Long story short, my engine was overheated. I replaced the top end and gaskets, and now I'm trying to adjust my valves. The exhaust cam is fine, but the intake cam won't spin when I torque down the cam cap. The clearances are actually loose right now with the shims I have in, so there's no contact there. The journals appear to be fine, no obstructions or anything. I was using a hot cams intake cam for a while, including when it overheated. Now I'm trying to use my stock cam again. If I hand tighten the cap bolts and snug them a little bit with a ratchet, it will spin fairly easily, but any tighter and it won't turn. Any ideas? If someone could get back to me today, that would be great since I'm trying to leave for a trip tomorrow morning. EDIT: This is a 2006 YFZ450.