Ralph, You have given me a lot to think about w/ this feedback. I'm now wondering if this was a self created issue. 1) In referring to the "spacers", do you mean the middle 3-4 inch tubing that keeps the left/right bearings from moving inward ? it's not crushed but there seem bruising along certain areas of the pipe. But how could that be caused by the axle? I will get it replaced at the local KTM w /new bearings in Athens on Friday just in case. will take a picture of the bruising along the pipe length that I noticed in Armenia. Or do you mean the outer two aluminum spindles that caps off the hub ( between the hub and swing arm). Those had to be polished down abit from time to time as they seemed to show some scaring / wear /tear that kept it from sliding in / spinning smoothly into the bearing. 2) The several times I watched the shop guys replaced they bearing, they would use another bearing over the new bearing, a solid cylinder tool, something else that they would use to evenly knock / distribute the force onto the bearing into place (contacting the outer race); never directly hammer to bearing so I think mostly likely not #2. 3) I haven't thought about #3. I didn't have any issues w/ the OEM rear that had 12K miles when I first purchased the bike used (2015), I put another 12k miles on it.. so 24K miles on original OEM rear/ same bearings. Hadn't looked if the swing arm was straight or not ? Would I just use a straight edge to measure if the two mounting bolt points are parallel / even ? In truth, the first time I started feeling if something was wrong was when the custom 18" excel wheel was sealed, new bearings replaced (KOYOs), and new Mitas tire E-07s, it would make oscillating humming noise between 50-65 miles every 3-5 minutes. I was hoping it was the tire but now believe it's related to bearings as it was still there somewhat w/ the 2nd new tire.. only disappeared w/ new bearing replacement. 4) Now this point might be something to consider. I don't carry a torque wrench but the rear bolt is suppose to be tightened 100 nm of torque. Somewhere during the trip, when I was adjusting the chain, when I released the nut one time, it felt a bit loose, that it didn't hardly need any pressure to release. Started to worry I wasn't hand tighten enough to 100 nm. From that point forward, I would hand tighten then use my foot to push down a quarter turn or so. I do now recall hearing a metal popping noise on two occasions where when making final tightening w/ my foot. So perhaps, we might be on to something??? LOL I do recall cringing abit when it popped... ha.. could that be it. In referring to the left bearing being loose during the install, that was only witnessed that one time in Armenia. The other two times ( once in Mongolia, once in Russia), it was difficult / tight to install so not sure how it would have gotten lose / widened out permanently like that. I keep thinking I should've taken the 1200GS w/ shaft final drive, but of course, that has it's own set of issues that would probably be harder to address..