i replaced what i thought was a warped brake disc on the front right hub. it had severe axial runout, about 2mm. brake pads were worn unevenly down into the metal. but after replacing the disc with a new one, it still has the same runout. i can't ride like this or my new disc and pads will be wasted. also, the hub was very hard to get off the splines. on the other side with the same disc mounted it's good. that hub slid right off and on. now, what parts may i need to replace? i don't know the history of this machine. pre-owned 2007 sportsman 500 x2. thanks.