no restrictor in that mate im afraid,the best way to get some more poke out of it is to fit a 120cc big bore kit and a gear up kit,you will need to re jet the carb or fit a bigger one for better performance.light weight rollers will only improve the bottom end and if you go too light it will make you lose top end speed.doppler pipes are good so no worries there.good luck with it
adam bike doctor(of milton keynes motorcycle centre)
November 2010