re: 60 MPH...achieveable? Who cares?!? Let blueprint an engine!
As this was done fifty years ago with 50cc moped engines without chambers, I wonder what we are all waiting for? 60mph with 66cc in 2010.
Its an interesting endeavour just the same, to make chinese junk fly/fry.
Heat will kill it in the end.
Unless you go with methanol or water cooling.
Then 100mph from 66cc might be more impressive.