No "jibber-jabber"? I don't know if we can do that...
Find a compression calculator and figure out what you want, do a search here to see what's reasonable for c.r.
Here's just one of many.
So far, with the 75cc heads, gasket and other info you provided, assuming 6 cc valve cuts on flat tops, you're at about 9.74:1, with 64cc heads you'll be at 10.48. This considering the piston is .025 in the hole.