Topic: Are bearing retainers on hub necessary?

[rhinoracer]

Modern bikes don't use them, or at least the 2001 R1 and 2000 DRZ fronts I looked at.

[Alan F.]

Darn good question, it'd seem that when everything's in and tight that the bearing retainers wouldn't be useful, I can't remember what the wheels that use the retainers use for axle seals though, maybe the retainers act somewhat as seals too?

[Bodi]

The retainer is absolutely required on these wheels. It is the only thing that locates the wheel hub side-to-side. Without it the wheel could slide off away from where the retainer should be, the unretained bearing would then fall out of its bore, and the wheel would go totally wonky... and you would crash and die.
I don't know the workings of the hubs you mention, but there are many designs that don't use retainers.

[754]

How can the unretained bearing slide over Bodi, if the center spacer and all others are installed?

[paulages]

How can the unretained bearing slide over Bodi, if the center spacer and all others are installed?

the spacers will bear only on the inner race, no? this is essentially locking down the axle, bearings, and spacers, but the retainer locates the outer race to the hub. maybe i'm thinking about this wrong, but it seems like any lateral thrust from the wheel would be transfered only through the ball bearings, or worse- the hub would float on the bearing assembly. if these were tapered bearings, like in car hubs, it could take the thrust (but the second possibility would still be an issue). maybe there isn't all that much side thrust on a motorcycle wheel? sure seems like there would be...

[754]

Only on a sidecar, and maybe sliding sideways, while not leaning.

If the center spacer, is too long, then the bearings can move around a bit.. but if both outer races are against the shoulders, where can they go?
 Morris mags, Bearing plates on the outside, with lip to inside, plus a center spacer.

[paulages]

Only on a sidecar, and maybe sliding sideways, while not leaning.

If the center spacer, is too long, then the bearings can move around a bit.. but if both outer races are against the shoulders, where can they go?
 Morris mags, Bearing plates on the outside, with lip to inside, plus a center spacer.

isn't there only a shoulder on the non-retainer side?

[754]

if there is not a shoulder you would need a retainer, BUT it would then NEED a torque value to prevent excessive pre-loading  of bearing.

[tlbranth]

Ball bearings can handle radial and thrust forces. I don't see why the retainer is necessary other than the fact that the original bearings weren't "sealed". They were "shielded". There may be some reason, though, to hold one of the outer races still. Probably better to give a nod to the engineers who came up with it eh?

[Bodi]

The bearing opposite the retainer is free to slide as far into the hub as it likes, the bore is not stepped. It will eventually fall off the end of that bore inside the hub if you want to push it that far, but that would be a bad idea. Without the retainer, the bearing that should have it can move out of its bore while the opposite one moved into its bore.
You can make up the spacer-bearing-inner spacer-bearing-speedo drive sandwich without the hub if you want, tighten the axle, and mount it on the forks. The rear is a bit different because of the sprocket carrier but again you can make it up without the hub if you feel like it.
The inner spacer just makes a solid stack of the assembly, so the axle nut is not breaking the bearings apart by putting axial load on them: this type of ball bearings are not designed for axial load. Automotive axles have tapered roller bearings that are.
Without the retainer the hub will slide side-to-side relatively freely, limited by the tightness of the hub bores on the outer races. Some will know my ideas on the bores, that the beareings should be a snug sliding fit and no require a press or major force to install... whatever, the hub will be free to move axially without the retainer. I don't know if it would move enough for one of the bearings to come out of its bore bur otherwise it would move until two parts not intended to touch, do.

[754]

Actually I have not had Honda rear hub bearings out in decades, I should look at one on the drawing. Had a front apart lately, and it was double lip if I recall correctly... as are most hubs.

And yes Honda does use sheilded inner bearings, so part of the retainer function is somtimes sealing. That can be eliminated by double sealed bearings.

 Tapered rollers do handle axial load, but most require clearance, so center spacer length on bike hubs is crucial.

 There is some hubs that dont use retainers.

[bryanj]

But dont the hubs without retainers use circlips?

[754]

Look at spool hubs on;
 Choppers

 Flat trackers

 Bicycle

 Drag bikes

 Consider this a hub has a bearing seated against a shoulder on ech side & the center spacer sized correctly, and in place. Now add outer spacers, insert in swingarm, torque up.
 Now, try moving the hub sideways.

 IF one of the bearings is not against a shoulder, then it could possibly move.

[Bodi]

"Ball bearings can handle radial and thrust forces."
Not exactly true. Ball bearings can be designed for radial loads, for axial loads, or (poorly) a combination of these.
The single row 6xxx series used in our hubs are called "radial ball bearings" in bearing catalogs. They are designed to carry only radial loads. The radial load capacity is fully specified, usually with maximum static and dynamic loading specified. There is no specification for axial load because this type of bearing should not be subjected to axial loads and although minor axial load won't immediately destroy it, this will shorten the service life of the bearing.