New sealed cartridges bearings not turning

[rockyraccoon]

Hi all,

I've just bought some ZEN Deep Groove Ball Bearing (cartridges double sealed) for my wheels and freehub. They are Standard bearings exactly the same number/model/size as my old ones.

They are brand new and a bit greased on outside.

The bearings feel a bit stiff when trying to turn it on my fingers.

Are they difficult to turn because they're new or they have too much grease inside the seals?

Would it be OK to install / use them? Will they loose up more after a few dozen miles and run more free? Or they are not good for cycling?

 

[raleighnut]

Grease won't stop em turning, the seals may though. Sounds like they're cheap bearings though if they're stiff, does it say where they are made.

 

[Yellow Saddle]

Once they are in the wheel you won't even notice they are slightly stiff. Bearings are filled with grease (between 25% and 80% of vacant capacity) and have contact seals. By definition there has to be friction. Those bearings in things like fidget spinners have no grease or seals.

 

[rockyraccoon]

I don't know where they are made. They are ZEN that's a German company but I assume the factory is in China as most things are manufactured nowadays

The old bearings would spin freely after cleaning, with double seals in and without any grease but they wouldn't last too long if used dry.

For bicycle, I always thought bearings are bearings, some will last longer others will need more maintenance regrease. The speed they turn is negligible on the bike and I probably never notice it.

I'm just wondering if anyone has ever used standard low cost bearings which are a bit stiff when turning by hand but once installed it was fine after and got the expected results.

I don't want to use them if it's not going to work

 

[Ticktockmy]

Depending on what use bearings have been designed for depends on which grease is used, Sealed bearings are sealed for life, or should be, mind you can tease the seals out and repack them but that not good practice. ZEN bearings are on pare with FAG and SKF.. Your bearings should be OK, and once fitted and been used for a few miles should spin freely.

 

[Levo-Lon]

Sealed bearings have metal covers.
The semi sealed have the flip out one's that can be cleaned. Re-greased

As said they will be fine when in use

 

[Yellow Saddle]

Sealed bearings have metal covers.
The semi sealed have the flip out one's that can be cleaned. Re-greased

As said they will be fine when in use

Not quite. Those metal covers are not seals, they're shields. They are contact-less and not intended for use where there is water. They're best for applications like shafts on machines such as bench grinders, where the shield will prevent particles from entering but not moisture. These shields are indicated by the Z code. I.e. a 6082 ZZ bearing has two shields, one on each side.
An R code indicates rubber seals, 6082 RS2 would have a rubber seal on each side. If there is only one code, then the one side is open. 6082Z would just have one shield. An absense of code is completely seal-less and intended for running in oil baths.

 

[gbb]

I don't know where they are made. They are ZEN that's a German company but I assume the factory is in China as most things are manufactured nowadays

The old bearings would spin freely after cleaning, with double seals in and without any grease but they wouldn't last too long if used dry.

For bicycle, I always thought bearings are bearings, some will last longer others will need more maintenance regrease. The speed they turn is negligible on the bike and I probably never notice it.

I'm just wondering if anyone has ever used standard low cost bearings which are a bit stiff when turning by hand but once installed it was fine after and got the expected results.

I don't want to use them if it's not going to work

When i got my Fulcrums, i immediately noticed a 'resistance' when freewheeling compared to my former wheelset that had done plenty of miles. I felt the new wheels would lose speed quite quickly and roll to a stop way before i felt i did previously.
IIRC the bearings in the Fulcrums were unbranded (i still have them in a bag, not that its relevent )
No doubt if i'd run them for a while they'd have freed up but impatience got the better of me and i brought some low friction sealed SKF jobbies. The difference was instant, but you're probably comparing £1 unbranded bearings with what were then maybe £6 SKF bearings.

Even with new standard SKF bearings, you can feel the resistance when turning them by hand, thats quite normal. It will probably free up with running.
With low friction sealed bearings you can feel the difference, they will run freer by hand straight from the box.
Whether that truly makes that much difference in the long term is debatable or perhaps negligable. In essense what i probably did was pay extra so i didnt have to wait for the originals to free up....but i'm ok with that, plus i now have higher quality bearings fitted.

BTW, there is a misconception that sealed bearings are maintenance free. They are in a sense but you can opt to maintain them. An example is my Veloce BB, i could feel a slight knock and roughness building up. They are of course sealed bearings but that doesnt stop you whipping the cups out, flipping one seal off the bearing, cleaning it out, regreasing and refitting the cup. This done, my BB is smooth again, no knock.
The same applies to any sealed bearings.

 

[rockyraccoon]

Ok, great info. I'm going for it. I will fit them in and see what happens. Thanks for the assurance

 

[gbb]

Bear in mind Rocky, my Fulcrums, maybe your wheels (I'm not talking about the freehub mind) and many others, only have a rubber seal on one side, to the inside of the hub where theres no ingress of water, grit etc.
If you flip out one of the seals on your bearings, it will reduce the friction.

 

[gbb]

Before you fit them Rocky, if you've a mind to, carefully flip out one of the seals and see if the individual balls are held in a (probably) a plastic cage to separate them from each other.
If they're not, the bearings really are cheap and IMO nasty.

Forgive me if I'm teaching you to suck eggs, when you fit your new ones, DON'T use the inner ring / race of the bearing to drive them in, you'll damage them. ALWAYS drive them in using the outer ring /race.

 

[Yellow Saddle]

Bear in mind Rocky, my Fulcrums, maybe your wheels (I'm not talking about the freehub mind) and many others, only have a rubber seal on one side, to the inside of the hub where theres no ingress of water, grit etc.
If you flip out one of the seals on your bearings, it will reduce the friction.

Don't do that. Just because Fulcrum and its parent company Campag does it, it doesn't mean it is a good idea. It is a very bad idea with no engineering basis at all. I'll explain as soon as I've fished out photos from my archive to illustrate. Perhaps I have even posted details before which will save me from regurgitating it.

 

[Ajax Bay]

I've just bought some ZEN Deep Groove Ball Bearing (cartridges double sealed) for my wheels and freehub.

https://www.cyclechat.net/threads/f...-bearings-made-of-butter.217201/#post-4768715

 

[Yellow Saddle]

1. I can't seem to find the post where I wrote about seals.
   
   It is important that a deep groove bearing that doesn't run in an oil bath, have two seals/shields, one on each side. Seals perform two functions, they (sort of) keep water/dirt out and they help recirculate the grease.
   
   Imagine a bowling ball rolling down the bowling alley gutter. The gutter is full of water. In front of the ball, there's a pressure wave. Behind the ball there's a rooster tail and eddy. On either side of the ball, the water splashes sideways, out of the groove. Send enough balls down that gutter and it runs empty. Build a short wall down either side of the gutter and the water splashes back. That's exactly what happens in a deep groove bearing. The seals help push grease, displaced by the ball, back onto the track, into the next ball's path.
   
   With one seal missing, the grease is soon displaced, leaving the balls dry. Such a bearing will spin much easier, but its life is shortened.
   
   This photo illustrates the phenomenum nicely. These two came out of a Campag wheel, one of the cheaper Campags which use cartridge bearings.
   
   If you look at the displaced grease, you'll see that it is pushed out. It bulges out. there's a thin shear line around the circumference in the grease and the balls are essentially dry. There is no mechanism to return the grease to the balls. It is a silly idea brought to you by the nation that invented the Alfa Romeo. Yes, those wheels spin marginally better than those with a full compliment of seals, but it is a false "fix".
   
   Seals do lose some grease and they should. It is explained here:
   
   https://www.cyclechat.net/threads/grease-leaving-hub.195376/#post-4135642
   
   and here.
   
   https://www.cyclechat.net/threads/question-about-dodgy-wheel-bearings.175056/#post-3550451
   
   
   
   
   
   
   
   

 

[gbb]

In a way i agree YS, it is bad practice. BUT....
Fulcrum and perhaps others supply their wheels like that, one seal removed. I replicated that when I fitted my SKFs and tbf, several thousand miles later I had the hubs apart and there was very very little grease displacement, it was all still pretty much as it should be. That said, in certain conditions perhaps it can be much worse,.I
I can guess why Fulcrums do this, to reduce drag, there's no other reason I can think of to warrant removing a seal.

It's (IMHO) like many things, a compromise. Yes there's a negative side to the practice, but there's a positive one as well. You pays yer money...so's to speak....even if the gains are small...even miniscule. But then, its just a bearing, its something that's quite cheap and usually easy to replace.

I'd say if you want longevity and to almost guarantee as longer bearing life as possible, yes, leave both seals in.
If you want a marginal gain and don't mind the fact that at best your bearings may not last as long...take one seal out. (If that's how your original manufacturer supplied your wheel bearings)