Bearings . . . 'ball retainers' - does anyone know where to buy them?

[yashicamat]

I'm getting the bits together to do my own hub servicing, but having examined the Shimano techdocs page, it would seem that my touring bike hubs (M770 XT ones) utilise 'ball retainers' for 3 out of the 4 races. I'm at a loss to find these ball bearings (I'm assuming they're a whole unit, rather than reloading the little cage with new ball bearings?), listed on this diagram as Part 4.

Does anyone know where I can source these from? Googling doesn't reveal anything, except for other people asking the same question and not getting a response either!

Cheers.

 

[Cubist]

You should find them at any LBS, or even Halfords, but my question would be "Why bother?" All they do is make it easy to assemble, and as far as I know serve no useful purpose to the smooth running of the bearings. I'd just fit bearings without them.

 

[Andy_R]

You should find them at any LBS, or even Halfords, but my question would be "Why bother?" All they do is make it easy to assemble, and as far as I know serve no useful purpose to the smooth running of the bearings. I'd just fit bearings without them.

+1, but if you must, then Halfrauds have them with grease.

 

[yashicamat]

Thanks for the replies. So the thought is that just a higher number of normal bearings will suffice instead? As for the grease part, that would be surplus to requirements as my research suggests that marine grease is the best stuff for bearings and we have a canal in this town.

 

[Cubist]

If you count the bearings in the retainer that should do it. I'm not sure you'll need many more. I always buy two or three extras which I donate to the dust monster under my workbench anyway.

 

[accountantpete]

The bearing cages just hold the bearings in the position they would be in once the cone is engaged - they don't assist performance and are not necessary but do make life a bit easier by stopping the bearings falling out during maintenance.

Don't add any more bearings than the hub is designed for.

Any old grease will do - the performance of a hub is 99.9% dependent on the quality of the bearings and the races.

 

[yashicamat]

I've not actually dismantled the hub, but looking at the photo on the Halfrauds website, that suggests that the spacers in the cage take up quite a bit of space (compared with how much space there would be if just the bearings were inserted) - maybe I'm missing something, but if loose ball bearings of the same number that are in a cage were inserted instead, wouldn't a large gap be introduced into the race from all the extra space that the cage spacers would normally take up? Surely this would create uneven load issues within the race (I'm just thinking logically here, rather than going off any actual knowledge on the subject!)? To me it would seem logical to introduce extra bearings so the race was full in the same way that a race is that is designed specifically for loose bearings.

Ta

 

[Tim Hall]

If you're not using the cage, put enough balls in such that there's space for one more, IYSWIM.

What I do is splodge some grease into the bearing track, then put the balls in one by one using a pair of tweezers or thin pliers. Make sure they're in the right place by trial fitting the cone and giving it a quick twist.

If you haven't tweezers or pliers, try using a biro top, sticking the ball to it using a dab of grease.

 

[yashicamat]

Cheers Yeah that make sense, I think I'd seen somewhere (I forget where) to basically fill the cup until the final bearing wouldn't quite sit in the race (maybe I should try this with dry bearings first so I know how many are needed), then remove that extra bearing so there's a 2 or 3mm gap left when all the other bearings are touching each other. Does that sound about right?

 

[accountantpete]

Sorry but you can't put more bearings in the hub than the race is designed for.

(well you can but the hub will not function at best efficiency).

If you look at the diagram - specificallly the nearest No 6 - the bearings slot in from the near side and when it is assembled they will be touching each other with no gap.

 

[yashicamat]

Right, so looking at that diagram, it suggests that when a caged-bearing is used, there are a total of 11 bearings are there within the cage. Obviously they are evenly distributed as a result of that cage. What I'm trying to get my head around is if 11 loose bearings were put into that race, because there is no cage to hold them at equal distances, they could bunch up together, leaving a gap (and surely this would result in uneven loading/poor wear characteristics etc.).

The other way I'm looking at this, is for example in a non-caged bearing hub (one of which I dismantled yesterday), the bearings are all fairly snug to each other in the race with only a small gap left - this to me suggests that when the bearings are loose, the number of bearings should be sufficient to virtually fill the race?

Sorry if I'm being a bit dense . . . just struggling to get my head around this a bit.

 

[accountantpete]

It's not remotely easy to grasp -so you are not being dense.

The trick is to imagine what happens when the cone is tightened up.

It's perhaps best to think of the race and the cone as the two sides of a vice. If you put say a balloon in the vice and tighten up then it will expand where there is no pressure.

In more or less the same fashion when you put bearings in between the hub race and the cone and tighten up, they too will seek to expand. In this case they don't deform but rather take up any available space.

This is why very good hubs are so expensive as the design measurements have to be spot on.

 

[rusty bearing]

"The other way I'm looking at this, is for example in a non-caged bearing hub (one of which I dismantled yesterday), the bearings are all fairly snug to each other in the race with only a small gap left - this to me suggests that when the bearings are loose, the number of bearings should be sufficient to virtually fill the race?"

That about sums it up. The bearings that we buy in pots for the workshop are slightly magnetized so you can dip a fine screwdriver in to pick one up and place carefully in the greased hub. The hard part comes when you tighten everything up 'just so'. Might take a few goes but you'll get there.........

 

[tyred]

"The other way I'm looking at this, is for example in a non-caged bearing hub (one of which I dismantled yesterday), the bearings are all fairly snug to each other in the race with only a small gap left - this to me suggests that when the bearings are loose, the number of bearings should be sufficient to virtually fill the race?"

That would be my view too. You'll know if you have two many as they won't seat on the race properly as there won't be room.

 

[gwhite]

When using loose ball- bearings (always to be preferred in my opinion as they spread the load better) there will always be more then those found in the retaining clip. Pack in the grease and then fill with the loose ball bearings until the space is full. Now remove one ball bearing and assemble.
I know that cages are convenient but after one ruptured and ruined my Record BB I try to avoid them.

I buy my ball-bearings here and even the top quality ones are not too expensive.
http://simplybearings.co.uk/shop/ball_bearings.php?gclid=CIDB-_SRxakCFYJO4QodY0BNEQ