Motorcycle Repair: 2001 CR 125R, original chain, sprokets

Question
Just bought the bike this weekend. The bike has very low hours it still has the original chain, sprokets, and brakes. It was riden very little and has sat for the last couple of years. The owner started it several times a year and winterized it yearly. The problem, the bike will not hold a good idle. I removed the carb and cleaned thoroughly everything looked good. I adjusted the idle screw but the bike will hardly hold an idle and I am almost out of adjustment. We went out for a ride. The bike sounds like it is loading up on the bottom end, it has a bogging sound, but is very strong at the middle and on the top. It ran good  otherwise. The bike consumed twice the amount of gas as the other bikes. The compression is 90 psi. I removed the top end and everthing seems to be in order. The exhaust valve was operating freely, the piston and ring looked goood. The air filter looks good, clean, and not over oiled. I removed the packing from the silencer and even that seemed fine. What am I missing? Why won't the bike idle properely and why is the bottom end so bogey and loaded? Please help. Thank You  

Answer
correct me if i am wrong,isnt the choke and the idle work off from the same circuit in those models.what i mean is i think that you turn the choke lever on the carb to raise or lower the idle.I am 90 percent sure,if i am right the carb is still dirty and needs to be dissassembled and cleaned.