question about swapping heads

[Lecanardwpg]

I have 74 ct 70 thats smoking bad, I can pickup a lifan 72cc engine E22 head for 100 and would like to know if i could just swap the heads

thanks

[mjfrank]

Are you just buying the head, or the whole engine?

The short answer is, maybe? The dome shape and the rod length varied during the 70 production. There are two different dome shapes made in replacement heads (old and new), but I don't know what shape the Lifan you are getting has. You can get a little better idea here:
COMPONENT ENGINE PARTS_ONLY

Basically, you could try to mount the head, and then slowly turn the engine over by hand to see if the piston contacts the head. Don't force it at all, if you have the spark plug out, you should have very little resistance. If it does contact, then you'll need to swap the piston out too. The newer dome heads need a piston that is slightly undercut, to clear the edges of the combustion chamber.

--Mike

[bjatwood]

If you put a Lifan head on it you will need to change out the piston also. And if it's smoking a new piston and rings would be a good idea. DrATV has a "freshen up kit" for CT-70's that include a new head and piston for 109.99 dollars.
Good Luck
QUICK_FIX_SPECIAL MOST_OLDER_70CC'S

[Lecanardwpg]

yep its $100 for the whole engine, I Think its a deal as i live in canada and the shipping and duty would be $150 ish