Ok so my friend has a 2005 kx250f. He went riding this weekend and somehow the drain bolt came loose while riding. He does not know how long the bike was ridden without oil in it but it did not seize or anything. The problem. It is now stuck in first gear. My question... I am going to pull the valve cover off and see if theres any bluing on the cams, if there is I will most likely just tear the whole motor down, BUT if there is no bluing I have to assume it wasnt ridden without oil for long so then what should I do. should I try to just fill it with oil and roll it around and see if the gears free up?