Last week i was having a blast on my bike, it felt great. But on Sunday a lot of whitish smoke was coming out of the exhaust. On the previous day i had closed the gas and burnt all the gas that was in the carb before storing it. So i tought that it was just that the bike was cold or something. I went riding for a while and everything was ok at that point. Well today i poured new gas in it and a lot opf white smoke was coming out odf the exhaust and from a hose that is on top of the left side of the case, in front of the spark plug. I warmed the bike well and on the test ride the bike had no bottom or middle power, and when the revs were high the power kicked in hard... but nowhere near the usual power. The motor sounded pretty strange. Does anyone know what might this be? I tought that it could be the rings. A friend of mine says that maybe the powervalves are full of carbon buildup. Why would the bike get messed up so suddenly? BTW it is an 06 KX250. Thanks guys.