Did you leave the gas petcock on the "ON" position when you parked it? Sometimes if you have a sticky float in the carb and a clogged overflow tube, the gas will just keep flowing and find its way into the crankcase.
since you have it apart, do a ring end gap measurement, and see what that it comes to. Go from there. Good luck,
------ jon
THE 80's RAGE! Currently owns:
81, 85 Yamaha Tri Moto 125
83 Yamaha Tri Moto 200 x2
82,83 Yamaha Tri Moto 175 project
85 Yamaha Tri Z 250
84 Kawasaki Tecate 250
84 Honda ATC 70
85 Honda ATC 350X
84 Honda ATC 250R
(2) 84 Honda ATC 200x
82, 83 Honda ATC 185s
81 ATC 200
Lots of other parts and bikes