I'm going to assume you mean for a banshee...
First bore is .020, then .010 additional after that. So... .030, .040...and so on.
Once you get to .080, that's your last safe bore in my opinion.
They sell a .090 and .100 kit...but the walls are so thin, it's a time bomb...tick tick tick.
First off, check your numbers. Wiseco does not make a .0030 kit of oversized pistons that I know of (US Measurements).
The Metric increments are by .25 mm
64.00 is stock, 64.50 (.020), 64.75 (.030), and so on...