Omnium's GXP Cups bearings replacement

Hi guys,

I am pretty sure if well known the issues with the GXP external bearings that are inside the cups that come with the SRAM OMNIUM's that are quite popular in the fixed gear world.

I come down to the conclusion that the cheapest/easiest way to get the expected crackling noises that eventually they start to make, is in sum, replace the bearings in both sides (NDS and DS).

Anyone went through the same issues? How did you sorted that in a more permanently?

I am looking at best bearings without going too crazy with budget of course, shut out your links, I am all ears.

Thanks in advance

I'm far from a SRAM fan but GXP is alright if fitted properly. No BBs last forever.

The cheapest easiest way is to replace the whole thing and fit it properly. Changing bearings is entirely pointless considering the BB is under £30.

If you're so desperate, just get a HOPE BB and fit adapters, or more insanely, get a CK and fit adapters.
I don't know why, the standard GXP is good enough.

They were designed to swerve Shimano patents on Hollowtech so allegedly have a bit of a fatal flaw in the design that accelerates wear and tear with one side taking more load than the other

Hi Chak, thanks for the reply.

Something like this what do you mean by adapter? Enlight me

Hope BB's only come in 24mm axle od. SRAM is 24/22, you'll need a shim.

Thanks a lot Chak! Definitely looks a more solid solution and hopefully without the GXP issues that are known for.

Do you actually have issues with your current GXP BB?

Why does it come with two shims?

I guess one if for the NDS one for the DS

How many people with GXP issues have you read about?
Several?
Tens?
How many people do you think are using them without issues? Thousands? Tens of thousands?
I just replaced the GXP on my daily bike after 10,000km. Not a creak or sound from it till the end.
Get your frame faced and have someone qualified install your bottom bracket.

Can't quantify, but funny is I know at least 2 other guys in person that have the same issue with them.
After mine started with the noises, I obvs started to look online before I do anything. And Noticed that is a fairly frequent issue, almost ritualistic for some people that have to change bearings/cups every year or so dependingly on how much they ride.

All I am doing is trying to get some advice/information on this before I drop to a bike shop that atm is way too busy for any "small" things like this.

Anecdote is not data but I have a 10 year-old GXP BB on Omnium cranks. No creaking.

Sorry if I didn't collect accurate statistics carefully before I created the topic asking for some help :)

Just keep buying them and replacing them. It’s uneconomic to spend 3 times the price for not 3 times the durability. They’re just cups and bearings.
But really, look at getting your bb shell faced

But the drive side is already 24mm, it’s just the nds thats 22. 🤔

I am pretty sure if well known the issues with the GXP external bearings that are inside the cups that come with the SRAM OMNIUM's that are quite popular in the fixed gear world.

Am I the only one that had a stroke reading this?

Anyway, the problem with the gxp system is that all the axial load is taken in the non drive side bearing. Most other bottom bracket systems share the axial load between both sides.

Proper facing of the shell and installation may well help prolong the life of the bearings but in my (and many, many other people’s) opinion, it’s a flawed system so anything you do is going to be fighting a losing battle.

Personally I don’t see using a bottom bracket like the Hope as as viable fix. The nds bearing in a gxp bb has a special elongated 22mm ID inner racer that gets held between the step in the axle and the crank arm. Using a spacer inside a 24mm bearing seems like a bodge to me and I don’t imagine that it can support the axial load as well as the original which, as above, is already a flawed way of doing it.

The step down in the axle to 22mm also probably means the nds bearing in a genuine gxp bb is using larger balls which would make sense since it’s supporting all the axial load. Using a spaced bearing means you are putting those loads into smaller bearings and that can’t be good.

I suspect the reason we don’t hear many people complaining about the longevity of the Hope bb is that there aren’t actually that many people using them.

In my personal experience, when fitting my own GXP cranks, there is a little play in the crank arms even at 30nm+ and the required 40 just takes out the play as they get really tight which says to me that there's next to no axial load.
Now if your BB shell was 68.5 or 69mm wide which as you'll know is how they come from the supplier, the crank is going to be pressing on those bearings long before the 40nm required torque

There are axial loads being put into the system though and all that load is taken in the nds bearing as it’s the only one held axially.

The ds floats axially and is only supported radially.

On ht2, both crank arms abut the bearings and the axial loads are therefor split between the ds and nds.

I also think ht2 is superior as you have the preload cap adjustment, gxp only holds the nds bearing, doesn’t really preload it.

Let the guy buy whatever BB he wants to work for him. Will a Hope be better? It won’t. It’ll creak at some point too due to the steeped design.

Would it be cheaper to destroy and replace the standard one? It’s what most on here do.

A hope one is still better than replacing the fucking bearings on an original one. That’s just self torture.

I really appreciate your knowledge and in my all humbleness, I came here to exactly seek for help. Thanks for that. I do not know how I caused you any stroke. If was due my shitty English, I am sorry but I am not Native and I didn't wanted to hurt your heart. If was due to anything I said, sorry but when you look up online, is a quite common issue with this setup, I didn't say anything wrong, is a common issue with a common setup. Coicidence? I don't think is a feature :)

Thanks for clarifying on re-Hope BB. I just mentioned such HOPE BB because someone recommended me and I wanted to check thoughts on it. Thanks for the input.

Would it be cheaper to destroy and replace the standard one? It’s what
most on here do.

That sounds the most affordable/viable solution to me VS trying to get out of the GXP system an indestructible system, as someone said: is a lost battle from the beginning. Cheers

I do not know how I caused you any stroke. If was due my shitty English,

I was only kidding, apologies for making fun of your english, I'm sure its ten times better than I'd manage in any other language.

To clarify, I would just go with a standard GXP bottom bracket and get your bb shell faced before fitting. It's not the perfect system but they are pretty cheap and some people seem to have very few problems so it should last you alright.

Are the current bearings actually worn or do you just have noise?
I don't run Omnium any more but when I did I regularly found that after a few winter rides (on wet farm roads) I would get a gritty feeling from the cups.
(If you don't mind taking the cups in and out regularly) I was able to flush all the crap out with WD40 and then re-lubricate with a spray grease. It was a bit of a bodge and I got fed up with taking the cups out after every few shitty rides but it may well have preserved the bearings. I used them for about two years and they still ran smoothly when I sold them....

They don't feel worn out, I will have a spare time this weekend to re-grease them and see what is going on. They just that noise when stronger revolutions are pressed, per example going up-hill, and yes seems to be on the NDS, but hard to tell 100%.

Is Park Tool PPL-I any good for re-grease after good flush?