Actually 34mm is about the perfect size, the pj carb can be a pain to jet though. Take out your reed spacers, they cost you mid hp and torque. Try 195 main jet, eej needle in center position, 45 pilot jet, 1.5 turns out on air screw. That will probably get you close. You may need to adjust the needle and main based on your riding climate temps. Also may need to go down a few pilot jet sizes. This should put you in a safe starting range though.