polini 64cc kit
78 jet (using kit straight outta the box)
I sanded the mating surfaces of the cylinder and head to get rid of the high points, which raised my compression by less than 10psi, and my jet size dropped to a 68. It's amazing how warped they were when I got them.
Also, the bing 14 doesn't cover the full range from idle to WOT very well.you either have to jet for top speed (which will be way too rich at idle, and you'll have to shut the bike off at lights and such) or for daily in-city use, which will be too lean at WOT. I jet for daily use, rather than racing speeds, and can cruise at 40 and top out at 45 before overheating.