Bearing drag from tightening the cassette?

[Lewis Moon]

I have a couple of sets of wheels built with BHS hubs (SL210 Campy rears). On one of the hubs, for some inexplicable reason, the bearings bind when I tighten a cassette on the freehub. With the cassette off or fitted with the lock ring just to hold on the cogs, the main bearings turn pretty smoothly. If I tighten the lock ring (even just a bit), the bearings get tight and have a LOT more drag. I致e had the hub apart several times and all the bearings, hub and freehub, roll smoothly. I知 baffled. I can稚 think of a reason why this would happen. Tightening the cassette lock ring should have no effect on the internal bearings. All of the forces should be isolated to the body. I致e tried different Campy and Miche cassettes and it happens the same way on all.
Any ideas?

[kramnnim]

Unlikely, but could the lockring be too long, and bottom out on the outer bearing?

[Mark McM]

Actually I think that's the most likely.

Quick test: Thread the lockring onto the freehub without a cassette installed. Turn the lockring until you just start to feel some bottoming-out resistance. Is the freehub dragging? Unscrew the lockring a half turn. Is the freehub drag gone? If so, my guess is that the lockring is bottoming out against the bearing.

If this is the case, than it is probably not a case of the lockring being too long, but the bearing not being installed in the freehub to the correct depth.

[Lewis Moon]

Actually I think that's the most likely.

Quick test: Thread the lockring onto the freehub without a cassette installed. Turn the lockring until you just start to feel some bottoming-out resistance. Is the freehub dragging? Unscrew the lockring a half turn. Is the freehub drag gone? If so, my guess is that the lockring is bottoming out against the bearing.

If this is the case, than it is probably not a case of the lockring being too long, but the bearing not being installed in the freehub to the correct depth.

Two different lock rings, one considerably shorter than the other, no difference.
Brandon at BHS thinks it might be a missing internal spacer. Every once in a while a hub will come w/o one.

[kramnnim]

He must be thinking of the spacer that is trapped between the two bearings in the freehub body?

[buldogge]

Nope...Make sure the thin .8mm spacer is behind the FHB, on the axle, when you pull the FHB off. I got one missing the spacer one time and Brandon sent me a couple.

-Mark in St. Louis

Two different lock rings, one considerably shorter than the other, no difference.
Brandon at BHS thinks it might be a missing internal spacer. Every once in a while a hub will come w/o one.

He must be thinking of the spacer that is trapped between the two bearings in the freehub body?