i have a mild port (clean up ) and they work perfect. just call them up and talk to them.the guy i talked to was jeff , he knows his shit , he told me they are perfect for stock motors , he said if you have alot of port work ,stroker , mods like that go to 33mm -35mm , call them and talk to them , they stand behind their carbs.
my banshee has never ran so good. 200 bucks you cant go wrong ,