D@MN!
Consider yourself very lucky you got away without injury.
There are 2 possibility's:

- you are extremely powerfull or;
- the carbon is very very sloppy.

I'd say it's the second one

grtz

It's just careless use of material. The testers for this crank are the consumers. There needs to be a change in design here....it should have happened a long time ago.

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This board and the world in general would be a much nicer place if everyone could just take themselves a little less seriously.

Campagnolo cranks use full carbon tabs and don't suffer from this issue. They are on the other hand constructed with more material. I think proper assembly also plays an important role. When bolts aren't sufficiently tight most of the shear load is transferred directly from bolt to tab and not shared between the clamping force of chain ring and crank tabs.

Then I guess Stronglight needs to take some notes from Campy if they are going to continue to manufacture these with full carbon.

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This board and the world in general would be a much nicer place if everyone could just take themselves a little less seriously.

Iv'e been watching this thread and other Pulsion failure posts with interest. Had Pulsion CT2's on my TCR for about a year with no problems. My immediate thought after seeing the failure pics here was loose chainring bolts. Finally checked mine yesterday. They were not flopping loose but certainly not sufficiently tight; easily tightened all bolts 3/4 turn or more. It would be a good idea for all who ride Pulsions or ASX cranks to check their chainring bolts.

I've been a serious lurker here for the last 2 or 3 years. This issue finally moved me to become a member and add my 2 cents worth.
I've learned much on this board. Thanks to all who participate and make it happen.

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"You can't get there from here"

IMHO this is not a manufacturing issue, it is a design issue.
Everyone complains about campy chainring bolts for carbon cranks being non-standard in size; well, after having seen all these failures the reason appears to be quite obvious: they use a smaller chainring bolt so the hole in the crank tab is smaller and the tab is stronger.
I bet in a few months all these cranks will adopt the campy size chainring bolts...

Still waiting on my replacements..... InterBike slows EVERYTHING down

But, the shop that sold me the cranks went ahead and ordered a replacemnet set (since QBP only had 1 set in stock) and said they'll work out the detials of the swap on their own. That's pretty decent service if you ask me.

I really hope I just got a hold of a bad crank. There are lots of these in service and only a handful of failures reported. Of course, the Zerogravity crankset is coming out in a couple months I have a serious feeling one of those will end up on my bike.

Briscoe,

To give you some good news, I've had two sets of the titans and I've had zero issues. The are solid, stuff and just plain work. I do check the crankbolts pretty often but I do that on all my cranks. Good luck on your next set.

JB

Anybody know the correct amount of torque on the chainring bolts before you start to impact the carbon and create the failure yourself? hhhhhhhhhhmmmmmmmm

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MyGiant! MyScalpel!
".....but our amps go to eleven"

THM spec 5nm for the chainring bolts on Claviculas.

So my new cranks arrived today!!! Not too bad really. They shipped outlast night at 6:30pm... I had them in my hand at 8am this morning. Now, I just have to decide if I should give them another chance... or sell these puppies and buy something else.

I'm leaning to give them another shot. There are quite a number of these cranks out in the market with only a couple failures in this way. I'd like some Record cranks..... but just not sure I want to hassle of selling these. Plus, I'm quite sure I will have to buy some Zero gravity cranks when (if) they actually hit the streets.


That being said... if anyone wants some ASX Titan cranks.... drop me a PM

I thought it had only happened to my Pulsion but I read a pair of topics which left me in shock.
My replacement crankset is on its way (I guess it's the horrendous X-Wing) but I am not confident about its quality...
What crankset would you advise, considering that I am trying to get my bike under 6 kg and I need light material? (Either way, I prefer a heavier set than being thrown off my bike because of lousy material failure...)

Some pictures of the results:









Sure they are light... But Strong?!

^ that sucks, but if you're going to push for nothing but light weight, be prepared for more of this.

This is unacceptable risk for the sake of weenieism. One could get killed from a failure like that.

You'll have to pry my cheap, heavy aluminum crank from my cold, dead hands.

Well, for the price one pays for material like this (around 700€), very good quality was to be expected.
Yes, they are light but from an experienced brand, which would never make me suspect of the probability of a think like this actually happen. If technology does not yet allow the safe production of carbon spiders they should not be on the market; if they are, I assumed they had been fully tested, all situations and possible failures equationed, and yes, I did trust Stronglight.

I would never put weight-saving before my own safety; ever! So, for as much as you hate carbon stuff, your words are nothing but unfair and bitter.

I could not agree more.

I am all for light weight parts, and advancements in technology. However, I am currently staying away from carbon Cranks, Stems, and Bars. I have a collection of broken carbon stems and bars, I am 6' tall and 155lbs. Not a big guy by any means. Thankfully I have not been hurt in these failures. My new Time Trial bike is going to come with a Carbon crank with an aluminum spider. I thinking about getting a dura ace crank set for it.

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2011 Specialized S-Works Tarmac SL3 (If the insurance allows)
2010 Specialized Tarmac Pro
2008 Custom Columbus XLR8R Frame (Team Branded)
2006 Specialized S-Works E5 Aerotec - Stolen
1995 Pinarello Stelvio (Fixed Gear)