A few weeks ago, going down a fire road, the bike locked up. It would restart & click in gear, but wouldn't move. Dropped it at my private mechanic & he had an incredibly difficult time splitting the cases. He says that once open, the gears & parts had overheated & gotten so hot, that all the gears had turned black & they were difficult to pry apart. He thinks there probably wasn't enough oil in the bike, but I've always done my own oil changes & it's always the full quart. So he believes I should get an entirely new bottom end......being gears & engine cases, plus other bits n pieces. This would cost $3000, so he suggested a used 2005 bottom end off ebay. I don't know anything about motors, but is it really completely shot????? He says it's not worth risking using the old parts as they got so hot & may have warped or something. Anybody wanna weigh in on this????