Hello. I recently purchased a 2002 DS650 not running. Just heard it crank over. They said it just had the head redone. I'm guessing valves but who knows. They basically said they can't get it to run so done with it. So I bring it home and get it running, (new battery, cam chain tensioner) . Sounds good idling but after running for about a minute it seems to seize, Engine gets tight and starter won't crank it over. Let it cool. Starts right up again. Same thing. I took off the cam cover, looks to be good at top dead center, cams pretty close to marks. What I discovered is exhaust valve clearance at .004 and .012. Intake at .015 and .018. Intake cam seems to have a little wear around tip area, like a little chrome pealing effect. I then remove cams and discover the exhaust cam has absolutely ZERO oil on the inner cam journal. I'm thinking this is my slight squeal and lock up?? I'm looking at this thing and can't figure out how the cam journals get lubed. I see the oil groove but what feeds it?? The other journals had oil. I realize I need to shim the valves but I'm a little confused and concerned about the dry cam journal.