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Previously when I've had annoying noises from my bottom bracket I've simply discarded it and bought a (cheap) new one. But the last time I replaced it I got a great offer and splashed out a little bit on a Hope Road Ceramic Bottom Bracket. A couple of years on (but only 2,000 miles later) I'm getting noises out of it when I pedal. Due to injury it has sat around for a long time while I recuperated. I'm trying to avoid replacing the bottom bracket if I can.

I don't need help diagnosing the source of the noise. Please assume my diagnosis is correct that the noise is from the bottom bracket - ball bearings or any other part of it including it's fitting to the frame

What I'm trying to understand is:

  1. Is there some maintenance (clean and re-grease?) that I should have been doing but missed? Beyond cleaning it externally I've done nothing to the BB
  2. Does the fact that it's ceramic make a difference to question 1?
  3. Are the ball bearings generally a sealed unit or is it possible to open, clean and re-grease them?

My "bike mechanic" skills are self taught since I was a teenager. Naturally there's things I find I should have been servicing all along or monitoring but simply never knew I had to (for example rim-wear).

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  • Are you sure the noises come from the bearings and not the cups, frame, cranks or pedals?
    – Mike
    Aug 21, 2018 at 13:41
  • I think I did actually cover that carefully in the question. Cups are part of the bottom bracket so that's a possibility, cranks and pedals are not, they have been ruled out. I've explicitly included the BB's fitting to the frame as a possibility. With a carbon frame, it's very easy to know the difference between something in the crank and pedals (with a metallic sound) and something attached to the frame making the frame vibrate (with a plastic sound). The timing and correlation to pealing (not power or gear) rules out the wider frame itself. Aug 21, 2018 at 13:44
  • I can see it now, thank you. If we try to determine whether it is the cups, the bearings or the spindle itself, would you be able to describe the noise?
    – Mike
    Aug 21, 2018 at 13:54
  • Hard to describe. It would be a couple of clicks (or very short crunches) in time with the crank. However the click itself isn't audible. The frame is amplifying it. So all I hear is something tapping on the frame in time with my peddling. It doesn't vary enough with force through the pedals. If the BB was loose in some way I'd expect it to shut up the moment I dropped into the granny ring on the flat, but it doesnt Aug 21, 2018 at 14:03

4 Answers 4

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  1. To the bearings themselves, not really. It's possible to pull the seals and clean/re-grease the bearings while they're still installed, but this isn't something it's expected anyone's going to actually do. (The one you have I believe has bearing seals that are pretty easy to get to, making this easier to do if you want it. Shimano Hollowtech BBs have the bearings covered by a plastic "top hat" seal that's not intended to be removed and re-installed, and usually can't be without ruining it.)

    For all external cranks, it's pretty common to encounter noises that can only be remedied by cleaning and greasing the spindle interface. That might be considered regular maintenance.

  2. No.

  3. In general, all cartridge bearings with rubber seals can have the seals carefully removed, which is something of a skill in and of itself, be cleaned with solvent, rinse, blown dry with air, and re-lubricated. The nature of external BBs is that you won't be able to remove one side's seal, which makes the process more difficult but not impossible. As mentioned above, many external BBs have difficult or impossible to remove parts in the way of the bearing cartridges themselves, and doing anything with the bearing isn't really practical if this is the case.

Another thing that bears mentioning in this conversation is that many Hollowtech 2 compatible external cups can have their cartridge bearings driven out and replaced. Enduro and Phil both make presses just for this. What replacement bearing and seals are appropriate depend on the BB.

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Bottom bracket maintenance - is it a thing? Yes, on open bearing BB. On sealed bearing BB, depending on how the unit is constructed you may get away by swapping bearings. This kind of BB's usually have two indidual cups(threaded) with bearings and a spacer to pinch the bearings. Others are just a plain sealed unit and is composed of two parts. The BB and a threaded ring that goes on the other side for the whole thing to rest evenly. If broken just buy a new one, there is nothing you can do here.

Onto your case Hope Road Ceramic Bottom Bracket looks like the first sealed BB I've described. You will need some sort of jig to press out your bearings, then get a caliper and messure the outside diametre, inside diametre and thickness of the bearing. Even better if you get the SKU of the bearing or the model number. Then go to a SKF Store(or something like that where you can buy bearings by size) and ask for your bearing. Then you will need to reverse the process, make sure you press the bearings parallel to the bottom of the cup. Tolerances in this kind of pieces is tight, if isn't pressed right the axle won't fit, or your new bearing will blow out soon.

I used to have a Oddisey Euro BB with two bearings on each side, for Profile Dj cranks that came with an American BB. The Oddisey BB was just right for the job, but the bearing kept blowing up because the spacer wasn't long enough.

Hope this works for ya.

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Some points in this answer are duplicates of others already raised, but some are not. I am writing this answer for the general audience, as it’s likely the original poster resolved the problem by now.

Most modern bottom brackets with cartridge bearings are not meant to have their bearings serviced. It is often hard to access the bearings, as others have noted. In some cases, manufacturers explicitly design their bearings to be serviced, and may require it for warranty coverage. If you don’t see explicit instructions to do this on their website, you can assume they aren’t designed for service. The current instructions for Hope bearings don't mention service, and that was likely true of the BB model the original poster referenced.

Users should naturally avoid spraying water, especially pressurized water, right at their bearings (i.e. spray your bike from the front or back, or if from the side, avoid aiming right at the BB and the hubs). Users should also be aware that rides in the rain or rides where the bearings get submerged will affect bearing life.

Optional reading: serviceable cartridge bearings

Ceramicspeed and Kogel focus on low-friction ceramic bearings, and they do explicitly require riders to regrease their bearings. Chris King doesn’t exclusively sell ceramic bearings and has historically focused on durability rather than low friction, but they also require users to regrease their bearings. Their service instructions are here. They have one protective sleeve over the bearing, plus a removable metal clip, plus a rubber seal. They explicitly say "The seal is delicate so take care. It should come off very easily..." The photo below shows the removal process with a penknife.

enter image description here

I am not completely sure about this part, but my impression is that many cartridge bearing seals may not be designed to be repeatedly removed. Enduro Bearings, which supplies bicycle bearings, alludes to this on their page on seal design. They list 5 different sealing arrangements they offer. On one of them, the Enduro SRS seal, they state:

... these seals employ a snap ring that can be removed with a small knife for quick and easy servicing. These seals can be removed with no danger of bending them while performing lubrication service, ensuring they will spin as smoothly after.

This implies that many other seal types they offer are not designed for removal and replacement. My impression is that seals not designed for removal might be damaged if you remove or reinstall them. Kogel alludes to this in their instructions on bearing service, and their instructions seem to assume that the old seals should be discarded. However, one of their representatives said to me in a phone conversation that it was possible to reuse their seals if they were intact.

Additionally, seals can be designed to have more or less drag - for example, seals that have a more solid contact with the bearing races will have more drag. The tradeoff, as I understand things, is that lower-contact seals should be less resistant to contamination. If a seal is less resistant to contamination, then unless the whole bearing is designed to be an extremely high cost disposable item, it would make sense to make the bearing system serviceable. Kogel’s seals came off easily when I serviced them. I’d assume they are a light contact seal.

Last, the low-friction bearings may have less grease, and more viscous grease. My understanding is that less viscous grease has a shorter lifespan. More viscous grease should prevent more dirt from entering the interior of the cartridge than less viscous grease. I suspect that general purpose bicycle greases are on the more viscous side unless specifically identified. Chris King, Kogel, and Ceramicspeed all sell lighter and heavier greases for a range of use cases. If you use a lighter grease, I would suggest planning on more frequent service.

Back to point 2

This was where the OP asked:

Do ceramic bearings require different maintenance procedures?

As stated elsewhere in my answer, I believe that a ceramic bearing of similar construction - including seal design, grease type, and amount of grease filled in the bearing - to a steel bearing should not require materially different maintenance procedures. If the manufacturer instructions did not require periodic maintenance, there was nothing the OP could have done differently. Others in this situation might want to double-check with the manufacturer for specifics.

That said, because of their high cost and slightly lower friction, I think that ceramic bearings on bikes may generally be designed with lighter seals and grease fills than average steel bearings designed for durability. Bearings designed to optimize friction are likely to require more maintenance.

Creaking should be a sign of a loose fit, not necessarily of failure due to contamination

Speaking in general, a) creaks can sound like they’re from the bottom bracket but actually come from other parts (e.g. loose skewers are a frequent culprit), and b) creaks are usually caused by parts that fit loosely, e.g. a bottom bracket in a shell that is out of tolerance, rather than contaminated bearings. In general, I believe that contamination will cause the bearings to feel rough, and that they shouldn’t cause audible sounds unless the bearing is very bad. This is not aimed at the OP, as we were asked to assume that they had isolated the noise. It is more for the general audience.

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    Answer to an old question of course, but a lot of useful information there. Thanks. On the last part, the noise did eventually go away after a couple of times when I stripped the bike of parts, cleaned and refitted. I still think it was coming from that region on the bike. Dec 1, 2021 at 9:21
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    @PhilipCouling good to know. I came across this while cleaning up the ceramic tag. I actually was targeting the general audience more than you specifically, since this question does come up.
    – Weiwen Ng
    Dec 1, 2021 at 12:42
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Most modern 'unit' bottom bracket bearings such as the Hope BB you have are not meant to be disassembled or serviced.

Some BB models can be re-greased by carefully popping off the plastic seals. I've done this on a Shimano Ultegra Hollowtech BB.

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