Cleaning brass

["atrav" <atrav@copper.net>]

    It's gotten to the point where I have enough motorcycle jets and other 
brass carburetor bits
that when tuning sometimes I can reuse old stuff. But, the old brass jets are 
real cruddy, is there
a good brass soaking type of cleaner (phosphoric acid?) that would clean these 
jets well, but not
damage the orifice precision?
TIA,
-Aron-