Compression issue

My guess is safety wire. In any case getting the debris out is going to be difficult without pilling the head. There is very little room to get it out otherwise, especially with a camera in there as a guide. What does the top of the piston and cylinder wall look like?

Hi Walt.  Top of piston and walls look normal compared to other cylinders.   

Thx!

I think Walt is right.  Get this to someone who can take that head off and inspect it all.  No doubt it came from the intake side, that is suction.  The exhaust would not eat anything like this.  Check your air filter and intake system.  If someone had the carburetors off perhaps something got left inside the carb body on assembly.  Just guesses until you take it all apart.  I would also check the cylinder that intake manifold to be sure nothing got to the other piston shared by it. 

Cheers

What RW said. He's spot on and he knows better than anyone else.