engine making a ticking or hammering noise??..read this

I have a 66cc 2 stroke standard motorbike kit..(chinagirl). I have about 300 miles on it so far. its been running great with no major issues,gets me to work everyday..about a 24 mile round trip. ive been hearing a hammering noise same as my engine rpm when it warms up at operating temp. I read all the posts,from wrist pin bearings to crank seals to pistons. I ran across one the other day and decided to try the fix. came to find out my piston was hitting the head gasket!!!. took the head off and flipped the gasket around and turned it 180 degrees.. problem fixed! she purrs like a kitten. sweet! id like to thank this informative forum

Did you try tightening the head bolts down first? Mine starts making this after a few hundred miles and bringing the tension back up on the head bolts always fixes it.

At first i thought that my head bolts were loose so I did tighten them. My motor felt a bit tighter but still made the noise. It still makes a sound as if my piston is slapping my jug at high rpm again. The motor is running great though. I'm reaching a top speed of 34-38 mph. I did some mild porting and drilled a few holes in my stock exhaust