ATC70 blue smoke

[peerieivan]

Hi, i've got an 85 atc70 that seems to blue smoke a bit, i'm asuming it's burning oil a bit because of worn piston rings but just wondered if thats the normal complaint or if it's something else, i hav'nt had the bike to long so not sure how much oil it's getting through, it starts and runs OK but seems to foul a plug within about a couple of hours and when i take the plug out it's well black (thinkin it's the oil fouling the plug) Any advice would be most welcome, thanks guys

[Mr_RPM]

yep, sounds like bad rings. time for a new piston the next size up and a fresh bore. check everything else out while you have it apart, like the valve guide seals.
you MIGHT be able to just replace the piston rinds and just hone the cylinder but thats not a 100% fix.