What's the relevance of a pitted hub cone/cup?

Ugo51

Retro Guru
Hi guys,

I was servicing some old Maillard hubs and they rear one has some slight pitting in the nds cup.
Nothing major, just a speck where the surface is no longer smooth. Is it something to shrug off, or once pitted the cup will degrade quickly?
 
Re:

It'll only get worse over time. It's normal wear and tear.
It sounds like your hub should be OK though, if it turns smoothly with the bearings and grease in there then it'll probably be good for a few thousand more miles.
 
Thanks.
Probably not worth to keep to build a new wheel then. A few thousand miles go by very quickly :)
 
Re:

I used to really fret about this but am quite relaxed now. Pitting is where the case hardened layer has eroded. do inspect with a magnifying glass to see what’s happening, and I do a very careful reset of the cups. A couple of things.

Don’t overfill with grease - there’s a discussion that excess grease bridging the inside and outside of the hub does recirculate around the seals dragging dirt into the bearing.

Make sure all seals are good. Replace if not, if they are available. I scrounge come seals from spare axles if they’ve gone missing.

Do use high quality grease - eg white Finish Line.

Do use expensive balls - eg campag. They select their balls, other companies do not.

Set the bearings so that the tightest part of the rotation is not too tight. It’s too tight if - when spun whilst being held by two hands the wheel slows at a particular point. It should rotate until a point where it reverses and the valve (when you have tube and tyre on) settles at the lowest point.

Weirdly, one of the world’s most experienced wheel builders told me to set bearings very very slightly loose, and they then tighten in the frame when you do up the QR. And they do. Still don’t quite understand why locknuts and cones move at all on the threads, but they do tighten up, just a weeny bit.

And I’ve got wheels which I thought were entirely screwed, which have gone on for over a decade.....
 
Buy grade 10 loose balls from a bearing supplier, those crappy things in packets are grade 100 down to 1000.
 
Re: Re:

2manyoranges":2dryvlz5 said:
I used to really fret about this but am quite relaxed now. Pitting is where the case hardened layer has eroded. do inspect with a magnifying glass to see what’s happening, and I do a very careful reset of the cups. A couple of things.

Don’t overfill with grease - there’s a discussion that excess grease bridging the inside and outside of the hub does recirculate around the seals dragging dirt into the bearing.

Make sure all seals are good. Replace if not, if they are available. I scrounge come seals from spare axles if they’ve gone missing.

Do use high quality grease - eg white Finish Line.

Do use expensive balls - eg campag. They select their balls, other companies do not.

Set the bearings so that the tightest part of the rotation is not too tight. It’s too tight if - when spun whilst being held by two hands the wheel slows at a particular point. It should rotate until a point where it reverses and the valve (when you have tube and tyre on) settles at the lowest point.

Weirdly, one of the world’s most experienced wheel builders told me to set bearings very very slightly loose, and they then tighten in the frame when you do up the QR. And they do. Still don’t quite understand why locknuts and cones move at all on the threads, but they do tighten up, just a weeny bit.

And I’ve got wheels which I thought were entirely screwed, which have gone on for over a decade.....

Thanks. Useful tips.
I also seem to notice that when I use too much grease, the wheels drag a little bit and they don't run as well as they should.
 
mdvineng":1m1p491t said:
Buy grade 10 loose balls from a bearing supplier, those crappy things in packets are grade 100 down to 1000.

I didn't even know there were grades for ball bearings! I'll keep that in mind for sure.
 
Re:

Few things I've got to add having also been servicing 4 maillard hubs over the weekend. They don't turn that smooth even with brand new cones installed, so keep that in mind, it is better to adjust for no play (when tightened into the frame) and not worry too much about how smooth they are.
The best tip I've been given about setting bearing tension is to turn the bike over and put one side of the axle in the dropout and have the other side free in the air (works best on a bike with thicker dropouts so use a modern bike or a mtb if possible as old presses steel dropouts aren't that thick), then tighten the quick release so that it hold the axle tight against the dropout. This now allows you to adjust the bearings with the added tension of the quick release already accounted for, and has the added benefit of meaning the axle doesn't rotate as you make adjustments.
 
Re:

Interesting stuff, didn't realise there was that much to it :oops:

Greasing hubs, I would rather spend the day with my Mother in law :D
 
Re: Re:

widowmaker":1hynrklm said:
Greasing hubs, I would rather spend the day with my Mother in law :D

I couldn't agree more, it's why I get annoyed when someone asks about sealed cartridge bearings and 20 people descend on him like a pack of lions telling him that cup and cone bearings are the best and cartridge bearings result in your immediate death.
 
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