When you get to the pop off preasure to between 12 and 15psi, reassemble and run the engine let it get hot run it for about 2 min before adjusting the needles, set the high needle first turn the needle in untill you reach max rpm and then back it off 50 to 100 rpm. Then adjust the low end needle bring the throttle up to about 1800 to 1900 rpm to make your adjustments turn the needle in untill the transition from high to low stumbles(almost dies or does) then back off the needle untill you have no stumble. If it still burbles make sure the carb is clean if so do the lever adjustment and retune as above and repeat untill the engine runs like you want.