From what I remember (this happened months ago), a rod let loose. That guy was making good power. At those power levels, they're close to what the H2R made....... and if you look in the service manual for that bike, the intervals to check rod bolts and such are way more frequent than the road-worthy H2.
Those bikes are wild. My bf had a stretched 275hp H2 running on E85. I've never felt power quite like it before! It actually made me consider the new H2 SX as a road trip bike!