The dealer suspected that when I had the rear tire changed because of a flat a few months earlier, the tech had over torqued the rear wheel axle. The tire was replaced at a Honda shop that was not an authorized Kawasaki dealer. The Kawi mechanic said the Concours is the most sensitive bike on the road to torque specs. Just a little bit off either way, especially on the axles, and you can have problems.
that "dealer" hasn't a clue.
total bull-hockey.
when you tighten either the front or rear axle, WITH ALL THE PARTS CORRECTLY INSTALLED, it's virtually impossible to "damage the bearing" by over torqueing it.
The internal and external spacer stackup, and the axle, compress against the center race of the bearing, once that's solid, it can't get "any more solid", and you surely aren't gonna compress those spacers with a hand held wrench.
If someone were to compress the assembly WITHOUT one of those spacers, then yes, it COULD damage a bearing, and that is likely the cause... and when the "technician" noticed the spacer laying on the floor, he installed it and zipped his lipz.... nobody saw him, he can lie all he wants.
just my opinion.
or, the bearing was bad from the start.