I don't have any experience with that bike, but there are similar things used on some mopeds to keep noise and power down. They do that very efficiently, making most kinds of tuning worthless unless the exhaust is replaced first... I can't tell you what to do with your exhaust or what the result from gutting will be, but all that junk put inside a expansion chamber would hardly make it work any better. The chamber is supposed to work by reflecting pressurewaves back and forth, plates and tubes inside it will not do it any good... ;)