Posting this for a friend, I help my neighbor work on his bike. We've put 4 sets of rear wheel bearings in his 2016 250sx this summer, they wear out before the tire does. Stock, all balls, pivot works and cheap local bearing shop ones were all tried and there was no difference in how long they last. We put a set of skf ones from the local bearing shop in it last night to try them. I've install lots of bearings in bikes, were putting them in right and I don't have issues with any of the other bikes I work on. We took the seals out of a couple sets and greased them but it didn't help. The spacers, hub and seals all look fine too. The bearings are full of muddy water when we change them but they have play in them so its hard to tell if it got in before they had play or right after they got sloppy as they don't seal at all with play in them. Is there a better replacement bearing? I seen the MSR upgrade kit for the older ktms but it doesn't work on the 2016, is there something like that for the newer bikes yet? I'm used to kawi's and yamaha's, they have 3 bearings or really large ones on the sprocket side compared to the ktm, not knocking ktm, its a great bike but the rear wheel bearings are tiny.