Just wanted to add my 2 cents to this older thread about improving air flow to the airbox
I have a 2011 fe 570 and is a much loved bike..
What I do for better air flow is simply don’t lock in the middle lugs on the seat.. by installing the seat in the front lugs with the seat tilted on a angle then locating the rear pin to lock it in place the centre locators will be above the pins.. then I sit on the seat to slightly force the lugs to come to the sides of the pins this will bulge the seat right above and round the air filter giving greater air flow to the air box without having to cut holes to top of seat or shrouds.. if it’s a wet day I simply just install the seat with all locations in place preventing any water getting sucked in the air cleaner..
Hope this helps someone
Best regards