Cup and cone bearing adjust

[marciero]

I've always adjusted cup and cone bearings to just seated and maybe back off an eighth of a turn, then lock down, such that there is no play, or maybe just the very slightest bit of play. I guess if there is no play there is not telling if it is tighter than you want. In any case, I'm not convinced that installing the wheel in the dropouts tightens things further, in which case we want a little play. Also, might it be desirable to have just a bit of play when installed? Maybe that would facilitate the flow of grease. Also, I would bet that binding begins to occur exactly at the threshold of no-play in the adjustment. So if that is the case we want a tad of play.

Basically I'm talking myself into adjusting for more play here. Curious how others do this, and if practices vary.

[oldpotatoe]

Originally Posted by marciero

I've always adjusted cup and cone bearings to just seated and maybe back off an eighth of a turn, then lock down, such that there is no play, or maybe just the very slightest bit of play. I guess if there is no play there is not telling if it is tighter than you want. In any case, I'm not convinced that installing the wheel in the dropouts tightens things further, in which case we want a little play. Also, might it be desirable to have just a bit of play when installed? Maybe that would facilitate the flow of grease. Also, I would bet that binding begins to occur exactly at the threshold of no-play in the adjustment. So if that is the case we want a tad of play.

Basically I'm talking myself into adjusting for more play here. Curious how others do this, and if practices vary.

Depends on the hub design but there is little doubt that clamping a wheel into a frame or fork with a QR that is tight enough so the wheel doesn't come out, DOES increase the 'tightness' of the cones on the bearings. Why you adjust with a wee bit of 'play' off the bike, clamp in, no play..spin the wheel..with hand on seat stay or fork leg and feel nothing but smoothness.

[jamesdak]

I leave a tiny bit of play I can feel with my fingers on the axle while on the bench. It seems to translated into a free spinning wheel on the bike with no play felt when mounted with the QG tightened. If I can detect play in the wheel with it mounted (by grabbing the rim/tire and trying to move that) I always preload more.

[thwart]

Same here.

As a matter of fact right now I have one bike with a very tight front QR… just too lazy to take it off and tighten the bearings ‘the right way’ another millimeter or so. It’s a 7810 Dura Ace hub… the more recent Campy cup & cone hub designs can be adjusted while on the bike… QR tightening has essentially no effect.

[David Kirk]

Here's an interesting thing to try if you feel inclined - adjust the hub as you would normally and then put a pair of dropouts on hub and lock down the skewer. Now spin the axle to see how it feels. All too often it will feel tight and notchy. You can then readjust until it spins smoothly even when the skewer is tight.

Now I know that most people won't have a pair of dropouts just sitting around to do this with but you can put a small stack of washers on the axle instead and it will work the same way.


dave

[marciero]

Thanks for the insights all. Looks like I will probably be backing off a bit on the adjust!

[redir]

How does tightening the skewer on the two stop nuts of the cup and cone system tighten up the bearings?

[David Kirk]

Originally Posted by redir

How does tightening the skewer on the two stop nuts of the cup and cone system tighten up the bearings?

As unlikely as it sounds it compresses the axle end to end and therefore decreases the distance between the cones on the axle...which tightens the bearings.

dave