Creaking Praxis BB

[Butcher]

Sorry to dig up an old thread

No issues, Highdraw is no longer here. You're [We're] safe.

[goodboyr]

Sorry to dig up an old thread

No issues, Highdraw is no longer here. [emoji106] You're [We're] safe.

Lol. He has been seen.............

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[pdlpsher1]

From the picture it appears the carbon BB shell has begun to separate from the frame. If the BB is glued to the BB shell then on day the BB will come loose when the BB shell is separated from the frame.


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[blue151]

Thanks for all the feedback and anecdotal experience.

Glad to say that despite the wrong loctite, the bb is silent again!..

[Butcher]

That frame is already for the scrap heap. He's just getting a few more miles in it until it does get there. It's a good experiment for certain.

[Calnago]

@blue151: when they used loctite 242, do you know if it was just in the threads of the Praxis BB where the two pieces screw together? Or did they remove the entire BB from the shell and put the stuff on the inside of the frame shell and the outside of the praxis surfaces that mate with it? If it's the former, that's fine and your issue was nothing more than some creaky threads. Normally Praxis sends their units out with a copper based antiseize on the threads. But if they removed the unit, and the offending sound was indeed coming from the interface between the frame shell and the Praxis surface, then the loctite 242 is serving the same purpose as if they had just put some grease in there. That is, it's a temporary fix and allows the micromovements to happen without noise, for a while. Blue loctite does not have nearly the strength to be able to withstand the pedaling forces in a BB. You could put almost anything in there and as long as it lets the surfaces slide around on each other it will be quiet for a while, till it's not again. In the meantime the movement continues to wear the shell and over time... well, you get the point.
Even the simple act of removing and reinstalling without adding or doing anything can make things quiet for a while just by repositioning a bit. But in the end, the only solid fix is to ensure there is no movement between the frame shell and the BB surfaces. That's what a retaining compound is intended to do. You can still remove it when the time comes but it does take a rather forceful hit. Heat is not really a practical way to break the bond when installed in a carbon fiber (and resin) shell since it could soften the resins of the composite, not to mention wrecking any paint.
Anyway, glad it's quiet for now. Enjoy it, as creaks and clicks are just so annoying.

[Calnago]

From the picture it appears the carbon BB shell has begun to separate from the frame. If the BB is glued to the BB shell then on day the BB will come loose when the BB shell is separated from the frame.


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The delrin cups are indeed now "glued" to the frame via the DP420 epoxy used to both repair the frame shell and bond the cups so that they can't spin within it. But the Praxis BB itself is held in the cups primarily with the loctite retaining compound, since even the expanding collet was not enough to keep it fully tight. It "should" be removeable if necessary, the issue being if the cups themselves are still useable at that time. Or, I've even thought in the event the bearings themselves wear out I could use a bearing puller to remove just the bearings from the Praxis cups (without removing the BB itself) and just press in some new bearings. Either way, this whole exercise was kind of a Hail Mary attempt at saving an otherwise trashed frameset and extending its use a while longer. Has worked perfectly so far and see no signs of issues. Kind of surprised me since the damage was so severe.

[blue151]

@calnago: the 242 was only applied to the interface between the shell and the BB and not the threads - sounds like it noise may come back one day.. but hopefully not. The BB was previously installed with antiseize as specified however this didn't seem to hold the bb tightly enough to prevent an noises. Didn't really want to go down this path again.

I'll probably try and source some 609 myself (and whatever the primer number is - i saw it earlier in the thread).

Alternatively I may go down the path of another BB maybe... c-bear or maybe kogel... will have to do a bit more research first.

[cobym]

Anyone has experience using Loctite 638 for the creaks?

According to the description from loctite, it works even with plastic, so I suppose this does not need an activator/primer.

[Calnago]

Loctite 638 fills bigger gaps than 609. Trek recommends it for installing the seal seats for a Campy installation. But you should still use a primer with it if applying to an inactive material, such as Carbon and/or titanium.

[cobym]

Thanks.

This creaking has me cursing why press fit BBs were invented and adopted in the first place a few years ago (or several). Then the thread-together press fit BBs came out, and I thought this (I use a Praxis M30 for my PF30 frame) was the solution and BB30/PF30 frames were ok again. Turns out its not. (So thats why someone tried to sell me a very slightly used M30 bb for a good price).

Then I saw this thread, and its by far the most valuable press fit BB problem-solution resource known to man. Obviously, the frame makers and BB suppliers dont say a peep about how worthless the whole press fit BB idea is, or how theyre going to help hapless buyers. Going back to regular threaded BSA BB equipped bikes.

Sorry about the rant. But I meant that part where this thread has been SO HELPFUL!!

[simplemind]

This has been a good thread. My Yeti MTB has a Praxis BB and has been silent since new. Don't know if they use a locker or not. That said, is there any experience with the Token Ninja Adapter [url]https://www.tokenproducts.com/bottom-brackets/mountain/ninja-bottom-bracket/url]? Looks like they use a "fiber filled plastic" as a buffer between the adapter and the shell. The few comments I have found are quite positive with no indications of creaking. Any experience here?

[Machined09]

Sorry to dig this thread up again. I too is having this epic creak but i seem lock the loctite procedure. Sorry its stupid question but where to i apply the loctite into the bb? Cheers from Australia.

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[AJS914]

You have a Praxis? You apply the loctite where Praxis says to apply the anti-seize.

I just ordered a Praxis - Ultra Torque BB for an old Time frame I'm fixing up. It has an aluminum BB30 bottom bracket. I'm going to Loctite it in with 609 as suggested rather than using anti-seize.

I gather that since it will be aluminum to aluminum that I don't need to use activator. Right?

Where do you guys buy 609? Do they sell single use packets anywhere? On Amazon, I see 10ml for $16 and 50ml for $19. Is it better to buy it at the hardware store though I'm doubting they would even carry something so esoteric.

[CBJ]

I got mine on a production bike and it was not perfect but when the LBS reinstalled according to the specs it has been flawless. Now that I live in a place with more rain it will be interesting to see how it holds up.