The piston that came apart was a Yamaha piston, I just put the other one next to it so you can reference it. This was a result of riding it half a mile after the rod disconnected itself from the piston. There wasn't any strong vibration coming from the engine and I didn't feel like pushing it home, so i lugged it back on one cylinder. In hindsight I wish i would have shut it down and pushed it back.. It is at passion right now and I am waiting on Jim to call me and let me know how much damage it did. The funniest thing was when I pulled the head off both pistons were at TDC.