looks to me like something passed through the air-filter and stuck it self to the rings ,m grit , maybe sand or dirt of some sort, these chrome cylinders are super delicate , a little heat and a foreign object would wreak havoc in one of these cylinders .
@Wags what is "pitte?" Or is that a misspelling? It does have a lot of build up on the top of the piston. I thought it was normal, especially since I like to run a high ratio of oil. Besides what you already stated, what are signs of irregular Detonation? Last thing I need is an injury!
Misspelled. Looks pitted not pitte. If the top of your piston is smooth then it's just the picture that's bad. But if there are a bunch of little Dent looking things especially around the edges normally on the exhaust side then I would say detonation or running extremely hot.
@Wags oh gotcha. No it's not pitted. The top of the piston is smooth all the way around, aswell as the surface. That jug is shot but it still rides Excellent... Definitely will need a replacement soon. I would have done that day that I took the pic. But there's gotta be some kind of glue/sealer on that bottom gasket. Was stuck on good and would not budge. Gonna have to try harder next time.