IMS roll, ya got me all confused, you bought an initially good running bike, then immediately blew the top end, replaced it, then blew the top end a 2nd time, replaced it a 2nd time, and now you're on your 3rd rebuild ? How did the cyl look when you did the first top end ? Did your "buddy" mic the bore to see if it's in spec ? Did you at any time take compression readings ? If you feel gouges in the cyl bore with your fingernail, you need to weld and replate the bore (OEM nickasil). If you have a Wiseco/ sleeve combo those can be over bored. Seems top me like your simply blowing top ends, and slapping parts back together without carefully diagnosing to ROOT cause of the failures (which IMO is NOT your jetting) Yes you were a bit lean, but not lean enough to completely blow a top end...