I just bought a used 660 from a guy and on my second time taking it on the trails, the rear bearings got destroyed.(looked like original bearings) Took the carrier to a Yamaha maintenance shop and had them press new bearings in. I put the axle back together and took it back to the trails the following weekend and within 2 hours in the trails, boom, bearings gone again. Anyone got any clue why bearings would keep going out on me? The old bearings left some scratches on the middle of the spacer, but other than that nothing really wrong with the carrier. I'm lost and pissed because a whole gang of us are trying to go out again next week,I surely don't want to be left behind... Any guesses??