Do you feel the difference?

I am talking silicon nitride, not flowerpots. The jockeywheels sold by FSA go for $130 USD a pair. Ceramic bushings would have significantly increased friction over these. (Ceramic bushings aren't the same ceramic as these bearings). Who cares anyway, the jockey wheels of the new 105 and Ultegra are both G-Pulley wheels, I am pretty sure they are identical.

What makes you think the bushing in jockey wheels aren't SiN? SiN is highly comercalised and has extremely good properties for bearings and bushes.

SiN bearings are just a superior ceramic with good quality manufacturing. The basis of thier structure is similar though.

I agree a bearing is better than a bush.

OK then, but it is not the same refined and processed product as the SiN bearings, as they go through the costly treatment of whatever it was, bead blasting and something to get it round. If it were, the cost of jockey wheels would increase the price of a derailleur by hundreds of $

Getting off the topic here, could start a new thread (but won't)

Just because a bearing is made of SiN doesn't mean it’s of a high grade, just most bearings using this material are.

You can get ceramic balls from grade 7 through to grade 3 (smaller number tighter tolerances). You can find some very high quality stainless steel balls down to grade 7 (but they won't keep that finish as long). To get to the higher grade with SiN they have to do extra fine grinding and lapping to get the spherical tolerance and surface finish. Hence you can get a range.

I sell grade 5 balls, not seen a commercial source for grade 3 (special NASA/military order only?). Grade 5 balls are much rounder and have a better surface finish than the standard steel balls without pumping up the price tooooo high (which is a matter of opinion).

“Ceramic bearings” used for bikes are stainless steel inner and outer races with ceramic balls. They should be called hybrid ceramic, but it’s easier and better for the marketing to just call them “ceramic”. Full ceramics are stupidly expensive and likely only used in aero space, F1, and high temperature high speed industrial use.

The ABEC rating for full bearings is based on the tolerance of the races, not the balls, so you can get full steel bearings with the same ABEC rating as a hybrid ceramic. The hybrid ceramic would of course perform better (unless it had crappy cheap ceramic balls in it). The ceramic balls also remove a few of the failure mechanisms so the bearings last way way longer.

I’m guessing the ceramic bush in Shimano jockeys are fairly high grade. Think of the volumes they produce each year, the more you buy the less they cost. Ceramic bearings are very expensive at the moment as they are very new and super high tech. FSA also have no other major competitor so can demand a premium. Yes the prices will always be higher due to more production effort, but just look at how carbon fiber has come down over the years.

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Phill P said:

Getting off the topic here, could start a new thread (but won't)

Just because a bearing is made of SiN doesn't mean it’s of a high grade, just most bearings using this material are.

You can get ceramic balls from grade 7 through to grade 3 (smaller number tighter tolerances). You can find some very high quality stainless steel balls down to grade 7 (but they won't keep that finish as long). To get to the higher grade with SiN they have to do extra fine grinding and lapping to get the spherical tolerance and surface finish. Hence you can get a range.

I sell grade 5 balls, not seen a commercial source for grade 3 (special NASA/military order only?). Grade 5 balls are much rounder and have a better surface finish than the standard steel balls without pumping up the price tooooo high (which is a matter of opinion).

“Ceramic bearings” used for bikes are stainless steel inner and outer races with ceramic balls. They should be called hybrid ceramic, but it’s easier and better for the marketing to just call them “ceramic”. Full ceramics are stupidly expensive and likely only used in aero space, F1, and high temperature high speed industrial use.

The ABEC rating for full bearings is based on the tolerance of the races, not the balls, so you can get full steel bearings with the same ABEC rating as a hybrid ceramic. The hybrid ceramic would of course perform better (unless it had crappy cheap ceramic balls in it). The ceramic balls also remove a few of the failure mechanisms so the bearings last way way longer.

I’m guessing the ceramic bush in Shimano jockeys are fairly high grade. Think of the volumes they produce each year, the more you buy the less they cost. Ceramic bearings are very expensive at the moment as they are very new and super high tech. FSA also have no other major competitor so can demand a premium. Yes the prices will always be higher due to more production effort, but just look at how carbon fiber has come down over the years.

I know more than you think about hybrid ceramic bearings. Their main purpose is excellent heat resistance, and they also do not compress as much as steel under load. They have a much longer lifespan, come with stainless races (I know), are frightfully expensive and will outlast your bike. They are more about bearing life than performance benefits, though top level racers may see a miniscule performance increase of 4 watts max. This is for a cost of what could get up to $1500

bobbyOCR said:

I am nearly 100% sure Tiagra is not going to be 10 speed. 105 is the beginning of their 'racing' components.

FYI : 30 speed Tiagra is on the latest GIANT OCR2 bikes in stores now . They have a newly added gear indicator built into each lever aswell as the obvious upgrades in the cranks etc.

caferacerwanabe said:

FYI : 30 speed Tiagra is on the latest GIANT OCR2 bikes in stores now . They have a newly added gear indicator built into each lever aswell as the obvious upgrades in the cranks etc.

Thanks for that, but it still seems it is 9 speed. I haven't seen this anywhere before and it is interesting to note that it says 'octalink' as the BB, hollowtech II used shallow splines, not octalink. But, these are huge improvements and it also seems that the crank is a triple. Most likely ideal for touresrs, but Tiagra is still 9 speed and I don't think they have upgraded the fundamental parts which make it tiagra.

Tiagra: Fresh inspiration for road racing enthusiasts
11/09/2006
Nunspeet, The Netherlands

The new Tiagra group has been completely revamped, using technology from Shimano’s high end road racing groups. Tiagra offers excellent performance at an attractive price, for all those road racing and fitness enthusiasts that like to have fun on the road.

The Tiagra group features Double (52-39T), Triple (50-39-30T) and Compact (50-34T) front chainwheel options. These cranksets have been developed with an integrated bottom bracket with increased rigidity for an optimal power transfer. Tiagra cranksets feature Shimano’s HYPERDRIVE technology with shift ramps at the chainrings that offer super smooth front shifting, also under very high load.

Only one Dual Control Lever specification is needed for Double, Triple and Compact. These shifters feature an integrated optical gear display that’s highly visible right in front of your eyes.

Furthermore, they have been developed with a reach adjust possibility for riders with small hands. The lever can be adjusted closer to the handlebar by using shims in the bracket of the shifter. They will be available in two sizes (for 4 and 8 degrees adjustment) to ensure a perfect set-up depending on hand size and personal preferences.

Tiagra offers 9-speed cassette sprockets and a rear derailleur with wide link design that is also compatible with the compact crank. Two types of front derailleurs will be available: one for Double and Compact and the other for the Triple version. They also feature a wide link design for better power transfer that results in improved shifting performance.

The Dual pivot brakes will be provided with adjustable brake shoes and the hubs have been developed with an internal grease keeping system to improve durability. The hubs will be available in 32 and 36 spoke hole versions.

I C&P the above from Shimano Europe.....says 9 speed for Tiagra

bobbyOCR said:

I know more than you think about hybrid ceramic bearings. Their main purpose is excellent heat resistance, and they also do not compress as much as steel under load. They have a much longer lifespan, come with stainless races (I know), are frightfully expensive and will outlast your bike. They are more about bearing life than performance benefits, though top level racers may see a miniscule performance increase of 4 watts max. This is for a cost of what could get up to $1500

Yes excellent with heat
Yes compress less than steel (therefore less energy absorbed, just like high pressure tires)
Yes last much longer
Yes and no expensive, very FSA expensive, zipp very expensive, stuff I sell less than half the cost.
Performance increase can be felt, yes only a little but every little counts. A least it helps in every situation (fast/slow, flat/uphill), not just up hill when a lighter bike has a similar small effect. Plus they get the life span as well.

Some think the cost (around $100AUD or less depending on your wheels) is worth it, and I'm getitng good feedback. If you don't think its worth it then keep you money and save up for a light weight stem or saddle.

Hybrid bearings were created to prevent arcing in certain electric motor applications. Be careful what you're buying.

Also, sometimes people get enthusiastic about some new technology and make fanciful claims for what it's supposed to do, but there is no way those things have infinite life. their high quality may extend service life but their increased hardness loads the races more.

Phill P said:

Yes excellent with heat
Yes compress less than steel (therefore less energy absorbed, just like high pressure tires)
Yes last much longer
Yes and no expensive, very FSA expensive, zipp very expensive, stuff I sell less than half the cost.
Performance increase can be felt, yes only a little but every little counts. A least it helps in every situation (fast/slow, flat/uphill), not just up hill when a lighter bike has a similar small effect. Plus they get the life span as well.

Some think the cost (around $100AUD or less depending on your wheels) is worth it, and I'm getitng good feedback. If you don't think its worth it then keep you money and save up for a light weight stem or saddle.

I think it may be worth it but I am not sure at what point. If I have nothing else to upgrade I may turn to ceramic. I would rather pay for HC bearings than get a $500+ bar/stem out of carbon.

bobbyOCR said:

Thanks for that, but it still seems it is 9 speed. I haven't seen this anywhere before and it is interesting to note that it says 'octalink' as the BB, hollowtech II used shallow splines, not octalink. But, these are huge improvements and it also seems that the crank is a triple. Most likely ideal for touresrs, but Tiagra is still 9 speed and I don't think they have upgraded the fundamental parts which make it tiagra.

Apologies !!! yes major revamp but not 10speed!!! but the crank area is the major improvement.

For what its worth in this thread: Some of the biggest differences in shifting performance are not based on the group, but on the cables and how tightly the bends were made in them. Higher quality cables and housings stretch less and make for more-precise and robust adjustments. Even Dura Ace sucks with crappy cable running. I know, it was a problem I had with a bike I had. A different LBS showed me what was wrong, put new cables on my drivetrain and it shifted like it should have from the get go.

garage sale GT said:

Hybrid bearings were created to prevent arcing in certain electric motor applications. Be careful what you're buying.

Also, sometimes people get enthusiastic about some new technology and make fanciful claims for what it's supposed to do, but there is no way those things have infinite life. their high quality may extend service life but their increased hardness loads the races more.

You're right, hybrid ceramic bearings don't have an infinite life. Just like in standard steel bearings the inner race goes first as it has the smallest surface area so damage builds up fastest there.
The increased hardness of the ceramic balls is a negative for the point load on the race, but the ceramic balls remove a number of major failure contributors.

A major one is micro welding. When two metal surfaces contact each other under load you get what is called micro welding. The grease in the bearing helps prevent this with a thin film between parts but the grease degrades over time and contact becomes more common (good servicing helps here). Anyone who has warn out a set of cup and cone bearings and removed the steel balls and races will remember the gauged bumpy surface of the inner race and lumpy pitted surface of the balls from where the micro welding has occured when the elements have seperated again and small deposits are pulled from one surface and left on the other.
Ceramic does not micro weld, and holds its tolerances far longer than a steel ball due to the its hardness, so less micro welding and out of tolerance damage is done to the inner race.
Another issue is galvantic currents through the races and balls causing slow oxidation of surfaces. You may not see it as rust but the left over grease may have gone a little brown. SiN does not conduct electricity so the effects of galvanic currents are reduced.

I don't know exactly how much longer ceramic bearings last on bikes, but considering the failure modes removed, the balls and possibly the races too will last longer than most people would ever keep a hub.

Forgot to mention SiN is 60% lighter than steel (so you won't need those Ti bolts quite so soon!)

If you see the value then go for it, if not you'll probably still love riding your steel bearings. If you are about to replace the balls in your hubs then I suggest you give it some though. Full hybrid ceramic bearings in a large enough range to cover the major brands is beyond my means as a hobby ebay seller (I have to buy wholesale in large volume), but I have the required ball sizes for campy/fulcrum and shimano cup and cone hubs.

I better stop plugging something I sell before people start getting upset....

Insight Driver said:

For what its worth in this thread: Some of the biggest differences in shifting performance are not based on the group, but on the cables and how tightly the bends were made in them. Higher quality cables and housings stretch less and make for more-precise and robust adjustments. Even Dura Ace sucks with crappy cable running. I know, it was a problem I had with a bike I had. A different LBS showed me what was wrong, put new cables on my drivetrain and it shifted like it should have from the get go.

I cannot believe none of us thought of that, good posting 😉

Insight Driver said:

For what its worth in this thread: Some of the biggest differences in shifting performance are not based on the group, but on the cables and how tightly the bends were made in them. Higher quality cables and housings stretch less and make for more-precise and robust adjustments. Even Dura Ace sucks with crappy cable running. I know, it was a problem I had with a bike I had. A different LBS showed me what was wrong, put new cables on my drivetrain and it shifted like it should have from the get go.

Good point.

Phill P said:

You're right, hybrid ceramic bearings don't have an infinite life. Just like in standard steel bearings the inner race goes first as it has the smallest surface area so damage builds up fastest there.
The increased hardness of the ceramic balls is a negative for the point load on the race, but the ceramic balls remove a number of major failure contributors.

A major one is micro welding. When two metal surfaces contact each other under load you get what is called micro welding. The grease in the bearing helps prevent this with a thin film between parts but the grease degrades over time and contact becomes more common (good servicing helps here). Anyone who has warn out a set of cup and cone bearings and removed the steel balls and races will remember the gauged bumpy surface of the inner race and lumpy pitted surface of the balls from where the micro welding has occured when the elements have seperated again and small deposits are pulled from one surface and left on the other.
Ceramic does not micro weld, and holds its tolerances far longer than a steel ball due to the its hardness, so less micro welding and out of tolerance damage is done to the inner race.
Another issue is galvantic currents through the races and balls causing slow oxidation of surfaces. You may not see it as rust but the left over grease may have gone a little brown. SiN does not conduct electricity so the effects of galvanic currents are reduced.

I don't know exactly how much longer ceramic bearings last on bikes, but considering the failure modes removed, the balls and possibly the races too will last longer than most people would ever keep a hub.

Forgot to mention SiN is 60% lighter than steel (so you won't need those Ti bolts quite so soon!)

If you see the value then go for it, if not you'll probably still love riding your steel bearings. If you are about to replace the balls in your hubs then I suggest you give it some though. Full hybrid ceramic bearings in a large enough range to cover the major brands is beyond my means as a hobby ebay seller (I have to buy wholesale in large volume), but I have the required ball sizes for campy/fulcrum and shimano cup and cone hubs.

I better stop plugging something I sell before people start getting upset....

I won't be the one upset. You have an interesting item and you offer it. Sounds fine. You are straight up about yourself and what you have. If however you start riding over 200 miles at over 22 mph average and get the bearings from martians...oh lets not go there again, sorry!

mrklein said:

I won't be the one upset. You have an interesting item and you offer it. Sounds fine. You are straight up about yourself and what you have. If however you start riding over 200 miles at over 22 mph average and get the bearings from martians...oh lets not go there again, sorry!

DON'T START. just don't. funny though 😄

I'll take a used 2yr old dura ace rear derailler over comparably used 105... I believe that the dura ace shifts smoother much longer... I can't afford new very often... i will bet dollars to donuts that the bushings are harder/more precise, and tolerances are closer in the DA...

Shimano Tech?

Phill P said:

You're right, hybrid ceramic bearings don't have an infinite life. Just like in standard steel bearings the inner race goes first as it has the smallest surface area so damage builds up fastest there.
The increased hardness of the ceramic balls is a negative for the point load on the race, but the ceramic balls remove a number of major failure contributors.

A major one is micro welding. When two metal surfaces contact each other under load you get what is called micro welding. The grease in the bearing helps prevent this with a thin film between parts but the grease degrades over time and contact becomes more common (good servicing helps here). Anyone who has warn out a set of cup and cone bearings and removed the steel balls and races will remember the gauged bumpy surface of the inner race and lumpy pitted surface of the balls from where the micro welding has occured when the elements have seperated again and small deposits are pulled from one surface and left on the other.
Ceramic does not micro weld, and holds its tolerances far longer than a steel ball due to the its hardness, so less micro welding and out of tolerance damage is done to the inner race.
Another issue is galvantic currents through the races and balls causing slow oxidation of surfaces. You may not see it as rust but the left over grease may have gone a little brown. SiN does not conduct electricity so the effects of galvanic currents are reduced.

I don't know exactly how much longer ceramic bearings last on bikes, but considering the failure modes removed, the balls and possibly the races too will last longer than most people would ever keep a hub.

Pitting is a fatigue failure, not "micro welds".

Reducing the number of failure modes does not increase part life because it only takes one failure mode for a part to fail.

Your cones are more likely to pit with Si3N4 balls because they are harder, indent the races more, and cause more fatigue.

I would be surprised to learn that a factory wheelset from a reputable maker came with ceramic balls which were the same size as a comparable steel bearing.