Ball bearings

[brad890]

Those are good hubs. They have proper seals and other than a poorly aimed Karcher, nothing should get past the seals. They are worth servicing and looking after.

 

New hubs translate to new wheels and I won't recommend you do that until you've completely given up on those hubs.

 

I can send you some balls, contact me offline.

 

Stay way from any pressure spray cleaning method. Just because they use these things at races it doesn't mean it's a good idea. It's a disservice arming the local population with Karchers and presenting it as a benefit at the race. Wash your own bike using a bucket and brush.

 

ok cool, I'll send you a PM thank you very much for the help

 

Brad

[Johan Bornman]

yeah i know that, and i make sure the hubs are always running sooth and are greased, i do it myself its a 5-10min job per wheel and is easy peasy. just the ball bearings themselves dont seem to last, its almost like they flake apart like a jaw breaker with its different layers and turn square per say

 

The Irish have improved the square bearing - they now have a triangular one, the benefit being one less bump.

 

The flaking you see is the hard layer coming off the bearing. It is typical of a badly adjusted cone.

 

Cones should be adjusted so that the axle has a just-perceptable play when the wheel is on the bench. Put the wheel in the bike and tighted the QR and the play should be gone. Yet, the wheel should still settle at the heaviest point each time.

 

It is quite difficult to get right and one of the things my students struggle most with.

 

If the bearings don't have enough preload, only the bottom ball takes the brunt of the bike's load. If they are too tight, they squeeze out the lubrication boundary layer and slide steel on steel.

 

Bearing balls don't rotate perfectly on their races like train wheels do. Because the outer race is longer than the inner one, the bearings half-roll, half-slide and pressing the lubrication out is a bad idea.

 

Perfectly-adjusted bearings last a very long time - thousands of kilometers.

 

I reckon 80% of bike shops don't know how to adjust cones.

[brad890]

The Irish have improved the square bearing - they now have a triangular one, the benefit being one less bump.

 

The flaking you see is the hard layer coming off the bearing. It is typical of a badly adjusted cone.

 

Cones should be adjusted so that the axle has a just-perceptable play when the wheel is on the bench. Put the wheel in the bike and tighted the QR and the play should be gone. Yet, the wheel should still settle at the heaviest point each time.

 

It is quite difficult to get right and one of the things my students struggle most with.

 

If the bearings don't have enough preload, only the bottom ball takes the brunt of the bike's load. If they are too tight, they squeeze out the lubrication boundary layer and slide steel on steel.

 

Bearing balls don't rotate perfectly on their races like train wheels do. Because the outer race is longer than the inner one, the bearings half-roll, half-slide and pressing the lubrication out is a bad idea.

 

Perfectly-adjusted bearings last a very long time - thousands of kilometers.

 

I reckon 80% of bike shops don't know how to adjust cones.

 

hmm then i might be over tightening them then, i always assumed one wanted no play, as play is what lead to ball bearing damage (from what i understood), i always tightened to the extent where they had no play, but rolled smoothly without resistance, didnt know you need a slight bit of play before putting them back on the bike and no play after.

[dirtrider]

WTF , the bottom ball ? If you got a bottom ball you are doing it wrong . There is NO part in a MTB that warrant the use of a high grade bearing . Cheap chinese **** will do just fine .

[Big H*]

hmm then i might be over tightening them then, i always assumed one wanted no play, as play is what lead to ball bearing damage (from what i understood), i always tightened to the extent where they had no play, but rolled smoothly without resistance, didnt know you need a slight bit of play before putting them back on the bike and no play after.

 

Maybe a twenty naainer and full suspension can solve your square balls?

[David Marshall]

WTF , the bottom ball ? If you got a bottom ball you are doing it wrong . There is NO part in a MTB that warrant the use of a high grade bearing . Cheap chinese **** will do just fine .

 

 

Can't agree. I will drive a long way to get good bearings for any application before I use Chinese. Same goes for tools and just about everything else.