Jerry... Ive done three motors since the Rossi's and dont remember exactly as I didnt write down what all I did to them, and dont want to take them apart to get exact numbers....but heres what I do remember.
The exhaust got moved up to around 176 or 178 degrees, not sure which...( I also cut a .020 "top hat" configuration into 1/3 of the top of the exhaust port, obviously had to match the case to that.
After raising the exhaust, I had to hog the **** out of the case exhaust outlet area... it was way to small and choking in that area. removed a LOT of material from inside that exhaust spigot.
Matched the sleeve tranfer tops to the top of the case passages without moving the timing.... it was horibble. Almost .035 thous. hanging down below the case passage.
cut a little here and there on the sleeve at the intake window and tranfer window to help things move along with the proper amount of "swirl"
Turbo cut the crank, cleaned up the opening side of the crank window, about 0.012 thous worth.
clearanced the big end of the rod.
got the piston to actually "fit" the sleeve, also releived where the sleeve sits on top of the case with a little deburring tool.
Got the head clearance down to 0.007 with a 0.004 headshim installed.
.18cc bubble volume with 1/3 squish band at 1.5 degree angle. Its got a couple more cuts in the head, but nothing we havent seen before. I modified a stock CMB TT head button to make all of this happen.
Using the stock water jacket for now, will see how she heats up or deosnt and go from there. Im not big on air cooling a motor as its to easy to overheat one, but will if I have to.
Thats about all I can remember... ~James
PS, oh yeah... I got Rod G. to do his magic on one of his carbs for me and make an adapter to the rossi.