Hi, my 2002 yanaha yz426 has a problem.. Wondering if you guys could help. I couldnt get it to start, then today, I got my bike to crank. Had to put new cylinder and rings on it. The old one was scarred up on one side and the plating was kinda... Rubbed off, i guess on the bottom of the cylinder. Anyway, it runs perfect for 10-30 seconds, then locks up. I turn the crank opposite way, unlock it, and it cranks right back up and locks again. I can always unlock it. no "ku klunk!" sound when it locks up. its real quit. as if you just hit a mute button. no smoke or anything. also has metal shavings in oil.. is this my crank bearings? bent rod? bent crank??