This ^^^^.
Most stories you hear are about someone who rode the bearing until is practically exploded and this usually damages the end(s) of the spacer(s). Most Buell owners are cheap and arent going to spend any more than they have to, and also most dont understand what that spacer actually does in the wheel (I had one person tell me they were just going to carefully file off the boogered up end of a spacer until it looked good). All it takes its to be a millimeter or so out of spec for the inner and outer races of the bearing to be forced out of spec when the axle is torqued down... which kills ANY bearing.
Try installing the bearings without the spacer and see what happens.