Shimano hub cones - common/interchangable?

[Sweep]

This
https://www.chainreactioncycles.com/shi ... 1added240b

Prompted something I have idly wondered about on the fraught question of searching for spare cones.

Last time I had to do it I fortunately managed to find a new hub on discount and just swapped the internals.

Seem to remember brucey once saying (profound apologies if misquoting) that despite the dazzling array of cone spec numbers from the big S there were actually very few - lots so similar not a big issue.

If so I don't suppose there is a handy equivalence table lurking anywhere?

[531colin]

https://wheelsmfg.com/products/hub-parts/all-cones.html

[Sweep]

thanks colin.

was once looking at buying one of their cones but had the impression they were quite hard to get hold of in the UK.

If (from a quick look) I have it right that table just tells you which wheels manufacturing part you need for each hub?

So if you want a shimano part/to raid another full hub, you are suggesting look for hubs which take the same wheels manufacturing part?

[Brucey]

yep. Shimano cones inly have a few different profiles, a few different screw threads, and mainly differ in length, finish, dust seals etc. With quite limited bodging capability you can make all kinds of cones work in hubs that were never intended to accept them. On the EV techdoc it will tell you the screw thread, (and the cone length often) and the number/size of balls that run on the cone. If these match to another cone then it is odds on that it will work, or can be made to without too much work.

FWIW the correct cones are often available; try searching for the part number. When you search, try to vary the punctuation in the middle of the part number, and try omitting the first and last digits. This will provide the most hits. SJS have a lot of different cones and also sell complete axles in some cases; not such good value as a whole hub, often, but pretty good.

FWIW cones ought to last a very long time. if you are having to replace cones often then something is probably wrong. The most common causes are

1) that water gets into the hub
2) that the hubs are set with too much preload (there should be slight free play that just disappears as the QR is tightened)
3) you are really being too fussy

IME if hubs of reasonable quality are packed with better grease and correctly adjusted they can go for 20000 miles without any attention whatsover.

However if you keep the factory grease/adjustment, they might go 2000 to 5000 miles before falling to bits.

cheers

[drossall]

Baker's Bikes in Bishop's Stortford used to be good for obscure cones, such as 1970s Campag and Shimano ones. Not sure what they can offer now.

[531colin]

thanks colin.

was once looking at buying one of their cones but had the impression they were quite hard to get hold of in the UK.

If (from a quick look) I have it right that table just tells you which wheels manufacturing part you need for each hub?

So if you want a shimano part/to raid another full hub, you are suggesting look for hubs which take the same wheels manufacturing part?

I suppose you could do that, but what I really meant was find a proper bike shop that keeps the "Wheels Manu. selection box" behind the counter.
As Brucey says, if you avoid riding in the sea and set the preload carefully (bit of play which just goes when you tighten the Q/R) then these things seem to last indefinitely; certainly reasonable quality ones, I have lots of XT hubs from the steel axle era in use.
I grease mine annually by backing off the left cone and squirting some fresh grease in; semi-fluid grease in the freehub bearing, because that must find its way into the freehub itself, and grease in all the others. I used to drill my hubs and pump them up with grease, I found the freehubs can run dry eventually.

[alexnharvey]

Where could one find a good explanation of the geometry of cup and cone bearings, how the curvature and angle of each is set wrt the other and the ball, how this varies with expected axial and vertical loads. Are the curved surfaces simple, constant radius or are they more complex with decreasing radii?

[Brucey]

its not as simple as it looks and anyway they vary in design. However in order to work the balls need to

a) contact across a diameter and
b) contact surfaces such that the normals from the contact point on both the cup and the cone surface are both coincident and good diameters across the balls.
c) the contact angle needs to be something sensible, bearing mind the loading on the bearing.

In practice if you assemble a bearing dry, with cone surfaces marked up, you can see if

a) the balls run in a nice narrow track on the cones and
b) if the bearing still feels like a bearing when the cones are least finger tight.

If it passes these tests the bearing is usually 'good'. If the track is wide and/or the balls start scuffing when the cones are finger tight, the bearing is 'bad'.

cheers

[alexnharvey]

Thanks Brucey. I can't quite articulate the question but essentially are the curves and angles designed so that as the loads go on the ball bearing wants to remain running on the diameter rather than scuffing, it's kind of self aligning.