Ceramic Bearings II

Discuss light weight issues concerning road bikes & parts.
Paul_nl
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by Paul_nl

Last year there was a topic about ceramic bearings for hubs and BBs.

http://weightweenies.starbike.com/forum ... .php?t=595

But I can't find the answer for the topic starter.

- For 150 euro more I can buy mavic wheels with sfk ceramic (hybrid) bearings here at a LBS. Is that worth the money? (1150 euro for cosmic carbones with skf ceramic bearings)

- Are bearings in a ksyrium SL from 2003 easy to replace? And what kind of bearings do I have to buy for them?

When I am correct: hybrid ceramic bearings do not have any weight advantage compared to normal bearings because the balls are made from steel but have an ceramic layer. The only advantage of ceramic bearings are durability? Because rollingresitance would only be an advantage on paper (a theoretically advantage)?

Full ceramic bearings do have a little weight advantage but are very very expensive?

brianwchan
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by brianwchan

I have heard people on here say that boca bearings is good, for ceramics. And they are relatively cheap. Check it out.

by Weenie


fdegrove
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by fdegrove

Hi,

For 150 euro more I can buy mavic wheels with sfk ceramic (hybrid) bearings here at a LBS. Is that worth the money? (1150 euro for cosmic carbones with skf ceramic bearings)


The company making these special bearings is SKF. Their customers for these bearings vary from avionics (Boeing, Airbus) to L'Aerospatiale, medical appliances, etc.....You get the picture...

Either way, ceramic ball bearings come in two main categories: full ceramic balls and housings and what is commonly refered to as the hybrid bearings: ceramic balls running in hardened steel bearing housings.

As an upgrade to an existing hub only the hybrid type is used, the ceramic balls decrease friction by about 90% (not always that much but still) and continuously hone the bearing reducing pitting in the process.
This is probably the upgrade you're talking about as offered by Math Salden in Holland.
Overhere (Belgium) we can buy the bearing balls as an upgrade for BBs and hubs. The distributor has the exclusive rights for SKF ceramic bearings as applied to bicycles for a couple of years so no need to search through other channels.

Whether that's worth the additional extra 150 Euro on top of the wheelset is open to debate and entirely up to the customer. The asking price given the materials and labour involved certainly isn't exorbitant.

However, I would only consider this if the wheelset is already of impecable pedigree and if the company doing the upgrade is willing to pick up the original manufacturer's warranty.

Besides that, yes, it should make for a noticeable improvement; anything that reduces friction should.

One caveat: never use lithium grease with this type of bearings as it will tend to offset the reduced friction, use PTFE loaded oil instead.
Full ceramic bearings within a ceramic housing don't even require any grease or oil to be present, friction is that low.

- Are bearings in a ksyrium SL from 2003 easy to replace? And what kind of bearings do I have to buy for them?


Once you know how it's not that hard to do but you need the tools and the correct parts. If it were my wheels I'd send them to a competent mechanic and be done with it.

When I am correct: hybrid ceramic bearings do not have any weight advantage compared to normal bearings because the balls are made from steel but have an ceramic layer.


Not correct. See the explanation above, the ceramic balls are made entirely out of silicium nitride. Ceramic housing could be made with just the cage made of ceramic, the housing only keeps the bearing assy together.

Full ceramic bearings do have a little weight advantage but are very very expensive?


Yes.
However you'll gain more from the reduced friction in everyday use then you would from losing say 500g weight off the bike.

Ciao, :wink:
Last edited by fdegrove on Mon May 09, 2005 10:42 pm, edited 1 time in total.
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tommy
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by tommy

I'm riding SKF ceramics and i do notice a difference. I'm using them in my mavic wheels. (ksyrium sl and cosmic carbone) I really feel a difference in the cosmics at high speeds. they run much smoother then the steel bearings and they create a "cool" sound probably because there is less grease in the bearing because of less friction.
i payed 35euro/bearing (you need 4 in mavic's) at my lbs.

I've just reasently replaced my steel bal bearings for ceramic ball's in my dura ace 7700 hubs. Didn't have the time to test these jet.
I'll post a reply when i have tested them.

Oswald
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by Oswald

fdegrove wrote:The distributor has the exclusive rights for SKF ceramic bearings as applied to bicycles for a couple of years so no need to search through other channels.


Your LBS can also order them from Codagex, the Mavic distributor.

Tommy, can you let me know how the DA hubs ride after the upgrade? I was also looking at upgrading them. I doubt it will make much difference, since the cones are still steel instead of ceramic.

Paul_nl
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by Paul_nl

fdegrove wrote:Hi,

The company making these special bearings is SKF. Their customers for these bearings vary from avionics (Boeing, Airbus) to L'Aerospatiale, medical appliances, etc.....You get the picture...

Either way, ceramic ball bearings come in two main categories: full ceramic balls and housings and what is commonly refered to as the hybrid bearings: ceramic balls running in hardened steel bearing housings.

As an upgrade to an existing hub only the hybrid type is used, the ceramic balls decrease friction by about 90% (not always that much but still) and continuously hone the bearing reducing pitting in the process.
This is probably the upgrade you're talking about as offered by Math Salden in Holland.
Overhere (Belgium) we can buy the bearing balls as an upgrade for BBs and hubs. The distributor has the exclusive rights for SKF ceramic bearings as applied to bicycles for a couple of years so no need to search through other channels.

However, I would only consider this if the wheelset is already of impecable pedigree and if the company doing the upgrade is willing to pick up the original manufacturer's warranty.

When I am correct: hybrid ceramic bearings do not have any weight advantage compared to normal bearings because the balls are made from steel but have an ceramic layer.


Not correct. See the explanation above, the ceramic balls are made entirely out of silicium nitride. Ceramic housing could be made with just the cage made of ceramic, the housing only keeps the bearing assy together.


So the hybrid balls are full ceramic only the housing is from steel? Hmm, I always thought that it was only a layer of ceramic around a bal of steel.

What is the internet address of the distributor that has the exclusive rights for SKF ceramic bearings? I could only find skf.be and skfsport.com

Ceramic bearings would that make the perfect winter hubs? For outdoor training on the salty roads?

fdegrove
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by fdegrove

Hi,

Your LBS can also order them from Codagex, the Mavic distributor.


Yes, by "other channels" I meant other than Codagex N.V./S.A.
I assume the same deal with SKF was struck by Codagex in the Netherlands.

In a nutshell, no need to search for any "bicycle typical" ceramic bearings made by SKF at the local hardware shop, they will have to go through the Codagex channel anyhow.

So the hybrid balls are full ceramic only the housing is from steel?


While bearing balls made out of a steel core and ceramic top coating do exist I do not think this is what is used here nowadays.
The term "hybrid bearing" is used to indicate that the ceramic ball is interfacing with a non-ceramic bearing cage, hence the hybrid nomer.
Normallly the easiest and most cost-effective upgrade path is to replace the steel balls in the bearing with ceramic ones.
Bearing tension should than be adjusted as well as lubrication to ensure a play free bearing assy.
Note also that it would be wise to recheck bearing play once the wheel is on the bike as the majority of skewers used exert so much compression that play is noticeably reduced.
Fixed compression skewers do exist and come highly recommended in my book....

Ceramic bearings would that make the perfect winter hubs? For outdoor training on the salty roads?


Ceramics don't rust as it can't bond with water but the steel housing still would.
The ceramic bearing however would hone the steel housing continuously through use thanks to it's lower friction and higher precision, this would remove rust and other micro-crud from the bearing housing making it last longer.
Depending on how well the hub is sealed it should in theory last longer than its regular counterpart under harsh weather conditions.

That aside, it would be interesting to see how low friction/low stiction drivetrain parts would improve both wear and tear and effeciency.
Der. pulleys are readily available using ceramics as are ceramic tipped chainrings and cogs but the entire system is still terribly primitive engineeringwise.
But that's another story.

Codagex's website can be found here:

http://www.codagex.com/pages/index.aspx

Check the "News" section where the SKF precision bearings are announced and further explained.
In Dutch and French only unfortunately.

Ciao, :wink:
Being a snob is an expensive hobby.

Paul_nl
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by Paul_nl

What I found from that website for everybody with a little english description:

SKF bearings for mavic wheels from 2000 - 2005 (pdf file)

How to install SKF bearings on mavic hubs (pdf file)

Info about mavic hubs (pdf file)

Dutch news message about mavic and SKF
When you put the text in babel fish and translate it from dutch to english you can understand what they are saying.


Codagex pricelist Select SKF for the bearings and find which bearing you need with the first pdf file

Some dutch words:
lager = bearing
naaf = hub
naven = hubs
achternaaf = rear hub
voornaaf = front hub
verwijder = remove

Paul_nl
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by Paul_nl

When I understand it correct you have to buy 5 bearings for most of the sets?
VL + VR + AL + AR + body

That would be around 5 x 35 euro = 175 euro

fdegrove
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by fdegrove

Hi,

When I understand it correct you have to buy 5 bearings for most of the sets?


I would have a hard time believing only 5 balls were used for a complete set of wheels....

Mavic Ksyriums probably use sealed ball-race type bearings but I wouldn't know for sure.
More common cup and cone bearings are much easier to service, just open it, count the number of balls and replace with the same number and diameter.
Check with Mavic, Codagex or your vendor, they should know what to order and how to fit in the new balls.
Without the technical datasheet for the Ksyrium SL anno 2003 it's bound to be a hit and miss affair....

Ciao, :wink:
Being a snob is an expensive hobby.

VVV
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by VVV

fdegrove wrote:Hi,

When I understand it correct you have to buy 5 bearings for most of the sets?


I would have a hard time believing only 5 balls were used for a complete set of wheels....

Mavic Ksyriums probably use sealed ball-race type bearings but I wouldn't know for sure.
More common cup and cone bearings are much easier to service, just open it, count the number of balls and replace with the same number and diameter.
Check with Mavic, Codagex or your vendor, they should know what to order and how to fit in the new balls.
Without the technical datasheet for the Ksyrium SL anno 2003 it's bound to be a hit and miss affair....

Ciao, :wink:


I believe he means 5 cartridges of bearings, becuase K's use cartridge bearings. 5 would be about right.....

Paul_nl
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by Paul_nl

Yes, I meant that according to the links I have posted.

For a 2005 cosmic carbone SL it should be 2 x product 608 and 3x product 60001. Then it's more expensiver to buy the 5 sets and do it myself than let Math Salden do it for 150 euro.

fdegrove
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by fdegrove

Hi,

Then it's more expensiver to buy the 5 sets and do it myself than let Math Salden do it for 150 euro.


Isn't that offer only valid when you buy your new wheels from them?

Ciao, :wink:
Being a snob is an expensive hobby.

Oswald
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by Oswald

fdegrove wrote:When I understand it correct you have to buy 5 bearings for most of the sets?

I would have a hard time believing only 5 balls were used for a complete set of wheels....


Mavic use cartridge bearings. Shimano use ball bearings. The ceramic ball bearings can only be ordered thru CDX in packs of 100. So for a Shimano wheelset, you would have to buy 200 balls because there are 2 different sizes.

by Weenie


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spytech
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by spytech

a little off topic. do the tune hubs come with hybrid ceramic bearings???

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