Cylinder Cracks ???

[KX Newfie]

I've noticed some minor cracks / stress inside the cylinder transfer ports {not affecting the nikasil plating withing the cylinder.}
Okay....now what  
The top of the piston rim on the exhaust side let go, & cracked a ring  . But the cylinder looks okay aside from the points i mentioned.
I retrieved all the pieces from the broken piston rim.

Man up until now i was in love with this bike .... i want to saddle up again ASAP !!!

[Hillclimb#42]

 I saw pics with those cracks from stewart, I think. Not sure if you need to fix them first or if they are harmless the way they are. What kind of piston was it that came apart? Any idea about the cause or circumstances that may have caused it?  I'm pretty sure that the cylinder is not junk. The green love will be back once you have it back together.

[KX Newfie]

Believe me...i love this bike more then anything i've ever owned 
Not real sure what happened....it wasn't lean or anything.
I think the piston was a stock one.....Stewart would know.
I did notice however that when i went to drain the coolant a few days after that alot of air pressure was entrapped {first time i ever seen this  }
I used race gas that was about 7 months old ( it was opened 7 months ago} ...not sure if that would cause any such problems.
I may put a complete engine gasket kit in this motor....i did notice that i have lost a small amount of tranny fluid every now & then.
Although i have thought about just putting a new piston & top end gasket hit in 

[stewart]

i only use wiesco pistons....  most of the kx cylinders have casting lines on the intake bridges ..max power rewelds them from the cylinder face when the chrome is removed before replating ive never seenn them brake  after that..  exhast side of piston falure to little octane  or to lean  or back off stator timing  ,,you need at least 114 octane  with right fuel mix must run a b10 plug as well