I think this forum is based in the US, moreover naked FZ6s are not avaliable from factory in there, that makes fz6 nakeds (all colors, white, grey, orange, yellow etc.) rare in the forum against fazers...
Thanks guys for you solutions. I keep them in my mind. ;) I am not gonna use engine oil. :D
What do you think about sound? Is it normal after adjusment? It looks like a differential sound in cars...