Engine troubles - OS 50 hyper

The OS 50 hyper had been properly tuned and running well for 13 gallons, yet out of the blue, the piston ring broke for no particular reason. It happened when i ran dry the engine at the end of the day's flight which i have always done. A 'Ting' sound was heard and i knew something was wrong.

Piston ring broke and chip off abit of the piston

Engine was ran rich and very new

Bearings after 13 gallons

So i spent 50 bucks and got replacements

I took time and carefully changed the parts. Made sure all was working properly before refitting it back to the heli.

I was looking forward to run-in the engine again, but WTF the ring broke on the first crank??!?.
i was very sure the parts was installed properly. This time the damage was worse than the first time, the inside of the crank case got scatched.

Crap, was so disappointed that i decided to try another engine. Just received the new engine in. I look forward to testing the new YS , will be back with review once i get a few gallons in.