here is the answer you first asked, where can you get different jets? Bing, just google bing and you will find them. they have all kinds of different sizes available and talk to one of the tech guys they will point you in the right direction to start. also while your ordering your jets get the bing carb manual they have, lots of info and helps set up them carbs better.
some of them KN's can be helped with a little alum. wrapped on the outer side of the filter so it can breath from the inside but you are losing the free breathing you get from them pods. another thing you could try is put a washer in front of where your pipes meet the mufflers (in your case glass packs) that will add a little back pressure in your exhaust so your scoot doesnt fall on it face at the upper end.
