Weird hub problem

neeb
neeb Posts: 4,470
edited January 2014 in Workshop
I have an odd problem with play in a front hub. The wheel is a Reynolds 46, I think the hubs are re-branded DT and supposed to be decent quality. The wheel is more or less new or at least little used.

The problem is that when the wheel is fitted and the QR done up tightly, there is a little bit of sideways play in the hub. It's only very slight and mostly not present at all points during the rotation of the wheel, but it's annoying nonetheless. The odd thing is that after a bit of experimentation I've found that the play is only present when the QR is done up tightly, and is more or less proportional to the tightness of the QR. No play is detectable by pushing the ends of the axle hard with the wheel off the bike, and it's practically absent with the QR done up almost tight enough but not really tight...

The problem is independent of the type of QR used and occurs (to some extent at least) with the wheel fitted to different bikes. None of the bikes have similar problems with other wheels.

The hub design is very simple - just cartridge bearings pressed into the ends of the hub and held in place with one-piece end caps that screw onto the axle and also incorporate the contact surfaces for the dropouts. So the bits that slot into the dropouts are not the ends of the axle, rather they are part of the end caps that hold the bearings in. There appears to be no way to adjust bearing load.

The only way I can get my head around the problem is to assume that the contact surfaces on the end pieces that press against the inside surfaces of the dropouts are not completely parallel to each other when the end pieces are screwed on, so that when they are squeezed together hard it places uneven load on the bearings...

Any other ideas? Strictly speaking the wheel is still in warranty but I really don't want to be bothered with returning it (international shipping, also the rear wheel is being rebuilt on a powertap and I might need to return both). Could I get replacement end bits from Reynolds or DT and would that help, or perhaps if I could find out where the asymmetry was I could file down the contact surfaces appropriately?

Comments

  • majormantra
    majormantra Posts: 2,094
    The ends of the endcaps are sitting proud of the fork dropouts are they? That might cause odd behaviour.
  • neeb
    neeb Posts: 4,470
    The ends of the endcaps are sitting proud of the fork dropouts are they? That might cause odd behaviour.
    No, they're normal in that they're recessed slightly from the outer dropout surface when the wheel is in place.