hey man sounds like ur main circuit in the carb is not engaging and only the idle circuit is, does that carb come with a small brass disk that is held in by the main jet?? (between the main and the diffuser) many of the dellortos do, take it off if, and throw it in the trash, then try again, and see if it still is having the problem.
yo quickref, that info is just wrong, i got a 132 main on a shreding polini, and no air leaks. some motors need it.
brandon is right tho many metras out here r running in the 80's.