Hi, i am having a time trying to figure out this gargling sound out the exhaust is. Its fine at WOT but around a quarter to half its a weird sound out the exhaust like its fluttering until i open it up. i have cleaned the carbs and adjusted the float height and mixture screws, also the Oring's in the seats. All three plugs are tan color. I live in Indiana so there is hardly any snow to test it out and when it does snow i would like to be prepared. I've read on here about reed spacers? and shims for the needles. I'm not sure what im looking for so any help would be awesome.