New cylinder eating rings!

[Firehawk989]

So I got a new Italkit cylinder kit for my Hyosung Sense 2T. Installed it, tried to start the scooter, and it ran poorly for a little while then made a loud click from the engine and stopped.

Took it all apart, found a broken top ring. Replaced the ring, put it all together again, started, ran ok, took it for a test ride and it ran around fine for a while. Then I left the back roads and tried to get it up to around 50km/h; again loud click, sputter, dead, compression gone. Probably another broken ring!

I didn't see anything wrong with the inside of the cylinder when I took it apart. Could the porting be done wrong or something? I didn't have any trouble installing the cylinder, and everything went together fine with no parts out of place. WTF is wrong with this thing!?