Hey guys....i got my motor back from kor a few weeks ago and broke it in did everything right and its been doing great. Well every couple rides i make sure all my head bolts and everything is still tight.....and last night i checked before i put it up and one of the head bolts wont tighten up...i dont know what happened because it was tight then checked it and its like the stud on the cylinder is jusy spinning on the inside. Any help on how to fix this would be greatly appreciated. Thanks