superbyke rmr 125 modification help please

Hi nee to this site in need of a little bit of help if possible please I have a superbyke rmr 125 I have a yoshimura exhaust end can at the moment and it seemsto give it abit more power but im looking to see if I can get more owt of it anybody no what size carb is on thn so I could but a bigger 1 on or what jets to put in . Or is there any thing else I can do just to giv it that bit more its sitting at 70 on flat but would like to see what u can realy get owt of these little bike