Mavic Cosmic Carbone Ultimate issue (cracking sound)

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Imaking20
Posts: 1484
Joined: Fri Nov 18, 2011 5:19 am

by Imaking20

I recently acquired a set of MCCU and upon riding them I immediately learned what all the fuss is about. Then as I got away from the noise of town I started hearing a bit of a rattle - what sounded like something from the front end. I couldn't locate the source off the bike nor was I able to reproduce the sound when shaking or spinning anything.
The next (warmer) day the sound was more frequent and a bit louder. After my ride I put the bike on the stand and applied pressure back-and-forth to the front and rear wheel (think of making the brake pads rub) and there came the noise.
It seems there is a very small amount of movement on one side of the front hub - taking place between the dust/end caps and the hub body. When this movement occurs it emits a fairly loud popping sound. When on the bike, this happens anytime I put moderate weight over the front end or ride on less than outstanding tarmac.
I'm really hoping this tolerance issue does not rest solely with the hub body diameter as it's obviously not really replaceable. My suspicions of this metal to metal clearance being the issue were somewhat confirmed when the noise was barely audible in the morning, then much louder in the afternoon when ambient temperature rose.

My LBS is going to take the hub apart and have a look - most likely ending in a rebuild. My questions is to anyone who may have experienced this before. Any information that people can offer to narrow down my search for a remedy would be greatly appreciated. I head to Colorado this weekend and was very much looking forward to these being the primary wheel!
Current:
T2

Retired:
Blue | Project C6.0 | Felt AR FRD | Colnago C59 NERO | 2014 S-Works Tarmac | S-Works Venge | Wilier Cento Uno SL | Tarmac SL2

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Rappid
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Location: Ireland
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by Rappid

Hi,

Bought these wheels second hand last September, everything was fine till now.
About 2 weeks ago I noticed strange sound coming out from front wheels.
This happens when I'm powering on the climb out of the saddle (moving handlebar left-right, left-right).
My first guess was the bearings got loose but today I want to my LBS and one guy said
that the cracking sound coming out from the place where spoke is melted in hub.
Does anyone here experienced same problem?

Thanks for any help, Seb

by Weenie


MavicZack
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Location: Boulder, CO
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by MavicZack

Hi Seb,
I would start by removing the axle and hub bearings, then grease or anti-seize the surfaces in contact with the hub shell and axle. Sometimes a micro amount of movement between these parts can make a crack or creak noise. This would be the most likely scenario in your case. I would be really surprised if it were the carbon hub shell/spoke interface.

give it a shot with the bearings and let us know!
-z
USA Communications Guy
Mavic, Inc.
http://www.mavic.com
http://www.facebook.com/mavic

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Rappid
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Location: Ireland
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by Rappid

thanks, I will let you know soon!

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mrowkoob
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Location: Middle of nowhere, EU

by mrowkoob

Grease the quick release boltthreads as well. Very common noise source.
The unbearable wallet lightness of being a weightweenie

Imaking20
Posts: 1484
Joined: Fri Nov 18, 2011 5:19 am

by Imaking20

Wtf, I asked this weeks ago and nobody said a peep.
Current:
T2

Retired:
Blue | Project C6.0 | Felt AR FRD | Colnago C59 NERO | 2014 S-Works Tarmac | S-Works Venge | Wilier Cento Uno SL | Tarmac SL2

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Rappid
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Location: Ireland
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by Rappid

Hi MavicZack,
New bearings installed yesterday, unfortunately, problem remains the same :(
Must be something wrong with spoke-collar-hub.
I think I have to ship my wheel to mavic service.
What do you think?
Regards, Seb

Imaking20
Posts: 1484
Joined: Fri Nov 18, 2011 5:19 am

by Imaking20

Yesterday I found the source of my cracking sound in the front hub. When the bearings came out there was material visible in the hub shell - I'd have been satisfied if it was metal from the bearing but it was actually glue/epoxy that bonds the metal cup (which houses the bearings and end caps) to the carbon hub shell.

I did a little digging for bonding agents which aren't likely to harm the carbon and I've come up with Loctite 648 and Scotch-Weld DP460. It seems the latter also requires another additive which may be an issue considering the limited space to work with. I believe the Loctite technically needs a base primer but again - there isn't a way to fully remove the cup in order to prep the surface.


If I can find some Loctite today I'll probably have a got with that this evening. I'll update with any results.
Current:
T2

Retired:
Blue | Project C6.0 | Felt AR FRD | Colnago C59 NERO | 2014 S-Works Tarmac | S-Works Venge | Wilier Cento Uno SL | Tarmac SL2

MavicZack
in the industry
Posts: 82
Joined: Thu Apr 28, 2011 11:40 pm
Location: Boulder, CO
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by MavicZack

Yes I would suggest the loctite 648 for cylindrical parts. I think it will be fine without the base primer but cure time might be higher.

But actually now that you know for certain the issue, this would be an issue that the Mavic MSC shop could fix, if you were to visit a local Mavic dealer and inquire, they should be able to take this under warranty repair. In fact, this is officially what I would suggest as your first step. According to the letter of warranty policy, etc, any attempt to fix or modify could potentially void the existing warranty and cause probs for the MSC to fix it properly in the future.

don't hesitate to send a pM if you need additional advice - z
USA Communications Guy
Mavic, Inc.
http://www.mavic.com
http://www.facebook.com/mavic

duodiscus
Posts: 25
Joined: Wed May 30, 2012 4:33 am

by duodiscus

Slightly OT, but a question for MavicZack: could you give us an idea when Mavic might approve use of SwissStop Black Prince brake pads on Cosmic Carbone Ultimate wheels? From tests and feedback it seems that the Black Prince pads are superior to the Yellow King pads that we're required to use on CCUs to keep the Mavic warranty intact.

Thanks!

Imaking20
Posts: 1484
Joined: Fri Nov 18, 2011 5:19 am

by Imaking20

Problem solved. Here's what I did:

Remove front hub caps and bearings.
There will likely be material floating around in the hub which SHOULD just be the glue that came loose to cause the cracking sound. Clean everything up as best you can.
Apply a small amount of LOCTITE 648 just behind the little black cup in the hub. There will be a slight edge where it transitions to carbon, I put a few drops behind the edge, tilted the wheel a bit and slowly rotated the wheel until I saw the bead of Loctite disappear. I repeated this process until I couldn't get any more loctite to seep down between the hub and cup and wiped off the excess.
I then laid the wheel on a flat surface with that side down to allow the loctite to setup (which it does fairly quickly).
An hour or so later I repeated the process.
Let sit overnight.

Put the hub back together!

I just got back from a ride that would have caused the wheel to make copious amounts of noise before and I didn't hear a peep.
Current:
T2

Retired:
Blue | Project C6.0 | Felt AR FRD | Colnago C59 NERO | 2014 S-Works Tarmac | S-Works Venge | Wilier Cento Uno SL | Tarmac SL2

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Rappid
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by Rappid

Imaking20, thanks a million.
Will do the same and let you know.
Cheers!

MavicZack
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by MavicZack

HI guys, sorry for the delay. I have an answer for duodiscus above:
We are currently testing the new Black Prince pad to make sure it does not damage the wheel.
Till those tests are completed, we cannot say using them will not void the warranty.

So far, performance seems to be only slightly better than our yellow one, but it wears out quicker.
As for rim durability, this requires much more time on many sample in real life conditions, so we don’t have the official green light yet.

there you go! thanks for your interest in Mavic - zack
USA Communications Guy
Mavic, Inc.
http://www.mavic.com
http://www.facebook.com/mavic

duodiscus
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Joined: Wed May 30, 2012 4:33 am

by duodiscus

Thanks very much Zack!

by Weenie


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Rappid
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Joined: Thu Sep 11, 2008 1:24 pm
Location: Ireland
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by Rappid

Bought epoxy resin and hardener.
All sorted, no more cracking sound after applying the adhesive.
Jejeje! :)

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