Mass Smoke out

A friends 450 Foreman started smoking all of a sudden. We couldn't fix it for nothing. Took it to the shop and the rings were GONE. A few new rings and the bike quit cold turkey..Possible?

i have the same bike as you and i had the same problem 4 different times including it happend last weeked too, all you need to do is order new gaskets and rings and she should be fine

Well, mine has done that twice now. Both times we had it bored and a new piston, rings, etc.

Thank you everyone, rings and gaskets did it

Mines smoking too, BAD, so I pulled the head and jug, the valve area looks like ?hit greasy, greasy, greasy, the plug is greasy, the piston top is almost all silver except for a small soot spot and the cylinder wall looks ok.
I think they used a cheater bar to put the head nuts on, man they were tight.

Tomorrow is measure the jug and take the head apart and measure day.
Rings are not stuck or broke

Any suggestions? Also where is the best place to get parts?
Thanks,

Valves are carboned up, piston measures 3.410, cylinder measures 3.416, top ring gap is .035, middle is .047 and oil rings are .08 the best I can tell, also piston pin has wear marks. I'm going to order a new .75mm O/S piston & rings, gaskets, and valve seals, de-glase the cylinder wall and hope for the best.