Fresh engine probably 30gals and boom

[superjetguy]

Hey guys pulled off my head today just curious what she was looking like after I broke it in. I rebuilt my carbs last night because the last time I was out it lost a little power and the carbs were really wet and leaky. But sure enough I pulled the head. The rear cylinder was totally roached.. I'm having bad luck with this engine. Luckily I just picked myself up a spare round nose.. Maybe I jinxed myself

so I'm looking for a engine or a top end. Also need a head anyone let me know what they have

 

[badvinny]

One pic isn't much to go on, but the bottom of the transfer port looks like the sleeve is cracked, something came apart like a bearing cage or reed valve breaking apart. Topend needed atleast.

 

[superjetguy]

I suspect I lost a circlip. But why is the other piston and cylinder still messed up so badly after such few hours.

 

[Balduccimoto]

Looks like you seized that a few times. At operating temperature those pistons are a near press-fit in the bore. The only thing stopping the piston from kissing the cylinder wall is the oil. When oil reaches a high temperature it flashes, burns and the piston meets the wall. High heat could possibly be a combination of overheating, lean mixture, high compression, advanced timing. Or it could be improper piston-cylinder wall clearance.

What happen in the worse cylinder? It looks like something let loose there.

 

[Old_Skool]

In that last pic it looks like the wrist pin circlip worked it's way out. Hence the deep grooves in the cylinder wall.

 

[J.s1027]

Looks like a wrist let loose

 

[MADMAT]

OUCH!

 

[flgliderpilot]

There is a curved groove in the side of the piston shaped like a circlip.. coincidence?