Creaking Praxis BB

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Trkorb
Posts: 146
Joined: Sat Jan 19, 2013 1:17 am

by Trkorb

Hey guys,

I have recently built up a CAAD10 frame and am using the Turn Zayante crank with the Praxis BB30 expanding bottom bracket. I chose this particular set up specifically so I never had any BB creaking problems, and it seemed like a pretty foolproof solution to me (although heavy!).

However, 50km in and the dreaded creak occurs, I reinstalled as instructed by the manufacturer, and yet again after 50km creaking is back. So I sent the crank and BB back to the manufacturer but they said they are unable to replicate the fault and said if you continue to have problems just buy a new BB...

They also instructed me that the BB has to be tightened very hard to hit the internal stop, so I made extra sure on the 3rd installation that it was extremely tight (over 150NM in the end!)

BUT now, 50km later, it's creaking and I'm at my wits end. Does anyone have any experience or ideas? Loctite? will a new BB solve the problem? I just want a silent bike!!

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boysa
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by boysa

I've installed three different Praxis Conversion BB's on my CAAD 10. Two were GPX and one was Shimano. All three started off brilliantly, and then after one or two rides... creak, creak, creak. Not excessive, but it's there every time I'm out of the saddle. Annoying as hell. If I pull the bb, clean and replace, it's always the same story. One or two rides and the noise returns. I've tried installing it with just the anti-seize, with grease, bone dry. All have given the same result. I have not tried loctite, but mainly because I've just given up. Now that I'm sitting here thinking about it, however, I believe some loctite on the NDS might do the trick. Yes, I'm going to give it a go this week.

FWIW, I've also tried the Wheels Mfg. Conversion BB and had the same result. Can't recall if it was better or worse. Probably about the same.
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dton13
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Joined: Tue Nov 12, 2013 9:12 pm

by dton13

What grease are you using? Mine starts to creak once it dries out, about every 6 months or 5-6000 km in the dry, shorter interval in the wet. When I contacted Praxis I was told this was a normal interval.

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Rick
Posts: 2035
Joined: Sat Aug 29, 2009 4:30 pm

by Rick

I don't want to spark another controversial and contentious line of posts, but does your setup include a wave washer ?

Trkorb
Posts: 146
Joined: Sat Jan 19, 2013 1:17 am

by Trkorb

boysa wrote:I've installed three different Praxis Conversion BB's on my CAAD 10. Two were GPX and one was Shimano. All three started off brilliantly, and then after one or two rides... creak, creak, creak. Not excessive, but it's there every time I'm out of the saddle. Annoying as hell. If I pull the bb, clean and replace, it's always the same story. One or two rides and the noise returns. I've tried installing it with just the anti-seize, with grease, bone dry. All have given the same result. I have not tried loctite, but mainly because I've just given up. Now that I'm sitting here thinking about it, however, I believe some loctite on the NDS might do the trick. Yes, I'm going to give it a go this week.

FWIW, I've also tried the Wheels Mfg. Conversion BB and had the same result. Can't recall if it was better or worse. Probably about the same.



Well this does not bode well! :cry: Annoyingly because I bought the Zayante I have no other choice of BB's due to the 30mm to 28mm step

Were you planning on just using loctite on the interface between frame and BB? I think that's probably what I'm going to do as well.


In terms of grease I am using anti seize copper grease on the BB Frame interface, and Green Motorex grease for the spindle interface! I've tried using minimal grease and also packing the thing full of grease, neither of which seemed to help.


Also, yes the set up does include a wavy washer! But as seen above Boysa's set up with GXP or Hollowtech cranks will not have so in this case I don't believe it is the contributing factor.

highdraw

by highdraw

Oliver, I wouldn't give up on the Praxis BB just yet.
What I would do:
1. Uninstall everything.
2. Mineral spirits/degrease both BB alloy cup bores and Praxis sleeve
3. Apply activator to interfacing surfaces.
4. Apply Loctite 609
5. Torque Praxis shell until you hit the stop fully
6. Apply light coating of grease to crank spindle.
7. Install crank ensuring that there is sufficient preload to isolate the crank side to side by the wavewasher.

You should be good. Grease is basically a short term solution to creaking. If you want it quiet longer term, you need to Loctite BB30 to keep it quiet...either with Praxis or conventional BB30 bearings. Either are easy to get apart. Loctite 609 is formulated to have little shear strength. Objective with the formulation is serviceability and offers just enough strength to keep the Praxis sleeve or BB30 bearings in place. Creaking is simply micro movement and Loctite negates this.

See below:
Attachments
Cannondale BB30 Loctite.jpg

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itsacarr
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by itsacarr

Anecdotal as per my own experience but making sure you have a decent amount of anti-seize on the threads has been important. As well as making sure it's tightened down enough - on a couple of installs it hasn't completely settled in.

Definitely don't give up though, I have had and installed the BB on maybe a dozen SL4\New Tarmacs.

Good luck.

highdraw

by highdraw

Sorry if I disagree with your advice itsacarr. Its isn't the sleeve thats creaking. Putting antiseize on a Praxis collet thread will do nothing other than make it more weather proof and allow getting the Praxis BB apart if left on the bike a long time thru poor weather conditions. The thread is under preload when the Praxis BB is tightened to full lock. Creaking occurs between the O.D. of the Praxis sleeve and the I.D. of the BB30 alloy bores. Some of course place grease or antiseize on this interface to quiet a creak but few understands why it will start creaking after a few weeks.
Basically what you have is a pump. Heresy you say? Its a micro pump. Few understand this dynamic so will explain. When an owner or bike shop installs a Praxis BB or even std. BB30 bearings on a BB30 bike and uses grease to facilitate press of the sleeve or bearings, a small amount of grease is captured between the sleeve or bearings and the BB30 alloy bores inside the BB shell. This thin film of grease is in effect a controlled volume. A captured very slender volume of grease...but in essence this volume of grease isn't truly captured and hence the problem. When applying a lot of pressure the pedals there is a cantilevering of the bearings within the shell. Grease is a fluid and all fluids are incompressible. But the controlled volume isn't truly closed. It is open on the outboard side. With repeated cyclic loading the bearings fractionally toggle within their bores...this is a very minute displacement. This grease film dissipates with repeated cyclic loading because the grease hydraulics out of the outboard gap. In effect the grease is pumped out between the OD of the sleeve or bearing and the I.D. of the 42mm BB30 bore(s). Once the grease is pumped out, the creaking begins.

To mitigate this, simply use Loctite instead of grease. Loctite is a low strength adhesive that hardens and doesn't have the amorphous quality of grease. In effect when it hardens it becomes a spacer filling all the micro voids between sleeve or bearing OD and bore I.D. It can't hydraulic out. Further is stabilizes the sleeve or bearing because of its adhesive quality. If a Praxis sleeve or BB30 bearings are Loctited in place and a crank has proper preload aka wave washer compression or mechanical preload adjusted properly and bearings are good, it can't creak.

Trkorb
Posts: 146
Joined: Sat Jan 19, 2013 1:17 am

by Trkorb

After everything I have tried I really believe loctite is the only solution!

I'll have to order some and will report back if it helps!

goodboyr
Posts: 1414
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

highdraw wrote:Sorry if I disagree with your advice itsacarr. Its isn't the sleeve thats creaking. Putting antiseize on a Praxis collet thread will do nothing other than make it more weather proof and allow getting the Praxis BB apart if left on the bike a long time thru poor weather conditions. The thread is under preload when the Praxis BB is tightened to full lock. Creaking occurs between the O.D. of the Praxis sleeve and the I.D. of the BB30 alloy bores. Some of course place grease or antiseize on this interface to quiet a creak but few understands why it will start creaking after a few weeks.
Basically what you have is a pump. Heresy you say? Its a micro pump. Few understand this dynamic so will explain. When an owner or bike shop installs a Praxis BB or even std. BB30 bearings on a BB30 bike and uses grease to facilitate press of the sleeve or bearings, a small amount of grease is captured between the sleeve or bearings and the BB30 alloy bores inside the BB shell. This thin film of grease is in effect a controlled volume. A captured very slender volume of grease...but in essence this volume of grease isn't truly captured and hence the problem. When applying a lot of pressure the pedals there is a cantilevering of the bearings within the shell. Grease is a fluid and all fluids are incompressible. But the controlled volume isn't truly closed. It is open on the outboard side. With repeated cyclic loading the bearings fractionally toggle within their bores...this is a very minute displacement. This grease film dissipates with repeated cyclic loading because the grease hydraulics out of the outboard gap. In effect the grease is pumped out between the OD of the sleeve or bearing and the I.D. of the 42mm BB30 bore(s). Once the grease is pumped out, the creaking begins.

To mitigate this, simply use Loctite instead of grease. Loctite is a low strength adhesive that hardens and doesn't have the amorphous quality of grease. In effect when it hardens it becomes a spacer filling all the micro voids between sleeve or bearing OD and bore I.D. It can't hydraulic out. Further is stabilizes the sleeve or bearing because of its adhesive quality. If a Praxis sleeve or BB30 bearings are Loctited in place and a crank has proper preload aka wave washer compression or mechanical preload adjusted properly and bearings are good, it can't creak.


The praxis instructions are quite specific to specify antiseize on both the threads and the shell interface.............

http://www.praxiscycles.com/wp-content/uploads/conv_kit_instructions.pdf

Trkorb
Posts: 146
Joined: Sat Jan 19, 2013 1:17 am

by Trkorb

goodboyr wrote:
highdraw wrote:Sorry if I disagree with your advice itsacarr. Its isn't the sleeve thats creaking. Putting antiseize on a Praxis collet thread will do nothing other than make it more weather proof and allow getting the Praxis BB apart if left on the bike a long time thru poor weather conditions. The thread is under preload when the Praxis BB is tightened to full lock. Creaking occurs between the O.D. of the Praxis sleeve and the I.D. of the BB30 alloy bores. Some of course place grease or antiseize on this interface to quiet a creak but few understands why it will start creaking after a few weeks.
Basically what you have is a pump. Heresy you say? Its a micro pump. Few understand this dynamic so will explain. When an owner or bike shop installs a Praxis BB or even std. BB30 bearings on a BB30 bike and uses grease to facilitate press of the sleeve or bearings, a small amount of grease is captured between the sleeve or bearings and the BB30 alloy bores inside the BB shell. This thin film of grease is in effect a controlled volume. A captured very slender volume of grease...but in essence this volume of grease isn't truly captured and hence the problem. When applying a lot of pressure the pedals there is a cantilevering of the bearings within the shell. Grease is a fluid and all fluids are incompressible. But the controlled volume isn't truly closed. It is open on the outboard side. With repeated cyclic loading the bearings fractionally toggle within their bores...this is a very minute displacement. This grease film dissipates with repeated cyclic loading because the grease hydraulics out of the outboard gap. In effect the grease is pumped out between the OD of the sleeve or bearing and the I.D. of the 42mm BB30 bore(s). Once the grease is pumped out, the creaking begins.

To mitigate this, simply use Loctite instead of grease. Loctite is a low strength adhesive that hardens and doesn't have the amorphous quality of grease. In effect when it hardens it becomes a spacer filling all the micro voids between sleeve or bearing OD and bore I.D. It can't hydraulic out. Further is stabilizes the sleeve or bearing because of its adhesive quality. If a Praxis sleeve or BB30 bearings are Loctited in place and a crank has proper preload aka wave washer compression or mechanical preload adjusted properly and bearings are good, it can't creak.


The praxis instructions are quite specific to specify antiseize on both the threads and the shell interface.............

http://www.praxiscycles.com/wp-content/uploads/conv_kit_instructions.pdf



The first couple of times I installed the BB I did bit by the book as Praxis instructed, that hasn't worked and I do tend to agree with Highdraw here. Interestingly, Praxis instillation instructions for the BB86 M30 Bearings DO include loctite so it's definitely worth a try! (Even if that is just a bearing and not an expanding collet)

goodboyr
Posts: 1414
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

Agree that FWIW, you may as well try. And if it works, you should feed this back to them so that its incorporated in their docs. I was just responding to highdraws statements about antiseize vs loctite. It would be interesting to hear from praxis about this, both from why they specify anti sieze, and their thoughts on using loctite.

highdraw

by highdraw

goodboyr wrote:
highdraw wrote:Sorry if I disagree with your advice itsacarr. Its isn't the sleeve thats creaking. Putting antiseize on a Praxis collet thread will do nothing other than make it more weather proof and allow getting the Praxis BB apart if left on the bike a long time thru poor weather conditions. The thread is under preload when the Praxis BB is tightened to full lock. Creaking occurs between the O.D. of the Praxis sleeve and the I.D. of the BB30 alloy bores. Some of course place grease or antiseize on this interface to quiet a creak but few understands why it will start creaking after a few weeks.
Basically what you have is a pump. Heresy you say? Its a micro pump. Few understand this dynamic so will explain. When an owner or bike shop installs a Praxis BB or even std. BB30 bearings on a BB30 bike and uses grease to facilitate press of the sleeve or bearings, a small amount of grease is captured between the sleeve or bearings and the BB30 alloy bores inside the BB shell. This thin film of grease is in effect a controlled volume. A captured very slender volume of grease...but in essence this volume of grease isn't truly captured and hence the problem. When applying a lot of pressure the pedals there is a cantilevering of the bearings within the shell. Grease is a fluid and all fluids are incompressible. But the controlled volume isn't truly closed. It is open on the outboard side. With repeated cyclic loading the bearings fractionally toggle within their bores...this is a very minute displacement. This grease film dissipates with repeated cyclic loading because the grease hydraulics out of the outboard gap. In effect the grease is pumped out between the OD of the sleeve or bearing and the I.D. of the 42mm BB30 bore(s). Once the grease is pumped out, the creaking begins.

To mitigate this, simply use Loctite instead of grease. Loctite is a low strength adhesive that hardens and doesn't have the amorphous quality of grease. In effect when it hardens it becomes a spacer filling all the micro voids between sleeve or bearing OD and bore I.D. It can't hydraulic out. Further is stabilizes the sleeve or bearing because of its adhesive quality. If a Praxis sleeve or BB30 bearings are Loctited in place and a crank has proper preload aka wave washer compression or mechanical preload adjusted properly and bearings are good, it can't creak.


The praxis instructions are quite specific to specify antiseize on both the threads and the shell interface.............

http://www.praxiscycles.com/wp-content/uploads/conv_kit_instructions.pdf

I know. Just like many companies spec grease like Trek for Press Fit. A large subset creak depending on tolerance stack.
The dirty truth is, the industry is not uniform in its specification of Loctite. Principle reason is, this specification has consequences for companies like Praxis and Wheel Mfg with their PF30 BB where they equivocate based upon level of interference aka tolerance. Their market research probably suggests lost sales revenue in specing Loctite that many don't want to deal with. Some don't like the idea of using an adhesive to promote a stronger connection. There are fit conditions where grease will work fine based upon build tolerances and even influenced by a the power of a rider. A strong rider plus a high side of tolerance slip fit promotes movement and noise without Loctite. With Loctite, dead quiet.

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CBJ
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by CBJ

I have had little clicks from mine but lately it's fine and seems to work. However I have much better experience with my S-works cranksets on my other bikes.

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Calnago
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by Calnago

@Highdraw: Out of curiosity, how many BB installs that were done with Loctite 609 or other retaining compounds, and primer have you removed, be they BB30 or PF30 or, of most interest to me, your experience with alloy pressfit cups into carbon shells, Chris King in particular. As you note, industry standards in its use are anything but standard, so despite the fact that Chris King specifically recommends against using a retaining compound with their PF30 cups, do you have any experience with them where it was used and how easy was it to get the cups out?
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