f4rrest

Not sure if you realize this, but cartridge bearings come with either both sides sealed (with a rubber gasket) or with only one side sealed. It's this seal that contributes much of the friction to spinning a bearing or wheel by hand.

Many of the "performance" bearings use cartridges with only a single side sealed, leaving the unsealed side facing internally, where it's less likely to get dirty anyhow.

It's quite possible that the ceramic bearing wheel was also using single sided bearings while the steel bearing wheel was not.

It's also possible that the wheels have preload settings, and they weren't set the same.

As others have said, ceramic bearings are not worth it on a bike.

CliffordK

I wonder if the old oil holes will come back with the hubs.

Outer sealed.
Inner open.
Sloshing of oil inside.

Once a year or so, pull the axle and clean with mineral spirits or one's water based cleaner of choice & replace oil.

Dirt penetration may be one of the causes of the demise of some sealed cartridges.

Doge

You can buy full ceramic - so white on the outside. They do very poorly with water and thus, if you have a pro mechanic - not a good idea.
My son says he notices. As he competes and uses in TTs - 1-2 sec helps. I think they are good for that.


Part 2:
I normal remove all inner seals. Ceramic or not.

exmechanic89

Not to be confrontational but how could anyone possibly verify they saved 1 or 2 seconds using ceramic bearings?

Personally, I think ceramic bearings are great, just not for bikes.

hythamfekry

Guess it's better to talk practically and leave the theory for a while ..
People who tried full or hybrid ceramic can share their experience in terms of speed / riding quality.

andr0id

When we get bicycles we can ride where the wheels just spin without touching the ground and without having the weight of a rider, ceramic bearings will be great.

merlinextraligh

the problem is those experiences will be subjective, and likely filled with a fiar amount of placebo effect, and confirmation bias.

Even the extremely marginal benefit claimed by advocates of ceramic bearings are so tiny, there's no way to accurately perceive that benefit from just riding.

Even a very well controlled experiment is unlikely to be able to confirm a 1-2 second difference over 40km. The difference, if there is one, would be lost in the noise.

That said, my personal anecdotal experience with ceramic crankset bearings, pulley bearings and ceramic wheel bearing, I can't tell one iodate of difference in actual riding.

hythamfekry

That's a good point i agree .. it's just for the first glance without considering real life factors "weight , etc.." , you feel you in front of something that looks promising

merlinextraligh

just poking around the internet to see if there's any good data on the watt savings, the information that pops up seems to be almost entirely sales pitches.

Ceramic Speed claim they will save you 10-16 watts. but that assumes you use their coated ceramic bearings for bb and wheels, derilleur pulleys their oversized pulley system, and their race day only chain that has to be replaced every 200 miles and cant be used in the rain, and all this will only set you back $2000 or so.

Even they are only claiming 6-9 watts from just the bearings, a good portion of that is coming from the oversized pulley system, and based on very high quality coated ceramic bearings.

So parsing all their information, it looks like they're claiming 1-2 watts just from the wheel bearings.

snake oil

hythamfekry

well i guess you kinda summarize the situation here .. so regardless of the speed , no difference on the riding feels , right , guess it's a placebo effect as well

K.Katso

Actually I have copies of the Friction Facts test reports where they got the data from. It's not BS, but you can believe what you like. Sure, it's a lot to spend to save one or two watts, but there are a lot of little things that add up. That's the whole idea. Whether it is worth it to one individual or another is up to them, but the data is there.

From the oversized pulley wheel test:

"The data shows that friction decreases in a linear manner with increasing pulley diameter, when plotted as watts vs. total angle of articulation. The experimental results agree with the oversized pulley theory regarding efficiency increases with larger diameter pulleys. The data shows a difference of 0.49 watts between the smallest diameter pulley combination and the largest diameter pulley combination, with bearings and chain tension held constant."

From the bearing test:

"The CeramicSpeed 11T-11T pulleys exhibited lower friction than the generic 11T-11T. Conversely, the DA 11T-11T pulleys exhibited higher friction than the generic 11T-11T. Additionally, these two set of pulleys exhibited the highest differences (CeramicSpeed lower and DA higher) of all five test sets when compared to their generic pulley counterparts, and a difference of 0.35 watts when compared to each other. Again, this is most likely due to the bearing efficiency within each model."

In the BB test, the Ceramicspeed ceramic BB saved more than 1 watt over the DA9000 steel BB. From the report: "The average frictional losses of the ceramic bottom brackets is 0.60 watts, while the average frictional losses of the steel bottom brackets is 1.02 watts."

They compare a lot of other manufacturers and models as well. I agreed to their "honor system" not to share the docs so I can't paste the whole reports in, sorry.

hythamfekry

well , we can agree that how much you spend for a certain gain is depending on each individual budget/taste ..
But what i see here that any gain will be very minimal and hard to feel in real life , we are talking about one watt or a fraction of watt .. as per the no. you mentioned ..

merlinextraligh

.


the differences here are extremely marginal. Average difference in bb's is .42 watts. I'm assuming wheel bearings is going to be in the same range.

A well cleaned chain likely makes a bigger difference. https://www.cyclingpowerlab.com/drive...fficiency.aspx

pretty sure you enter a .42 watt difference in power in most computer power/speed models, and it gets lost in the rounding error.

K.Katso

That's true. However there are others that said that there is no difference, and that is not true. It's simply a matter of whether you want to pay for these marginal differences, in order to add them all up to save a few watts. Most people don't, and I can understand that, but saying there is no difference when there is data to support that there is a difference just isn't fair.

BTW they also tested chain lubes, dry vs. lubed, dirty vs. clean, cross-chaining and ring size efficiency, and new vs. old. The chain test was quite interesting, with the factory lube the Dura Ace chain saved 3 watts over the SRAM Red chain.

hythamfekry

HI Katso , what about the durability of the hubs you tried , are they hybrid/Full ceramic ..

K.Katso

The two wheelsets I have with ceramics, with Campagnolo and DT Swiss hubs, are both hybrid ceramic. I rode those DT Swiss hubs all through the winter in some really bad conditions and they're fine. I'm not worried about them at all. I don't know how they would be if you totally neglected them though, but you could ruin any part on a bike with poor maintenance. I have about 7000km on the wheels with the DT Swiss and about 2000km on the Campagnolos.

rmfnla

That, or the need to justify money spent on a non-existent benefit...

Homebrew01

Shhhhh, the poor ceramic bearing sellers still have old stock to dump.