are the 70cc & 80cc the same?
I have a 70CC engine with 8mm headstuds & I know the 80cc uses 6mm headstuds & a thinner headgasket but is the cylinder really larger?
if it is can I put one on my 70cc engine?

also does anyone have 70 or 80cc rings & cylinder as a set?
I had to ride mine in heavy rain a few weeks back & today when I pulled the head off to put in the thinner gasket I found some small gouges near the top of the cylinder
its running well but Id like to have it rite
take care


MB Builder Extraordinaire
Jul 21, 2008
coventry, RI
the "80cc" chinese bike motor is a fantasy....they do not exist. i dont trust any seller so blatantly dishonest about displacement. makes me wonder what else they're not saying truthfully.
they're all closer to 67-point-something cc's. Dax motors use the 8mm headbolts, on 70cc as well as 48cc.

pretty much all others that i know of use 6mm headbolts, 48cc or 70cc

EDIT: the last few motors i've gotten from different factories have been 8mm
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