What's up guys , my Drz just rolled of 36,000 miles . I was riding the other day and the motor had took a shit . Got home tore it apart to find that a piece of the valve guide in the head had broke off , went down in the cylinder and caused carnage to the piston and the head . I got a new head and big bore kit from a friend. Installed it go to start it , it started for 5 sec and then locked up on me. I took the valve cover off and noticed that the intake camshaft had spun on the cam gear. Weird! Had another set of cams I threw in . Timed it correctly , put it back together and started it . Same thing ran for a few sec and locked up. Took the valve cover off , cams out , and the intake cam was all scored up and the journal where the cam rides on the head was all scratched and rough. I have no idea what caused this . And on top of that there was coolant in my oil . Bad head gasket ?!?! Still doesn't explain why cam spun on the gear , and then second set of cams just ate the journal and ruined the head . Any input ?