GXP bearing in BB90 has tiny bit of play

[Greenduck]

Hi everyone,

I just replaced my left side bearing with a Wheels Manufacturing for GXP as I've installed a Quarq DFour91 power meter.



I have put a wave washer in the right side between the crankset and the bearing. The crankset spins smoothly and there's no sideways play. But there is a tiny bit of up down/forward bakwards play if that makes sense? Like the inner diameter of the GXP bearing is just 1/10 of a mm to large.

Am I doing something wrong, do I need another bearing or is it just the way it works with GXP in a BB90 shell?

[alcatraz]

The inner race of the NDS bearing should be clamped by the crank and thus not move.

Have you tightened the crank bolt?

If you need more high quality gxp bb90 bottom brackets a tip is to buy the dirt cheap sram original bb86 one and harvest the bearings from it.

Sometimes a gxp bb is in fact a shimano bb with a conversion kit reducer sleeve. In such cases the nds side can exhibit radial play. The wavy washer needs to be stronger and take out the axial play, but the radial play will remain.

[CamW]

Knowing BB90 your bearing seat has probably become slightly enlarged so the bearing is actually moving in the frame.

[Henryexige]

The inner race of the NDS bearing should be clamped by the crank and thus not move.

Have you tightened the crank bolt?

If you need more high quality gxp bb90 bottom brackets a tip is to buy the dirt cheap sram original bb86 one and harvest the bearings from it.

Sometimes a gxp bb is in fact a shimano bb with a conversion kit reducer sleeve. In such cases the nds side can exhibit radial play. The wavy washer needs to be stronger and take out the axial play, but the radial play will remain.

Get the BB infinite repair version.




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[Mr.Gib]

Knowing BB90 your bearing seat has probably become slightly enlarged so the bearing is actually moving in the frame.

Sorry to say this is most likely the issue. A common issue with certain Trek models with carbon BB shells. The bore is likely not round but oval. Trek in fact has a special bearing made to solve this problem. It is slightly oversized. This will deal with the play but will not address any out of round issues. And a round bearing forced into an oval hole means poor performance and a short life. I had to give up on a Trek because of this very problem. I do believe that Trek has a program where they re-build the BB but unless you are near Wisconsin, it is probably not worth it. And of course because it's BB90, there is no decent thread together solution that can help.

[romanmoser]

try to have a new frame under warranty
sell it

buy a frame with a decent bb standard

thanks

[alcatraz]

GXP NDS is often a loose fit. Let's let the OP reply first before jumping to conclusions.

Is the crank moving with or without the bearing?

Did the NDS bearing press into the frame with much less effort than the DS side?

[tleo]

As alcatraz stated the NDS bearing is a very loose fit for whatever reason. I experineced this personally when using bearings purchased from Quarq on a Quarq crank.

Hambini also notes this in his YouTube video about the GXP crankset. See starting about 6:10 on the video. He is not much of a fan of GXP.

https://youtu.be/dkAxXNYzBGg?t=359

[Visus]

Probably, as mentioned, oversized bearing bore.

Try to exchange your frame (lifetime warranty for original owner with TREK frames)

If not possible:

1) Try the oversized bearing kit from TREK. Thought if the bearing wiggles inside the frame this might not suffice
2) https://www.tokenproducts.com/bottom-br ... nja/bb3724 but be ready for low bearing life
3) search for someon who can rebuild the bearing bore/laydown a bit of carbon for a snug fit

But before doing that remove the crank and verify that the outer race wiggles inside the shell, maybe it's just a bad bearing. If you can't push the bearing out with your hand/fingers it should be snug enough

[MitchatTrek]

Hey @greenduck,

If you haven't yet, bring your bike into your local Trek dealer to have a warranty claim submitted. This way we can look into it first hand. If you did want to try something at home, use the stock Trek bearing we sell which is part number 524556 for your GXP BB90 setup. If no luck, we'll have to look at other options like the OS bearings.

[FIJIGabe]

Hey @greenduck,

If you haven't yet, bring your bike into your local Trek dealer to have a warranty claim submitted. This way we can look into it first hand. If you did want to try something at home, use the stock Trek bearing we sell which is part number 524556 for your GXP BB90 setup. If no luck, we'll have to look at other options like the OS bearings.

This. Having recently done this repair on my wife's Domane (BB90, Shimano components), I can tell you that the repair is relatively quickly turned around by Trek (maybe a week after receiving the bike, they had it back at the shop I took it to). The bearing hole grows, over time - it's an unfortunately problem with these frames.

I don't know if Trek will do a warranty repair if the oversized bearing will fix the issue, but I doubt they will.

Also, I don't know how much they'll charge if you bought the frame second-hand. I'm sure the repair isn't cheap, however (especially with shipping charges).

[spud]

I looked into a BB repair for another issue, and the quote from Trek was $300 to rebuild and machine the carbon seat area. Ended up not needing it as the Campy installation kit bonded into the damaged areas and fixed the issue.

[Greenduck]

Hi everyone and thanks for all the replies.

It's a brand new Trek Madone SLR Disc frame so no need for a larger bearing. I found out that it was torqued too low even though I thought I had it torques properly. Took it to my go-to bike shop.

So everything is working properly now.

THANKS!