport I didn't want one drop of oil showing anywhere after a ride unlike old Brit bikes of my youth. I found out that with the standard catch bottle some oil mist could escape from the vent hole and cover the frame and even though it was mainly out of sight it annoyed me, so a modification was on the cards. As you can see where the vent hole was a small length of tube was araldited over it and a little cotton wool placed inside to act as a breather that doesn't leak . Yes I know it's very sad and anal but I'm not bothered because I have tons of time on my hands.