I picked up this quad for barely anything recently. Cleaned the carb and started it up and it pours white smoke at idle and when moving. I pulled the head and jug off and noticed that the lower oil ring gap was located over top of a piston hole. I'm guessing this is what caused the oil to get in.

Can I put these same rings back in and just move that lower ring or do I need new rings and a hone ?

 

if you dont wanna take it apart again bore it out new piston and rings and its good for years to come. just a set of rings and a hone would do the trick for a short period of time.

 

I agree that it would be worth your time to put in a new piston,rings, and possibly valves. Check your intake valve to see how worn it is. My intake valve was shot and my exhaust was ok but replaced both of them anyway.
I recently rebuilt my 230S with a Wiseco piston/rings and a set of Vesrah valves. It runs incredible! Alot of fun!
The rebuild cost me $200.00 including all of the machine work.
My only problem now is the old clutch won't handle the new power!!
I'm sure if you wanted to take the parts into your local cycle shop they would be happy to tell you if you could salvage your old parts and put it back together or if an overhaul would be more beneficial.
Good Luck! Don't be afraid to ask any questions there is certainly alot of knowledge to be had on this forum.