The idle speed is to low it should be 1.5 Rpm the idle jets do just whot there colled only control the idle .Its the main jets that give you your throtle . when setting up your carbs you plug your vacume gauges in to the inlet rubbers each rubber has a plug on it . you have the revs up to 4000 revs and the gauges should all be equeal and if not you will see four screws on top of the carbs adjust to equeal