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Ceramic or not
#1
i have a pair of easton EA90 SLX's on stripping my rear wheel recently i discovered allot of play in the freehub body so i dismantled said body only to discover that the inside bearings had disintegrated and the outside bearings also had broken balls in. the cheaper option was to replace the bearings with standard steel ones at £8 each from easton rather than their ceramic equivalent at £25 each!

i have searched on line for cheaper steel bearings 15x26x7 found some half the price but is the price relevant to quality?

is performance going to be greatly affected?

and more importantly i thought ceramics were the bees knees?
[color=#1E90FF][align=center][size=large][font=Impact]Neil Aldridge aka mountain man
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#2
Whoa! I just looked at the price of your wheels before making a recommendation and I am at loss for words.

Normally I would say just replace them with steel ball bearings from a hardware store but . . . those wheels are pricey.

I think I would try and figure out why they "disintegrated" in the first place before moving forward. BTW, hardware store ball bearings are usually around a dollar/euro a piece or less, and should last a long time under normal circumstances.

Steve
Junkyard Tools rescued from the junkyard!
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#3
Regarding the disintegration of the bearings, did you over torque or someone else over torque the wheel when the hub was last maintained? Although ceramic is harder than steel, its also more brittle, under compression it will "disintegrate" whereas steel bearings would deform. Even a small over torque could lead to much higher wear on the bearings.

More exotic materials used in bikes typically have less tolerances so when using such things, carbon fibre, ceramic bearings etc. It becomes more important to ensure you maintain it correctly, ensure the torque used is correct, materials and processes etc.
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#4
i have a sneaking suspicion that the disintegrated ceramic bearings may have been caused when i hit a pot hole about six months ago. i had to replace the rim, i checked the hub bearings and they were fine but i guess its possible that the free hub bearings may have been damaged but as the wheel hub were ok i didn't check.
perhaps one or two were damaged and over time the others followed?
[color=#1E90FF][align=center][size=large][font=Impact]Neil Aldridge aka mountain man
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#5
I looked at the website for the wheels (http://www.eastoncycling.com/road/assets/?title=r4-rear&subtitle=bearing-removal) and it seems the bearing is a sealed unit with all the ball bearings in a sleeve, so £25 for each side of the wheel, seems acceptable considering the wheelset is so expensive.
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#6
You could also try some industrial bearing suppliers, none of the "cartridge" type bearings are actually made by cycle component manufacturers, instead the components are made to use available industrial bearings.

Try some of these:
http://www.bocabearings.com/default.aspx
http://www.bearing-king.co.uk/
http://simplybearings.co.uk/shop/
http://www.bearingboys.co.uk/

You'll find that ceramic bearings are expensive.
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#7
(07-21-2010, 01:19 PM)xerxes Wrote:  . . . You'll find that ceramic bearings are expensive.

Yup, I think this is an example of "over engineering" a product very prevalent today. Meaning that the old tried and true steel counterpart is actually more reliable and less expensive. Smile

It seems to me, the fact that Easton offers the steel version indicates they are aware of this problem.

Steve
Junkyard Tools rescued from the junkyard!
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#8
Yes 10-4 to xeroxes post re going to a bearing supply house and getting a set of steel bearings.
I have replaced bearings on my motorcycle that way . Except for the few bearings that are proprietary and special order.

You do have the size, 15X26X7 thats all you need. May be a good idea not to get sealed bearings so you can service (grease) them, if there is a external seal in the hub. Were your bearings pressed in? Can you get the outer races out without heating the hub or a press? You can make a press using a large c-clamp and some sockets. Although with the cost of these wheels it may not be a good idea as your first project. If its a caged bearings with bearings visible ignore the previous info.Photo would be good.

Get West European made bearings or Japanese.

As KC says on the older cone and race bikes you can replace caged bearings with loose bearings.


Did not know there were any hippies left. Ole hippy me. :-)))
Never Give Up!!!
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#9
I agree guys, not too crazy about having my coffee cup in my wheels. Tongue
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
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#10
the ceramic used is not the same as your coffee cup and yes i have sourced some steel ones from a uk supplier at a fraction of the cost, still extremely disappointed, replacing these with steel ones makes the ceramic ones in the hub totally pointless. i will not replace those but wait till i am feeling a bit more flush and buy the ceramics then
[color=#1E90FF][align=center][size=large][font=Impact]Neil Aldridge aka mountain man
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#11
Ok I will agree it is a different substance then my coffee cup. Maybe they are as strong as steel?! If one has a wheel with them inside the hub by all means stick with them. If they make bamboo bikes I am sure that bamboo, plastic, or ceramic wheels are the next generation. Not trying to make it sound like they "suck" or anything just I feel that material meant for other purposes should stay that way. Too dam dangerous as what is gonna happen when this happens..... (pictures below). You will noticed these are steel. Yes the steel ones break up too and can cause a lot of damage. I was going to save these pictures for a different post but this one is a good one. What does anyone think that will happen when the ceramics get to this point? I think they will disintegrate into dust and particles. The reason this one failed is because there was lack of new grease in the hub and probably manufacturer failure. Reason why I stress this is because I really would not like to see anyone get hurt.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
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#12
(07-27-2010, 05:59 PM)happyhippy Wrote:  the ceramic used is not the same as your coffee cup and yes i have sourced some steel ones from a uk supplier at a fraction of the cost, still extremely disappointed, replacing these with steel ones makes the ceramic ones in the hub totally pointless. i will not replace those but wait till i am feeling a bit more flush and buy the ceramics then

Well I think Bill and the rest of us were just honestly answering your question of whether to use "ceramic or not." But it now seems you didn't REALLY want to hear the answers in the first place, . . . as in "still extremely disappointed . . . (and) pointless . . . (and) buy the ceramics then."

But then maybe you were just trying to impress us all in the first place. Sorry we're not impressed.

Steve
Junkyard Tools rescued from the junkyard!
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#13
i did not come on here to try and impress anyone i came for advise in case any of you had used ceramic bearings, evidently not. and seeing as you have exhausted your knowledge or not on the subject i will bid you good bye.

thanks
[color=#1E90FF][align=center][size=large][font=Impact]Neil Aldridge aka mountain man
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#14
Joining this thread a little late, but I thought as a Mechanical Design Engineering; I could contribute some useful information about ball bearing materials.

Why ceramic? well on bicycles, weight but mostly marketing - I'd say 1% weight, 99% marketing. Ceramic balls are used in high speed (10,000 rpm and up) very high precision applications, with very careful match of thermal expansion coefficients (CTE). They must be properly (and usually very highly) preloaded; and must always be under compression. Impact loading which results in a loss of compression will destroy the ceramic balls almost instantly. Ceramic expands less than steel - and much much less than aluminum with increasing temperature. As alluded to above, they are not very good for low speed applications (all bicycle applications are low speed). If you are professional road racer, and your mechanic adjusts the bearing preload every day based on the expected ambient temperature - they are okay, and may be worth the weight reduction. If not, they will not last very long. The pro does not care, as they will be replaced at least every week.

Steel is great for bearings; 52100 is the most common bearing steel, it is very hard and very tough. Not as hard as ceramic, but much tougher. It will handle shock loads quite well. 52100 needs to be well lubricated to keep out moisture as well as to function properly as a bearing. 52100 will rust. 440C (and some proprietary cousins) is the most common stainless steel bearing material. It has much better corrosion resistance than 52100, but under extreme environments, it too will rust. 440C is not as hard as 52100, and has similar toughness. Steel bearings are more forgiving of the thermal expansion mis-matches than ceramic.

As others have suggested, the bearing should be replaced every time you take them out. Separate balls are very inexpensive, even at the LBS.

For my the products I design, I have used and would use again NMB, NSK and SKF bearings. These are all ball bearing assemblies. For the vast majority of applications (including bicycles), even so called "cheap" Chinese bearings are more than adequate if they are properly lubricated. For non-competitive riding, an automotive wheel bearing grease will keep your bicycle wheel bearings happy for thousands of miles. I suggest solvent (70% isopropyl alcohol is fine) cleaning the balls, raceways, cones, etc, drying then immediately apply the grease to all the metal surfaces inside the bearing system. Use nitrile gloves - your finger oils are bad for bearings.
Nigel
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#15
(09-27-2010, 07:59 AM)nfmisso Wrote:  Why ceramic? well on bicycles, weight but mostly marketing - I'd say 1% weight, 99% marketing.

Never thought they were marketed for the 1% weight. Thought it was for a lot less friction? At least on a wheel with only the weight of the wheel on the bearing?
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#16
(12-01-2014, 12:25 AM)rayms Wrote:  
(09-27-2010, 07:59 AM)nfmisso Wrote:  Why ceramic? well on bicycles, weight but mostly marketing - I'd say 1% weight, 99% marketing.

Never thought they were marketed for the 1% weight. Thought it was for a lot less friction? At least on a wheel with only the weight of the wheel on the bearing?

no difference in friction - they are rolling element bearings.
Nigel
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#17
(12-01-2014, 04:20 AM)nfmisso Wrote:  
(12-01-2014, 12:25 AM)rayms Wrote:  
(09-27-2010, 07:59 AM)nfmisso Wrote:  Why ceramic? well on bicycles, weight but mostly marketing - I'd say 1% weight, 99% marketing.

Never thought they were marketed for the 1% weight. Thought it was for a lot less friction? At least on a wheel with only the weight of the wheel on the bearing?

no difference in friction - they are rolling element bearings.

In a Youtube video, a regular hub spins for half a minute, a hybrid spins for one minute and the full ceramic spins for 6 minutes.
https://www.youtube.com/watch?v=q4Tc1U1Tg34
Even factoring in the person spun the ceramic ones harder, the ceramic one seem to have less friction. The full ceramic hub's friction is so low that when it spinning energy dies out you can see it spin in the opposite direction.
What part of the engineering, are we of little technical background, not following?
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#18
(12-05-2014, 12:52 AM)rayms Wrote:  In a Youtube video, a regular hub spins for half a minute, a hybrid spins for one minute and the full ceramic spins for 6 minutes.
https://www.youtube.com/watch?v=q4Tc1U1Tg34
Even factoring in the person spun the ceramic ones harder, the ceramic one seem to have less friction. The full ceramic hub's friction is so low that when it spinning energy dies out you can see it spin in the opposite direction.
What part of the engineering, are we of little technical background, not following?

A Youtube video is far from a reliable source of information. Anyone can rig things to get those results, or the opposite.

I (and many other people on this forum) can make a minor adjustment to a wheel which will result in the spin down time from a given rotational rate vary by two or more orders of magnitude.

Talk to the Engineers at any bearing company, and they can vary the drag torque of a cartridge bearing by 10X or more just by varying the amount of lubricant- and far more by changing the lubricants.

Further more, unloaded spin down tests have little correlation to bicycle wheel drag with rider on board.

And most importantly, wheel bearing drag is in an incredibly small part of the power required to move a bicycle.
Nigel
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#19
Nigel is spot on as usual, but I'll go further. The time one spends fretting over ceramic bearings, ordering and installing them will actually SLOW your speed, because rather than spending all that time for .001% advantage (no exaggeration) you could have been riding instead. Miles in the saddle trump pretty much everything else.

As for the original problem - it only takes ONE bad bearing to wreak havoc. Once it fractures the rest bear more stress, especially from impact and seizing due to the broken pieces. Judging steel bearings by the OP's experience in preference to that of millions of riders over more than a century is absurd.
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#20
Ought to be an interesting 2015. I just restored 2 bikes... One I did with new #25 Steel Ball Bearings (1969-70 Gitane Grand Sport Mixte)
and one I did with (Nearly) Free Mode 5 Ceramic Ball Bearings (1979-80 Peugeot U09).

I expect that next year I'll be very happy with both bikes, as neither had been serviced since manufacture.

Will I be able to tell a difference? I'll be happy to remember 2014 riding season, let alone be able to tell the difference that new Axle, cones, bearings and grease compared to a bent axle, out of round drilled cone, old bearings, and little or no grease.... and 5-6 months since our last ride...

I'm guessing as we both ride at the same time.... If we encounter infant mortality on one opposed to other type of bearings I'll post that.

I believe I spent $14 for Steel BB set for 2 Axles, Crank & Pedals, vs. $17 for the Front Axle (other Axle, Crank and Pedal Loose Ceramics were Free).. So I'm 'out' only $3 (They would have been totally free if I hadn't given him wrong size of front Axle bearings!)

Seeing that this will most probably be the only complete overhaul that is done to the bikes (Last one was 30-35 years ago!).... I guess we could all meet here 35 years from now and see how it works out........ Big Grin!
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