Trouble getting the right cup and cone hub adjustment

Question

I have a pair of Shimano XT wheels and recently had issues with the hub on the rear wheel requiring new cones and bearings. These were fitted carefully but I've had issues getting the right adjustment tightening the cones.

On the one hand I can tighten it to a point which effectively prohibits rotation, and there is no play. But to get the hub to anything close to a smooth rotation I get a tiny amount of play. I have experimented extensively and cannot find any way to balance not having any play with having smooth rotation - in context smooth means turning cleanly, I realise there may be some friction, particularly with new parts. Conversely when I loosen so there is just a hint of movement I get very smooth rotation.

I've been testing with very small increments in tightness - probably around 3 degrees at a time.

The only thing I can think of is that I've used a general purpose grease rather than a hub bearing specific one, but I would expect that to be a difference between degrees of smoothness, rather than the difference between working and not working.

Can anyone provide any tips or suggestions as to how to address this?

Many thanks

Answer 1

Getting the adjustment right is sometimes difficult and is as much art as science. I rebuild lots of old bikes, and frequently have to rebuild wheels. Here's what I do...

First, be sure to work from one side. Normally the non-drivetrain side; that way your axle will stay centered. Clean everything up and inspect carefully. Since you've already bought new cones... Should be no problem. The difficulty, as you note, is making the final adjustment. You can get everything all set up so that it's apparently perfect. Then you apply the cone wrench to hold everything in place and tighten the locknut....And it's too tight. The problem is that the axle itself will tend to move when you tighten the locknut. So...When I get everything set to tighten down, I then clamp a big pair of vise-grips on the other side of the wheel, and hold the thing in my lap so that the vise-grips are held in place by my knee. Then, you can hold the cone in place and tighten the locknut with little chance of the axle moving. As to the exact adjustment.... It's always been the paradigm that if you have QR skewers, you leave the adjustment so that there's just a tiny, barely perceptible amount of play so that when the skewers are tightened they take up that slack. I've never done it. I always set mine so that the axle rotates freely and there is no perceptible play. I also don't tighten my skewers nearly as tight as all the "industry" guys recommend. Don't think it's necessary.

Answer 2

It can be frustrating to be in this position. I've finally learned the trick of instead of tightening the lock nut into the cones, back tighten the cone against the locking bolt. That is, get it so it has no play, but a little resistance and back the cone up into the locking bolt

As M. Werner says, a lot of online instructions say a little bit of play is made up for by the quick release and this may be just the thing for you. You have to wonder, though, after all the careful adjusting, why would we rely on this inexact method?

Answer 3

The lever between the bearing surfaces and the rim is quite large - a small amount of bearing play translates to quite a lot of movement at the rim. And bearings need a certain amount of play. Anything less than a millimetre of movement at the rim is acceptable IMO. Not ideal, but acceptable.

I assume you cleaned the cups, cones and axle before you started? Residual grit will make this difficult, as well as causing premature wear. When you do this look for signs of wear on the cups. If they're worn you might be able to get new ones, but it's likely you'll need a new hub (usually meaning a new wheel).

Technique when adjusting the cones is also important. How are you holding the axle when you're adjusting the cones?

Also, remember that the clamping force when you fix the wheel into the bike is enough to change the bearing play. Especially with single-speed or hub gear setups where people often overtighten the axle nuts. Usually the reduces the play/tightens the bearings, but if your axle is nearly broken it could loose them. If you didn't get a new axle with your new cones it is worth doing so, if for no other reason than guaranteeing that the axle is straight.

Answer 4

It means that there are microscopic imperfections in the bearing surfaces. It's a very common problem, especially with old or cheap parts.

You can try buying new cones from another company, and see if you have better luck. But if you've had these hubs for a while, then it's possible that the problem is with the cups, not the cones (I assume we're talking about the traditional type of hub, where the cup is a part of the hub body). In that case, there's nothing to do but replace the wheels - or, if the play in the bearing is still small, just live with it.