Just changed the oil and filter on my FZ6 on a 07 plate but not sure if I put in too much oil , cant find my book for capacity but seem to remember that you check it on dipstick after running engine , did this but im slightly over the mark on dipstick .
It's 2.5 litres if you just change the oil, 2.8 litres if you change the filter too.
If I were you I'd let the bike cool off completely, then run it on idle for a few minutes until it's up to operating temperature and the oil has circulated. Switch off and leave it for five minutes to let it drain down, then check the level again.
If it's still over the mark, you're probably best off buying a cheap turkey baster for a few quid and using that to suck some oil out, although I've never tried that myself