Thanks for the replies guys. I was up til 3AM last night dicking with this. My list of what I've done and think I need to do seem neverending, so be prepared. I wrote everything down so I wouldn't lose track of what I've done...
The metal noise I'm searching for only occurs when there is compression. If you remove the spark plug, no sound at all. Remove the head, again, quiet. With compression, ping, ping, ping, ping, ping.... pretty freakin' loud. Like I can't hear the exhaust note well because all I hear is metal pinging.
I have TWO kickstart korado cdi motors with the needle bearing cranks. Both are super new with like 45 milea and 200 miles respectively. Both quiet and perfect with the stock setup.
My Athena kit has the reeds on both sides.
I will buy the carbon reeds today.
I want a 70cc head for this thing!
Anyway, here's what I've done so far:
I installed two base gaskets thinking the piston may be striking the head. Nope. Went back to the athena gasket and stayed...
Realized the head was on upside down. I never noticed the arrow on the head previously, so I flipped it and the gasket.
Next, I noticed that the piston skirt was barely striking the engine case on the down stroke like Colin suggested.
So, I went to my friend's shop and sanded down the piston skirt considerably, and notched the corners to make sure they would not hit the case anymore.
I took my spare kickstart korado motor to the shop also and port matched the engine case tot the Athena kit! Came out great and I heard and felt an immediate difference. WOW.
But still, a loud metal sound coming from the top end.
I should note that the metal sound gets louder as the engine warms up. It is loudest when going very slow or idleing. At speed it either quits making the sound, or I just can't hear it.
So I thought next of piston slap. Foward and backward... like a loose wrist pin.
I compared needle bearings and wrist pins (stock and athena provided) and found one needle bearing to have a bit more play than the other, so I went with the tighter of the two.
Still making a lound metal pinging sound that I just can't believe is the metal reeds.
The only thing left for me now is to remove the cylinder and piston, put them together and check to see how well the piston fits inside. I think the piston skirt is rattling up and down the cylinder.
Either way, this sucks.
I feel like I'm gonna break this 250 dollar kit everytime I run it up and down the street.
I took off work today to figure this shit out.
I'm going into the garage right now.
I hope my Simonini comes in today so I can smile about something moped related.
Talk to you all soon.