kx 250 2000 stopped working! please help
 

can any body help me please i got a kx 250 2000 and it was bogging so i tuck it to a garage and he checked it out and said it was down on power and was fouling the plug. after some checks he said the stator needed replacing so i replaced it and the bike was fine for about 30 mins then it started bogging at high revs and fouled the plug again and now its not starting i checked the plug and its abit oily after cleaning it its not starting very well. what should i be checking could it be the carb set up or the reeds etc? the man i got it of told me he up jetted it but he couldnt remeber what size jets was in it could this be the problem. thanks