Hi guys, I recently stripped down my nieces bike because it was 'hard to ride' I took the rear wheel off and its near impossible to spin the axle by hand sometimes. It spins then slowly binds almost completely then eases off again. I've stripped the hub and cleaned/oiled the bearings then reset the cones and the only way I can loose the rub is to have the cones so loose that the wheel walks between them, which is not really rideable. Kinda feels like the axle is bent Should I replace the axle or cones or bearings (or all). Or have I missed something obvious?