Has anyone ever seen this before, and if so what caused it?



I bought a used 2001 gs500 this past september.  I am the 3rd owner, and the 1st owner laid it down  on the opposite side of the cracked cam caps.  I am giving the previous owner the benefit of the doubt in believeing that he didn't know when he sold it to me.  I was going to get the valves checked by a local shop and they let me know the deal.  Rather than having them replace the whole head I did the work myself.  It certainly helped me get to know the bike more, but at a cost.  I ended up buying a complete head from a slavage yard and just replacing the two cracked caps after using plastigage to make sure the journal bearing clearances were in tolerance.  Needless to say I have a complete head (including cams) that I am selling minus 2 cam caps.  
I was just wondering if anyone has ever seen this before.
Since this is my first new tpoic post I just have to say this site kicks ass!

Seen it, i believe over tightening is the culprit.

agreed... the guys should have bought a torque wrench