Got home and immediately drained the oil which was dark grey to black, where it is usually a light honey color. Started tearing it down and one of the valve cover bolts was hard to get out and when I finally got it, the end was all chewed up. Pulled the plugs out of the cover, checked the timing and it was way off, not just one tooth.
Here is the weird part. Both of the circlips were out into the clearance areas where the lobes rotate, and all munched up. One of the cam lobes on the intake side is tore up with half the clip gone and the other half wedged into a gap. The exhaust side clip was crammed into an opening, bent up, but still in tact. The cam cap bolts were still tight.
I've gone through every scenario that I can think of and the only thing that I can think of is that the circlips fell out while I was putting the caps back on. I don't see how they could have come out if everything was put together correctly. The confusing thing about that is that the odds of getting 5 hours out of it with the clips bouncing around in there seem fairly slim.
In those 5 hours the bike ran and started perfectly and the motor was actually quieter, right up until it imploded.
Will be doing more exploratory surgery today, but wanted to get an idea of what may have caused this.
Edited by Greg_T_M, April 10, 2010 - 08:29 PM.