my irvine 46 isnt running propperly and wen i throttle up it goes slower and mumbles and sometimes it doesent im gonna strip down the engine is that wise i no what im doing there might be a bit of rubbish in there ore a blockage ive tried every click of tunine and it just doesent help?

pleASE HELP ME ITS GETTING LATE AND IM GOING FLYING IN THE MORNING HELP HELP!