are there any ceramic octalink bottom brackets on the market?
i would like to use an ceramic with the srm amateur. is it possible?
i have been doing some surfing and it dosent look like there is a ceramic octalink on the market.
is it possible to overhaul a dura ace and fit it with ceramics or upgrade the srm to fit on the new external style hollowtech bb’s???
are there any ceramic octalink bottom brackets on the market?
i would like to use an ceramic with the srm amateur. is it possible?
AFM knows of a guy in the UK that will replace the bearings in an Ultegra Octalink BB with ceramics. You should PM him if you’re interested.
Of course, the real question is “Why?” A well adjusted DA octalink BB is as low drag as any BB with ceramics…and if there IS any difference, you’re talking magnitudes of milliwatts of difference.
ah… i have misguided so.
i was lend to believe the difference was significant.
ah… i have misguided so.
i was lend to believe the difference was significant.
Yeah…well, IMHO there’s a lot of “misinformation” on this subject 
The majority of the “drag” people feel when comparing BBs unloaded is seal drag…and the DA octalink BB doesn’t have very “heavy” seals, which is part of the reason that when octalinks were the top of the line DA parts that mechanics (especially on the Protour where they use pressure washers to clean the bikes (!)) swapped them out for Ultegra BBs since the bearings were better sealed and the installation was easier (i.e. just torque it and go since it’s a cartridge bearing, whereas the DA actually requires an adjustment to get it right). That kept them from having to rebuild the BBs all the time since the grease was getting washed out.
If it wasn’t for me running a CinQo on my road bike right now, I’d still be using a DA octalink BB…the TT bike has a WELL broken in Ultegra BB in it since I’ve occasionally been swapping the CinQo onto it and it’s easier to install than the DA BB 
Ceramic bearing themselves are much harder and rounder than conventional bearings. A Record or Dura Ace quality bearing is a grade 25 bearing. Your typical ceramic bearing is a grade 5. Five times rounder and the ceramic bearing could easily pulverise the DA. Seal drag is another thing altogether. And many sealed bearing sets are not adjusted well, causing premature wear and wasting money. Most sealed cartridge BB’s are a drag wasteland because of those two things, seal drag and poor adjustment. I can’t speak for Red, because I haven’t seen enough of them yet.
I can tell you that a ceramic bearing makes heaps of difference. I sold my track bike, but a while I before I did so, I installed ceramic bearings in both wheels and bottom bracket. WOW it really makes a difference. And the stock bearings were no slouch to begin with. But that was a loose bearing set that I could adjust perfectly.
Just ask inline skate racers if they would race with anything else.
Ceramic bearing themselves are much harder and rounder than conventional bearings. A Record or Dura Ace quality bearing is a grade 25 bearing. Your typical ceramic bearing is a grade 5. Five times rounder and the ceramic bearing could easily pulverise the DA.
No, they’re not 5 times rounder.
It roundness in MILLIONTHS, thus grade 5 has a deviation of 5/1000000 and grade 25 has a deviation of 25/1000000.
That means grade 5 is 0.000005 times rounder than grade 25.
But they are five times more expensive. $$$
are there any ceramic octalink bottom brackets on the market?
i would like to use an ceramic with the srm amateur. is it possible?
AFM knows of a guy in the UK that will replace the bearings in an Ultegra Octalink BB with ceramics. You should PM him if you’re interested.
Of course, the real question is “Why?” A well adjusted DA octalink BB is as low drag as any BB with ceramics…and if there IS any difference, you’re talking magnitudes of milliwatts of difference.
I also have a procedure (electonic with pictures) and have done the deed twice myself. It takes 14 total of the 7/32 inch diameter balls. Patience is needed especially when using the lighter greases but doable in ~ 2 hours. But as Tom points out (and educated me) it’s low hanging but very expensive (per milliwatt) fruit. The seals can be left out of the rebuild for track use.
Even if you did find one - That would be a waste of money.
I have a F1 Ceramic http://www.f1ceramicbearings.com/bicycleshop.html shimano BB for sale if you want it, it has < 200 miles on it. (I am switching to SRAM)
Even if you did find one - That would be a waste of money.
hahahahhahaha. She would slap me silly daily if she knew how I spent my money for things “I need”
I have a ceramic BB and a DA version, I swear the ceramic feels smoother. Its not a huge difference but I can certainly feel it.
I have a ceramic BB and a DA version, I swear the ceramic feels smoother. Its not a huge difference but I can certainly feel it.
Do both have the same seal configurations and grease? When you say you can “feel” it, do you mean with your hand? If so, do you realize just how small of a force difference you can detect manually?
Do you still have the procedures for the 6500 bb rebuild? Ancient thread I know I would send a pm but new member…
Thanks
The tool for the 6500 costs almost as much as a new BB. Buy a new one. No PM needed.
Ahhh…the inline skaters…when they are not designing new thermal greases and dissecting the theory of how round a round bearing is…they are figuring out bearing material. How about we first focus on the fact that a properly adjusted cone/ball/race is a “faster” bearing when under many of the angled loads that we see in cycling (and skating for that matter). How about we focus on the fact that for an upper jockey wheel a bushing is far more effective in the use than any bearing (due to the needed side play). Cart. bearings are a production and consumer thing - not a performance thing (well, life span performance more than time on the 1/1000th hand of your fancy watch. Can we speak to the FACT that a QR skewer can over load almost any wheel bearing just by clamping the wheel (unless the wheel is properly adjusted either slightly loose, or as you can with Campy wheels - while under the load of the clamped QR). I mean, we are seriously slicing hairs here - lets get into the nitty gritty.
Thanks… Not helpful…This is more of just a shout out to Al for the info.
Funny, this thread is from 2009…and the facts have not changed.
Do you still have the procedures for the 6500 bb rebuild? Ancient thread I know I would send a pm but new member…
Thanks
Yes, I still have them. It’s not an easy thing but doable with some patience and good lighting. I’ve done it 3 times. Taking it apart isn’t too hard which is necessary to see if it’s worth rebuilding. Maybe make a few more posts and send a PM ??
But why? Here is what you need to do. Figure out how much money you make an hour at work. Then, figure a new BB is about $30 retail. Then factor in the time - about three hours. The mess (grease blahblah blah). And the expected result.
I would rebuild it, I get it, I enjoy it. But, I would rebuild it after I purchased a new one and installed it.