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I've read in many different places that if you take a hub apart and see damage on the cups, cones, or bearings (may god have mercy on you if your cups are damaged) That they must be replaced.

I recently bought a used bike that had a lot of miles on it. There was a tiny bit of damage on the cones in the rear hub, concentrated within about 1/8 of the race.

That seems to make sense: The wheel spun very freely, so it was well-tuned, and the top of the cones took very little wear. The damage developed where the rider's weight was: on the bottom 1/8 of the cone.

So I'm wondering if I can get away with simply rotating the axle so that the cones have the damaged side up, and the good side down. That way the damaged side will be supporting an insignificant amount of weight (and not messing the balls up), and my ball bearings will have the pressure on them while they're rolling over the good part of the cone.

Does that sound like a hack that will work?

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    In theory that will work. But replacement cones are readily available for most size bearings, so consider replacing them. Commented Nov 27, 2014 at 18:10
  • Replace the cones. If the bearing is properly adjusted the load will be equal on each single ball.
    – Carel
    Commented Nov 27, 2014 at 19:23
  • Right, but only when the bike's not being ridden.
    – BSO rider
    Commented Nov 27, 2014 at 19:42
  • Replace the bearing as well - they are a couple of dollars, it will be cheaper and more reliable in the long run.
    – mattnz
    Commented Nov 27, 2014 at 22:26
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    It would work, but you'd have to be very careful that the axle did not rotate at all in the frame. You'd probably want to mark the end of it to make sure. And check it regularly. But you'd save nearly $10. So it might make sense if $10 is a significant amount of money to you.
    – Móż
    Commented Nov 28, 2014 at 0:12

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No it would not work. The pitt didn't form just because it was on the bottom, the pitt formed either because the cone came loose, or an abrasive got into the bearings.

There's an equal amount of force being applied to the top of the cone as there is to the bottom when your hubs are properly adjusted. Think of the components in a hub as a stack, the cup is both the top and bottom of the stack, and the balls and cone are sandwiched in the middle, put some weight on the top of the stack and the force is going to be evenly distributed through everything. Your theory would only work if you left some play in the hub, which would only destroy the cones faster.

Replace the cones and balls, they're cheap, and I imagine that you don't want to have a reputation of being a hack mechanic.

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    There is a flaw in your logic. The bottom of the cone always has more pressure on it than the top of the cone. If your hub is well tuned, the top of the cone should have no pressure on it, and the bottom should have the weight of the bike and rider.
    – BSO rider
    Commented Nov 28, 2014 at 16:12

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