Knocking at higher RPMs???

the piston gets too much clearance after the cylinder wears down but your ride is new so that is not the problem
 
too much chain slack can cause the chain to hit the crankcase at high speed
 
Watching on YouTube and the guy said that the arrow on the top of the piston needs to be pointing towards the exhaust port. Is this true? I have never moved mine, yet it is pointing towards the carb port?
 
Well these are china engines so go figure. They may have stamped it on the wrong side. Pull the cylinder & make
sure the ring end gaps are toward the intake side. The back of the rings always face exhaust. I don't think that's
the problem, but to be sure check. I would have thought you would have already hung a ring by now.

Fly
 
the top ring end gap was facing the left, and the bottom ring was facing the right... Should they be aligned with each other?
 
No there staggered, but should be more facing the carb an intake side the cylinder.

Fly
 
Ok, I got that figured out. They must've stamped the arrow facing the wrong way then. Still not sure what's causing the knocking sound though.
 
exhaust can pop out from the cylinder head mating surface if its not perfect.
all these engines have warped planes there. You have to plane them flat (both cylinder head and cylinder top) with sandpaper on glass.
 
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