Your piston rings are actually a set of rings not just one. If the oil ring goes bad you'll still have compression but it'll burn oil like no tomorrow. My 2000 gsr did the same thing around 110k. It'll smoke a crap load in the top end because of the extra pressure the motor gets put in. I replaced my valve seals around 80k. When that was problematic it would only smoke when the car was first started. Usually the oil will leak down the seals when it's not running and when you start the car it will burn that collected oil. Yes it will burn oil the whole time you're driving but not usually not enough to see alot of smoke. With the amount of oil you're burning with no gasket leaks is definately your rings.