hubs intentionally one bearing short on each side?
12-09-05, 09:04 AM
#26
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Can we keep this discussion focused on the technical question here? I realize that there are some low-end hubs with retainer bearings (I repacked one last night for a friend) but they're not what this discussion is about.
You're right about there ending up a "gap" (i.e., the bearings don't stay equally spaced in this arrangement), so it's quite possible that the bearings rub up against each other nearly as much as with a full complement of bearings, so there's really little reduction in bearing-on-bearing friction, thus negating the advantage of one-less-bearing.
However, I'm pretty sure you're wrong about the gap "migrating" to the highest-stress area. For the simple reason that the ball bearings roll between the cone and the cup, meaning that they're always going around and around... so the gap would be going around and around too. This the biggest disadvantage that you point out, probably isn't.
Originally Posted by bikebros
By removing a bearing, you end up with a group of bearings all touching, then one spot where there is a gap. This gap migrates to the loaded side of the hub (the bottom), forcing the remaining bearings to come into loaded contact with adjascent bearings - so there is still contact. If anything, by having one less bearing, the loads placed on the bearings are shared by one fewer bearing resulting in an extra load being carried by the remaining bearings - causing premature bearing/cup/cone wear.
However, I'm pretty sure you're wrong about the gap "migrating" to the highest-stress area. For the simple reason that the ball bearings roll between the cone and the cup, meaning that they're always going around and around... so the gap would be going around and around too. This the biggest disadvantage that you point out, probably isn't.
12-09-05, 09:27 AM
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If it were me, I'd add an additional bearing to fill up the gap. Just make sure the bearing truely fits in there. I'm not sure if the extra bearing would add extra rolling friction or not, but I'm pretty sure the extra bearing will help distribute the stress over a larger area which is a good thing overall.
12-09-05, 11:32 AM
#28
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Originally Posted by Nessism
If it were me, I'd add an additional bearing to fill up the gap. Just make sure the bearing truely fits in there. I'm not sure if the extra bearing would add extra rolling friction or not, but I'm pretty sure the extra bearing will help distribute the stress over a larger area which is a good thing overall.
Last edited by simplify; 12-09-05 at 11:42 AM.
12-09-05, 12:22 PM
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I don't really understand what the "debate" on this thread is about. I thought it was obvious to anyone who's ever taken a ball bearing assembly apart that yes, there's a gap between two bearings if the rest of the bearings are closely spaced. The gap shouldn't be large enough to fit another ball into the assembly......It seems obvious that engineers figured this out a LONG time ago, and that this is the proper way for a ball bearing assembly to be put together. If you find a loose ball bearing assembly that has room enough for another ball to be put in, then chances are whoever serviced the bearings before had a problem with FOFARA balls.......(FOFARA: Fell On Floor And Rolled Away).
