XRS 159, Serial #437 manufactured in 10/06 (if i remember right on the date). I Broke it in cautiously, rode harder later last year after i made it passed the 400 mile mark. Lost bottom end bearing on friday at about 597 miles, i was on the trail, running scratchers with consistent snow on trail all the way....made it 15 miles before it piled up.....sounded like it was piling up behind the recoil (metal on metal bearing sounds, reminded me of a seizing wheel bearing). I was a long time skidoo fan, but this type of failure has never happened to me before....i'm thinking twice about continuing with them....thank god it happened on the trail and not 45 km's into the back country, or it would have beeen a chopper for sure. Anyone know if my new engine will be warranteed for another two years from install date?