# Anyone else had a problem with carbon steerer failure?



## Balderick (Jul 11, 2006)

I have a bike - I will not mention the brand, but it is American designed and probably constructed in Asia somewhere. High modulus carbon is used in the frame and carbon steerer fork. I like the frame and the fork.

I had a problem with the carbon steerer, where there seemed that the inside front face of the stem had worn away the outer surface of the steerer. The fork/frame importer looked at, and said it was safe but to keep monitoring monthly. I had the bike shop check it at least monthly, for I am a large (100+ kg) and strong rider, and one of the courses I race at has rough patches that are probably close to pave'. The LBS reported no problem, and swapped out the stem so the contact spots were different.

I raced last Sunday on the aforementioned course. The front end of the bike felt fine riding to racing, and during racing, and I did not hit anything unusual during the race. However, on the ride home from racing I thought the front end felt "soft" - I then twisted the bars forward and they moved. Showed it to a friend, who owns another LBS, and he said ride it carefully back to his shop. His mechanic stripped it down and the carbon steerer looked like it had delaminated around where the stem had been fitted.

The LBS that sold the bike has a very good mechanic, and i have no doubt he did all that was required - he is a torque wrench kind of guy. The forks is being sent back to the importer, and I expect it will be covered under warranty. I am still mobile, as I have been lent a Chromo-moly fork which is much better than I thought it would be.

That background given, my question is whether others have experienced this kind of delamination, or failure, of carbin steerer. I get kind of nervous with carbon steerers. Do I ask for a cheaper fork with an Al steerer, but then I think that the binding between the Al steerer and fork crown becomes the weak link?


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## justsomeotherdude (Jun 1, 2004)

I have to ask....did they grease the carbon steerer at the stem? The only things I have seen cause a delam is excessive heat(heat gun), grease and a small crack that spread.


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## pmseattle (Dec 9, 2004)

Last year I witnessed a spectacular carbon fiber steerer failure which I believe may have been caused by a too-heavy rider on an OCLV. The steerer abruptly snapped apart just above the fork crown, smashing the rider face-first into the pavement. He was seriously injured and had to be hauled away by the EMTs. I took photos . . .


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## Applesauce (Aug 4, 2007)

Surprised this hasn't come up yet... Hincapie demonstrated for the world "the safety of an aluminum steerer" (or whatever tag-line Trek used to attach to it). Hincapie's fork did not break at the crown's bonded junction; it snapped at or above the top race. I won't conflate correlation and causation, but Trek has since started offering all-carbon forks, and plenty of very big guys ride Treks (and similar brands). Part of cycling, I think, is being comfortable with the fact that _anything_ you're riding could, at _any_ time, fail, catastrophically or otherwise. Some things are less likely to fail than others, though, and I think that's what you're asking... But I can't offer much advice. I weigh 150 lbs and ride a steel frame and fork. (But it, too, could fail at any time.) Take Magnus Backstedt, for instance: why wasn't he just breaking stuff left, right, and center? Smart choices, partly, but surely partly just luck - and good mechanics - too. (Speaking of mechanics, I won't blame yours, but I will say you shouldn't exonerate him completely.)

If I were you, I would not chalk it up to materials. First, I would call it a fluke. (Well, _first_ I would be thankful it didn't leave you hurt, badly or otherwise.) Second, I would see what the manufacturer returns to you under warranty. Does it look _exactly_ the same? If so, that could indicate a) your first one was a fluke and you couldn't have seen (or foreseen) the cause of the failure or b) your second one will fail just like the first, which would be a surprising and stupid - though not unprecedented - chance for the manufacturer to take. If not, they're tacitly acknowledging the problem and hoping nobody dies; but in any case, they're replacing your fork with one that they have deemed less likely to get them sued to nudity. Third, taking all that into account, I would considering going with a fork from a more reputable (though that's hard to say, given that you're justifiably not broadcasting the manufacturer) maker; I've never seen a Reynolds fail (without being crashed, of course), and I've seen them under bigger guys than you. Wound Up and Alpha-Q also make some very, very sturdy models; I have had the steerer (also at the stem, like yours) and bonded aluminum dropout faces delaminate on a Ritchey WCS fork (don't ask how I noticed both at once).

All that aside, I think the neutrality with which you're approaching the issue is great, and certainly refreshing on this forum...


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## Balderick (Jul 11, 2006)

justsomeotherdude said:


> I have to ask....did they grease the carbon steerer at the stem? The only things I have seen cause a delam is excessive heat(heat gun), grease and a small crack that spread.


I have seen no evidence that grease was applied at all, and I'd be surprised. If the guy who built the bike used anything he would have used that Ritchey carbon grippy stuff.


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## Kerry Irons (Feb 25, 2002)

*Not likely grease*



justsomeotherdude said:


> I have to ask....did they grease the carbon steerer at the stem? The only things I have seen cause a delam is excessive heat(heat gun), grease and a small crack that spread.


There are all kinds of CF parts that are continuously exposed to grease (derailleurs, brake levers) and they suffer no ill effects. While the "no grease" mantra is repeated constantly on the Internet, the only problem with grease is if it cause your stem, bars, or seat post to slip. Not an issue for damaging parts.


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## tom_h (May 6, 2008)

Balderick said:


> ...
> I had a problem with the carbon steerer, where there seemed that the inside front face of the stem had worn away the outer surface of the steerer. ..


Curious , is the inside of your stem smooth, deburred, and free of sharp edges or ridges? I can imagine that such ridges might act like a sharp knife on the steerer tube, over time, scraping away outer layers of the composite. 

FWIW, Specialized posts the following "caution" on their framset/fork assembly. I think it's a bit overkill, and may be self-serving ... since AFAIK Specialized is the only stem I've see with a continuous coverage shim surrounding the carbon steerer :

_... Specialized recommends against the use of stems with large bore holes_
_in contact with the steerer tube. Large bore holes reduce the surface_
_area and concentrate the load onto the carbon steerer tube...._

_... __The continuous or near-continuous surface area of Specialized stems provides a very high amount of surface area contact with the steerer tube, which helps __to evenly distribute loads...._ ​
​


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## Kuma601 (Jan 22, 2004)

IDK if we'll see an ideal stem and fork interface when lightweight is a factor. Specialized tech bulletin does raise some interesting thoughts into stem design. I like what Easton has integrated into their '09 forks with ITT. http://www.eastonbike.com/PRODUCTS/FORKS/fork__top.html

Maybe a re-enforcing sleeve like what Giant has in their Alliance series frames for higher stress and or weight categories. Scary to think about any failure regardless of materials.


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## PlatyPius (Feb 1, 2009)

Kuma601 said:


> IDK if we'll see an ideal stem and fork interface when lightweight is a factor. Specialized tech bulletin does raise some interesting thoughts into stem design. I like what Easton has integrated into their '09 forks with ITT. http://www.eastonbike.com/PRODUCTS/FORKS/fork__top.html
> 
> Maybe a re-enforcing sleeve like what Giant has in their Alliance series frames for higher stress and or weight categories. Scary to think about any failure regardless of materials.


Being a lard-arse, I decided, upon seeing the new Easton forks that the rep was pimping, that I would be riding Easton forks from now on. They still weigh next to nothing, but they look beefy. I've always been somewhat afraid of a steerer tube failure; especially after seeing the Wolf SL forks that we replaced last year.

And, I gotta say..... the glue-in threaded insert things that a lot of forks use are about the stupidest, cheesiest things I've ever seen. This system by Easton makes much more sense.


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## Balderick (Jul 11, 2006)

tom_h said:


> Curious , is the inside of your stem smooth, deburred, and free of sharp edges or ridges? I can imagine that such ridges might act like a sharp knife on the steerer tube, over time, scraping away outer layers of the composite.


The first stem did have a sharp edge, but would not call it burred. The hypothesis was that the wearing on the front side of the sterrer had been caused by the harp edges on the "front" side of the stem. So tThe LBS owner and I went through a whole box of new stems - most very much high end - and all had different degrees of burring and sharpness. In the end the Stem selected - a 3T stem - had more material on that critical interface. No, the LBS did not sell Specialized stems.

While I think the hypothesis was correct, the delamination on the rear and side of the stem suggests to me that the underlying problem is that the steerer was failing along the main point where it was stressed, being the interface with the stem. It failed first on the front because there was greater force per area on that front part of the steerer, as the stem was made lighter.

I can see some real sense in the Specialized system. To me it makes a lot of sense to have a larger contact area of a stem binding to a carbon steerer.

Might not make a whole lot of difference when the roads are smooth or the rider weighs less than 80 kg. However, for a larger rider like me I will take a reliable part over a lightweight one. Last thing I want to happen is for the stem to fail. I had a lightweight alloy bar snap in the early '80s, at 60 kph, and I doubt I would "bounce" as well now as I did then.

Another potential issue was the steerer plug used. I will be insisting on the use of a better/longer/thicker plug.

I am not angling to scam a new fork out of the importer. If it is a warranty issue and they give me a new fork then that is great. However, ultimately I am more than happy to buy a compatible safe sturdy fork.

As an aside, the CrMO fork my LBS owning mate (not the shop I bought the subject bike from, although both are mates) has lent to me is a real trip back to the days when I had a 6 pack stomach, was too young to drive a car and steel was not just real, it was all mere mortals could afford. I raced a crit yesterday and the fork, bolted (securely) to a still HM carbon frame felt a bit "out of sync" on the tighter corners, almost like it was less dampened. It was a tight course with three 180 degree turnarounds, anda host of faster 90 degree turns. It was quite nice throught he faster corners, but felt :Wrong" when coming hard under brakes in to a 180 turn.

Overall this fork is nice (but oh so heavy) but has a less dialed in feel to the forks that they are replacing. But I think this fork - I think it is off a track bike - is unlikely to break, or if it does it will bend first.


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## tom_h (May 6, 2008)

*3t*

I've read other favorable comments regarding the good finish on the inside of the 3T stems.


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## kiwisimon (Oct 30, 2002)

Hope the rider got better soon. plus one Applesauce.


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## -dustin (Jan 11, 2009)

pmseattle said:


> Last year I witnessed a spectacular carbon fiber steerer failure which I believe may have been caused by a too-heavy rider on an OCLV. The steerer abruptly snapped apart just above the fork crown, smashing the rider face-first into the pavement. He was seriously injured and had to be hauled away by the EMTs. I took photos . . .


How on earth does that happen? What did Trek have to say about that?


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## PlatyPius (Feb 1, 2009)

-dustin said:


> How on earth does that happen?


Magic, apparently. A whole bunch of people here on RBR will expound upon the virtues of carbon and how it never fails and will last forever.

Always remember kids, carbon does NOT explode!


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## nightfend (Mar 15, 2009)

I've noticed that Colnago has a 90kg rider limit for their frames and forks and they overbuild their carbon steerer tubes. So I think weighing over 200+ doesn't help the situation.

That said, you just never know... as was mentioned, the famous Hincapie crash was caused by an aluminum steerer tube failing on his fork.


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## Applesauce (Aug 4, 2007)

Balderick said:


> ...It was quite nice throught he faster corners, but felt :Wrong" when coming hard under brakes in to a 180 turn.
> 
> Overall this fork is nice (but oh so heavy) but has a less dialed in feel to the forks that they are replacing. But I think this fork - I think it is off a track bike - is unlikely to break, or if it does it will bend first.


Most likely it's not a question of "damping" that could be traced to materials, etc.; most likely, the geometry of the fork is not compatible with that of the frame, i.e., the latter was not designed for use with the former. This is something you should consider (i.e., measure) carefully if you go for an aftermarket fork.


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## il sogno (Jul 15, 2002)

Do you have a Giant? They had a fork recall recently. 

http://forums.roadbikereview.com/showthread.php?t=159600&highlight=fork+recall


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## Sherpa23 (Nov 5, 2001)

I have a Reynolds Ouzo track fork with a cracked steerer. I used it for a whole season and it was fine, and then I broke it on an indoor track. I have been switching to Edge forks, anyway. Still, it's disappointing as I really like Reynolds products.


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## Balderick (Jul 11, 2006)

nightfend said:


> I've noticed that Colnago has a 90kg rider limit for their frames and forks and they overbuild their carbon steerer tubes. So I think weighing over 200+ doesn't help the situation..


I do weigh over 90 kg - but thankfully not over 200kg! Heaviest I weighed was 123kg, and lightest in the "post children" phase of life was 95 kg.

I am always mindful that manufacturers will design a bike to suit riders under 80 or 90 kg, and might be driven by market forces to put bikes out there that are lighter than my needs might require. Hence the bike in questions was selected because it was designed to be for larger stronger riders - that is, for sprinters rather than pure climbers.



> Do you have a Giant? They had a fork recall recently.


I do, an 03 TCR composite with an Al steerer. It has done 40,000 k of riding, including the time when I was 123 kg, and never missed a beat. It is, however, a bit of noodle c/f the current bike, which is a very nice stiff frame. I rode the Giant last week and I swear that with a Ultegra rear wheel (I( usually ride a 32 spoke CXP33) it felt like an old Proflex MTB!

A number of my friends have the Giant bikes subject of the fork recall. None of their returned forks had any cracks or other external signs of failure. Good to see a manufacturer taking a conservative, and no doubt expensive, approach to this. But then, they sell a lot of bikes in litigation prone countries like the USA and Australia, so caution is probably also sound business.

I read with some concernt hat some people have ridden on forks they knew to have a crack. In my (law) firm we have acted for people that were severly injured when their forks (in each case on a MTB) failed, and in each case they were riding slowly and were riding on a piece of junk purchased from a supermarket. My respectful point is not to avoid riding poorly designed and manufatured bikes - most on this forum know that - but that the consequences of a fork failure can be serious at low speed, and horrific at the higher speeds we all tend to ride at on road bike. Not intended to flame those who have done it - we are all adults able to make our own decisions - but just urging people to be careful.


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## tom_h (May 6, 2008)

As an aside, Specialized -- and possibly other Mfrs too -- uses carbon steerers that oversized at the bottom of the steerer (IIRC, 1.50") and tapering to the standard 1.125" at the top.

While this makes for a proprietary fork design, it increases strength against the type of failure depicted in post # 3 -- for a constant wall thickness, large diameter tubes are stronger.

Offhand, I don't know when Spec'y started with the oversized steerers -- my 2009 Tarmac has one.


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## nightfend (Mar 15, 2009)

I'd look at the tandem carbon forks out there. Alpha Q has a Zpro fork made for tall and large riders that is basically a rebranded tandem fork with a slightly altered rake. Yes, it is 500 grams, roughyl 200 grams more than a typical carbon race fork weighs, but it would at least give you peace of mind to know your steerer tube isn't going to crack. Wound-up also makes a large rider/tandem fork.


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## Balderick (Jul 11, 2006)

An update. 

The importer claims to have tested the forks and found no fault. It has, however, provided a set of replacement forks (which I will have fitted today) to see if the problem is fixed, but there was a suggestion that if the problem persists it may be a problem with the frame. I doubt the problem is with the frame, as I have been riding it with a set of CrMo forks and all of the flexing that caused me concern has disappeared. I am told the replacement forks are not new but look to be in good condition - in any event they will probably have had less use than the faulty forks. However, I know those faulty forks have not been crashed...

I will ask the LBS owner - who weighs slightly less than me but is a more powerful rider, to ride my bike with the current CrMo forks, and then with the new forks. He also rode my bike with the faulty forks a week before the problem arose and then after, and he was of the view the forks were failing.

So, it seems the importer is providing a solution. If those forks still feel suspect then I will probably pay for an alternate non OEM fork.


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## stevesbike (Jun 3, 2002)

You're not asking a very specific question - there's nothing wrong with carbon as a material for fork steerer tubes. People get carried away with anecdotal accounts, ignore base rates, etc. If your firm is litigating these sorts of cases, you know that the burden is to show some statistical evidence of a systematic failure of the product - an isolated event or two doesn't do that.

You are sending your LBS on a wild goose chase - test riding the forks isn't going to reveal a 'suspicious feeling.' You don't understand the failure mode of a fork - you won't feel a failure in the making - it will typically be undetectable until it actually fails (which is referred to as a catastrophic failure).


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## tom_h (May 6, 2008)

stevesbike said:


> ...You are sending your LBS on a wild goose chase - test riding the forks isn't going to reveal a 'suspicious feeling.' You don't understand the failure mode of a fork - you won't feel a failure in the making - it will typically be undetectable until it actually fails (which is referred to as a catastrophic failure).


Yes ... extreme differences in flexibility between different _models_ of CF might be discernable, but won't be indicative of reliability or strength.

I recall seeing a video clip of a CF fork being QA tested -- might have been at Look Cycle. They had the fork steerer clamped rigidly, and pneumatic cylinders cyclically applying displacement to the bottom tips of the fork. This was bending the CF fork something like 1/2" backward, 1-2 times per second. 

They said this cyclic stressing went on for many 100s of thousands of cycles without failure. Test was finally terminated, still without fork failure. The implication being, this is the typical strength of a CF fork, provided it has no manufacturing defects.


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## Balderick (Jul 11, 2006)

stevesbike said:


> You're not asking a very specific question - there's nothing wrong with carbon as a material for fork steerer tubes. People get carried away with anecdotal accounts, ignore base rates, etc. If your firm is litigating these sorts of cases, you know that the burden is to show some statistical evidence of a systematic failure of the product - an isolated event or two doesn't do that.
> 
> You are sending your LBS on a wild goose chase - test riding the forks isn't going to reveal a 'suspicious feeling.' You don't understand the failure mode of a fork - you won't feel a failure in the making - it will typically be undetectable until it actually fails (which is referred to as a catastrophic failure).


No - if I were litigating, and I am not, I need only prove that *my* fork failed and the failure was due to a design or manufacturing fault. I know it is not commercially viable for me to litgate, due to the cost of securing the evidence I would need as the only loss I have (luckily) sustained is the value of the forks. However, had I suffered serious injury (as some of my firm's clients have) then the cost of doing the testing of the forks to secure that evidence is easy to justify.

I think I did detect the failure of my fork. It went from being stiff and precise to being soft and noodly over a short period of time. The replacement fork feels just like the broken one before it broke. I accept that I was probably fortunate that I had to stop. My LBS owner felt the same change.


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## stevesbike (Jun 3, 2002)

In over 25 years of being around a lot of bikes, I've never heard of a single case of a detectable fork issue like this - now you say the second fork is the same way. I'd like to see a pic or two. You are saying that the second fork has the same detectable problem - that there's enough play in the stem/fork interface to effect handling?


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## Balderick (Jul 11, 2006)

stevesbike,

Likewise - I have been around bikes well over 25 years, and I had not experienced anything like this before. But then every bike I have had prior to this had a Al or Fe steerer, or had Fe quill stems. That may be a coincidence. 

I have never had a headset fail on a bike, and that is despite riding is all weather. Not sure if that tells you that I am not a person terribly hard on my bikes. I know a few much lighter riders who seem to trash headsets fairly frequently, but then they don't bend pedals or pull spokes like I do.

I did not mean to say that the replacement fork has also failed. What I meant to say is the replacement fork is as rigid as the original fork was before the original fork failed. I raced on it (the replacement fork) on the weekend (on that same dreadful course - 70k race), have trained on it, and rode to work on it this morning. In the 300 or so km I have done on it - and that includes a wide variety of road surfaces and effort - it seems to be working just fine.

I did not take photos before I took the bike in to the LBS, or when I was at the LBS to collect my frame _sans_ fork, simply because I never had any desire to litigate. As stated, if the importer did not provide a replacement fork I would simply have purchased a suitable replacement fork - the cost of a new fork is small compared with the time and cost of proceedings. 

The importer now has the original fork. I doubt they will provide the fork to me so I can take pictures of it to post on the 'net.

For me, what it means is I will be quite careful to inspect the carbon steerer on my bike, and will purchase a torque wrench so that I can take the stem on and off during normal maintenance. To date I have not touched the stem and if it needed regreasing I would take it to the LBS, simply because I did not have a torque wrench to re-tighten the stem.


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## Mr. Versatile (Nov 24, 2005)

OK, get the flame throwers fired up. 

I raced from 1960 through 1987 or so. In all that time, racing, riding, touring, running errands, commuting, etc. not once, not ever, not under any circumstances have I seen threads like this where something so structurally vital failed. All right, I do remember a few stem failures, and I also remember a guy in our club breaking a chain stay on a Serotta. He shifted the derailleur into the spokes, it rotated around and mashed the stay. 

This makes me wonder about plastic bikes. Look how many questions and concerns pop up on this forum about them. Does grease hurt them; how do you paint them; I weigh xxx#. Am I too heavy for a CF bike; if I use solvent on my chain and some of it accidentally spills on my CF frame, will it be damaged; how do I clean them; is this crack significant; do you think the mfg will warranty this; where can I get this repaired; if I get it repaired will it be safe to ride; how much torque should be applied to the stem, bars, cranks, pedals, etc.; I'm hearing this noise from my CF frame, is it safe to ride; I crashed my CF bike. It looks like there's no damage, but I need to know if it's safe to ride; is it harmful to ride my CF frame in the rain; what kind of wax should I use to polish my CF frame; can I trust my CF frame on 40+mph bumpy downhills; can I put a trunk rack on my CF bike; can I put a trunk rack on my CF bike if it has a CF seatpost; will CF crack if I leave it outside in freezing weather; will my CF bike hold up to the stress of poorly paved, potholed roads; how long should I ride a CF frame before buying a new one; can they fix it if I need to replace a dropout? This goes on, and on, and on. 

I very seldom, if ever, hear questions about steel, aluminum, or titanium bikes. (Yes, I know there's a thread about steel fatiguing). It seems that many owners and potential owners of CF bikes have real confidence issues about using this material on a bicycle.

I apologize in advance if this is untrue, but don't you think that a complete novice that has never even heard of bicycles, would draw some kind of conclusion from these posts? I know that I have and I am hardly a novice. I really try hard not to be a retro-grouch. That being said, If I were looking for a new bike now, a bike with a CF frame or fork would really give me pause. You could say that the same questions were asked about steel and aluminum when they first came into use, but you'd be wrong. "Well, after all, CF is a pretty new product and has a few unknowns, so..." Why are they risking people's lives with it then? Yes, yes, I know it's used for wings on military aircraft. Seems to me they've had some catastrophic failures too. 

Sorry about my doubts, but my doubts are real, at least to me.


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## tom_h (May 6, 2008)

Carbon fiber is less tolerant of _abuse_, than steel, IMO.

If I was building a commuter or touring bike, I'd likely go steel. 

For the weekend, thrill-ride bike, I'm building up a "plastic" frameset ;-)

There's a place for both, just as there is with cars. 

My daily driver is a Chevy K1500 SUV, with a pushrod V8 that rarely turns over 3500 rpm, still runs great after 200K miles, and will still be running great, when all the wiener-green-wanker-mobiles, government-approved by the Obama administration, have 10,000 dead NiMh battery cells ;-)

My "fun" car is an '87 Grand National w/ 20 psi of turbocharged & intercooled boost  Would I drive that on a 1000 mile family vacation? No Way !!


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## Balderick (Jul 11, 2006)

Mr V,

You pretty much hit how I now feel. I have doubts - not doubts when I am riding, but doubts when I have time to think. I thankfully do not think about a fork or frame collapsing at 90 kph, otherwise I would not be riding about 5 kph.

I have had steel, Al, Ti and CF bikes. I have cracked steel, Al and Ti frames, always where there was a weld. All bar one was replaced under warranty, and the one that was not was abused by a stupid 12 year old (me!) who thought road bikes were made to race through the bush. But each of those failures was telegraphed to me long before it became a safety issue - stange noises, flexy frame etc etc.

Neither of the CF frames I currently own has caused me any concern at all. Only the CF steerer subject of this thread. So until now I have no real cause to complain about CF as a material.

What does concern me is I do not have the same confidence in CF as I have in metal bikes - I am concerned that the failure of a component might be sudden. Perhaps that is a concern that is one I should not have, but when you are a larger person you have to wonder whether the quest for light weight means some of the margin for engineering and safety is taken out.

I appreciate the concern I now have is not necessarily based on sound analysis, but it is how I feel.

Mind you, I had the same concerns with lightweight Al bars back in the early 1980s. See, I had a well known Italian brand bar that snapped at 60kph, and it was a crash that hurt quite a lot. However, I now prefer to ride with sturdy Al bars, on my road bikes and my track bike, because I accept they have learnt a thing or two about Al in the past 20 odd years.




What concerns me with CF is


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## Balderick (Jul 11, 2006)

An update.

The importer claimed that they could find no fault with my fork, but provided me with a used replacement which was fitted to my frame by the LBS. The LBS owner remains of the view the fork had failed (in the sense it was flexing too much, not that it had broken). For a few weeks it was fine - nice and stiff , just as the original fork had been. However, the replacement has now developed a similar flexing issue, although not to anything like the same extent as the original fork. There is also a stange knocking noise that seems to somehow be related to the flexing issue.

I thought it was me imagining the flex, although the knocking noise is audible to others and can be felt when pressure is put on the bars. So I asked a number of friends (all long term bike industry people) to see what they thought was the knocking noise, and in the process of moving anf flexing the bars they all noticed the flexing as well. Some expressed the view they would not ride the bike.

I know nothing of the hostory of the replacement fork - it seems (from some residual adhesive from team stickers) to have been used by a local pro team, so I can assume it has had some use. There is no visible evidence the fork has ever been crashed.

Possibly a problem with this brand of forks? Do not know. What I do know is that a friend who was until a pro with the local pro team referred to above (he has now moved up to another pro team) said he found the bike supplied by that team (the same brand as my bike) "went soft".

My LBS guy has suggested I might be better to fit a fork with an aluminium steerer, which I will now do and am looking at an EA70 fork. The original fork really owes me nothing, and when I sell the bike the new owner will be told of the issue and given the option of buying the bike with both forks.

Thank you to those who posted. Even if I did not agree with some of you, I welcome the input.



My cycling fri


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## nightfend (Mar 15, 2009)

I wouldn't recommend the Easton fork. They are pretty flexy. And since that is one of the issues that concerns you, I'd look at other brands. Alpha Q's are very good. Edge and 3T are two other good fork manufacturers.


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## DaveG (Feb 4, 2004)

*good post*



Mr. Versatile said:


> OK, get the flame throwers fired up.
> 
> I raced from 1960 through 1987 or so. In all that time, racing, riding, touring, running errands, commuting, etc. not once, not ever, not under any circumstances have I seen threads like this where something so structurally vital failed. All right, I do remember a few stem failures, and I also remember a guy in our club breaking a chain stay on a Serotta. He shifted the derailleur into the spokes, it rotated around and mashed the stay.
> 
> ...


I think you have pretty much covered every CF concern post in the last 10 years! I built up my first CF bike recently after riding steel for 10 years or so. I have to admit that just reading the lawyer warnings on just about every manufactuers instruction sheet gives me pause. I am not scared that it will explode on me but I will probably inspect it more closely and more often than I do my steel bikes.


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## Steve-a-Reno (Aug 15, 2003)

I don't mean to insult you or the mechanics) but are you sure your headset is installed properly? Are you running a CK or a different type that uses a compression ring to take up slack between the steerer and upper bearing like in the attachment?

This recently happened to me on my MTB. I had CK's for ever and this new one that came on the bike had no compression ring and rode like crap. Steering was terrible and the top cap had to be tightened too much before the play went away from the front end. Luckilly I only took a few slow speed pavement spins through the neighborhood before contacting FSA to get it all straightened out. No harm to my frame, fork or headset and it felt perfect after the compression ring was installed. Heck I never knew I needed a compression ring before.

Just thought I'd throw it out there.
Be safe.


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## longcat (Nov 8, 2008)

Mr. Versatile said:


> plastic bikes.


This is why I'm not even remotely interested in carbon bikes, I dont have time to go through a checklist like a pilot just to make sure the bike is safe to ride. Aaaand I dont trust the workmanship so I would never be able to trust the bike, sure if boeing started making bikes I would trust it.


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## holy cromoly (Nov 9, 2008)

Balderick said:


> ...
> My LBS guy has suggested I might be better to fit a fork with an aluminium steerer, which I will now do and am looking at an EA70 fork...


Also take a look at Wound Up forks. 
They are pricier than many carbon forks, but they have a reputation for reliability and their burliness.

Go with the most reputable quality one you can afford.

Don't want to the be one of these two people who crashed on their REI Novara bikes because of carbon fork/steere separation leading to face injuries.


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## holy cromoly (Nov 9, 2008)

longcat said:


> This is why I'm not even remotely interested in carbon bikes, I dont have time to go through a checklist like a pilot just to make sure the bike is safe to ride...


I am a steel guy, but have carbon bike too. 
The tricky thing about doing a "pre-flight" check on carbon is that there are some parts that simply cannot be inspected pre-ride, a carbon steerer being one of them. For this reason, I've gone with frame/fork set that has an aluminum steerer. 

I think for regular daily riders like us in the real world, an aluminum steerer and fork dropouts are best. Not sure I can trust those Scott carbon fork dropouts.


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## rook (Apr 5, 2009)

*Never buy a Chris King headset if you have a fork that has a carbon steerer*

George Hincapie broke a carbon steerer in Paris-Roubaix once because of the threadless Chris King headset he was using. The design on the top cap of the Chris King is actually quite poor for such an expensive and long-lasting headset. It will make a scoring mark in your steerer every time. Guaranteed. Repeated cycles of hard riding will eventually turn that scoring mark into a crack. And then, fork steerer failure!


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## CleavesF (Dec 31, 2007)

In light of a slight modification of a George Box quote:

"All bike parts are wrong. Some bike parts are useful."


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## otiebob (Jun 25, 2002)

rook said:


> George Hincapie broke a carbon steerer in Paris-Roubaix once because of the threadless Chris King headset he was using. The design on the top cap of the Chris King is actually quite poor for such an expensive and long-lasting headset. It will make a scoring mark in your steerer every time. Guaranteed. Repeated cycles of hard riding will eventually turn that scoring mark into a crack. And then, fork steerer failure!


Bollocks. In the incident you're referring to, he was riding an aluminum-steerer fork. In fact, much was made about the rationale his mechanic had for it in that he thought it would be more robust than a carbon steerer on the cobbles. Look it up.


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## holy cromoly (Nov 9, 2008)

otiebob said:


> Bollocks. In the incident you're referring to, he was riding an aluminum-steerer fork.


Yup. Hincapie was on an aluminum steerer.

And yes, he was riding a King headset Have not read anything about King headsets being the kiss of death to steerers though.


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## stevesbike (Jun 3, 2002)

for all those worried about carbon components, you should really be worried about aluminum ones. You should google "aluminum fatigue limit" for some interesting reading. The bottom line is aluminum will eventually fail due to cyclic stress. FWIW, the only components I see regularly fail are lightweight aluminum ones - all those 115 gram stems etc. Also, carbon does not 'go soft' it simply isn't a property of the material. It's brittle (that's why it snaps instead of bends like alum or steel).


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## longcat (Nov 8, 2008)

*I'm not pessimistic at all, not at all*



stevesbike said:


> for all those worried about carbon components, you should really be worried about aluminum ones. You should google "aluminum fatigue limit" for some interesting reading. The bottom line is aluminum will eventually fail due to cyclic stress. FWIW, the only components I see regularly fail are lightweight aluminum ones - all those 115 gram stems etc. Also, carbon does not 'go soft' it simply isn't a property of the material. It's brittle (that's why it snaps instead of bends like alum or steel).


And the only **** I see fail is the carbon ****! How convenient.

Lets just all agree carbon sucks cocks, I've been biking for over 20 years and I never even heard of steerers breaking, until "carbon" became the standard that is.

Shoot that **** to outer space, thats the only place no one will get hurt because of it!

Lets just face it, carbon sucks ass because its only a massively hyped fragile crappy material, but a somewhat "strong" material (600Mpa dont cut it in my book, but thats just me, 1/2-1/3 or so of commonly used steel!).

I feel its inappropriate for any kind of imaginable bike parts except 2kg road frames. Car-bone turds imo.

Carbon sucks ass, every other post on the intarwebz is about "will this frame explode and kill me because of this crack etc etc, that **** just sucks! **** carbon I say! Why even bother, should I rack out the penetrants to look for cracks in the top coat, wooden hammer for loose delaminated fibers running amok on the inside of the tubes, MRI-scans for the **** I may have missed?? 

Its a joke and the joke is on you.

"but they win toor the franz on those" no ****, but they have many many of those! And you dont!

The guys I work with are the top people on the planet, they were making carbon fighter jets 20 years before the US even noticed this material existed, and they sometimes ask me, just for fun, if my new frame was made out of "composite" (of course its always 4340 or 4130 steel), they know all too well how this material behaves, jets coming back with holes the size of peas in their wings, in several places, what a ****ing joke, and the people designing and building these really know their ****! 

Funny how these problems seems to stay under the radar for over 100 years but now just happening to surface, Gotta suck to be the one of the guinea pigs!

I can go out and buy a whole bike thats 50 years old for less than 50 bucks and run it on a downhill course (I´m not a downhill rider btw), and it will be working for 50 more years after that, and you all know it! Its made out of non Reynolds 853 suck ass weak steel, but even that "inferior" material is more long lived than the best CF out there, go figure.

Carbon is a joke for almost all parts on a bike, and if I owned the test equipment to show you I would (and since I do what I do I may have to design and build this equipment just to prove my point). Chinese carbon, gimme a fukn break, theyre just hacks capitalizing on the carbon "fashion", that it. Nothing more

I can go out today and buy a 50 year old steel bike, that has been used daily for 50 years, and I have complete trust in that, name one single carbon part that will last for 10 years with confidence? trek oclv?

Even the carbon/carbon (carbon fiber (melted) re-inforced graphite) they put on the space shuttles sucks ass so much it killed the crew on a shuttle. Imagine that! And those are made to a quality level several hundred-thousand times better than a bike frame or component!

**** carbon **** 

should say fuk carbon sh!t

I think


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## rook (Apr 5, 2009)

*Still wouldn't recomment a King threadless headset*



holy cromoly said:


> Yup. Hincapie was on an aluminum steerer.
> 
> And yes, he was riding a King headset Have not read anything about King headsets being the kiss of death to steerers though.



I should clarify myself. A King threadless headset will put a mark in ANY steerer, not just carbon. I have seen several steel steerers that have had the scoring mark put in them by the top part of the King headset.

I actually thought that Hincapie had a carbon steerer. My mistake. However, the King headset has a design issue that puts the scoring mark in a steerer. The King threaded headset is good, but I still would not recommend a King threadless headset. No way. Especially not withh a carbon steerer.


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## longcat (Nov 8, 2008)

here is info on the headsets and what they do 

*"KUOATE"*

http://www.pvdwiki.com/index.php?title=The_BEST_Headset

The Best

The finest, greatest performing headset that I have ever owned is also one of the best values, the Cane Creek S-3. Commonly available for less than $30.
[edit]
Why not a Chris King headset?

Back in the day of threaded 1" steerers, only two real performance options existed for bicycles, the Campagnolo Record HS-01OR Headset or the Chris King Two Nut headset. Both were fantastic options for both on and off road.

Then came threadless and oversized threadless steerers and other new developements. Chris King was one of the first to adopt the new systems, but Dia-Compe USA (now Cane Creek) made key developments in the threadless headset (AheadSet®) and holds the patent on the design using a split compression ring (U.S. Patent #5095770). This split compression ring is how the system is able to maintain concentricity among the mating parts.

The biggest initial problem with the Dia-Compe parts was overall percived quality. Others followed and improved their designs, but for many years, the Chris King NoThreadset headset was the only quality choice available, but things have changed.

The real Achilles Heel of the Chris King design is the way that the top plate is held concentric to the steerer tube to avoid tresspassing on the Dia-Compe patent. An o-ring is used to hold the top plate centered. The problem with this design is that when strong enough forces are introduced to the fork, the o-ring gives a little and the steerer is pushed off center of the headset.

Many people will see:

* Wear marks on their aluminium steerers
* A wear pattern on the taper of the base plate
* A wear pattern on the taper of the top plate
* Wear between the top plate and the first spacer or stem if the delrin shim is not in place (you were wondering what it was for?) 

*"KUOATE"*


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## Balderick (Jul 11, 2006)

Steve-a-Reno said:


> I don't mean to insult you or the mechanics) but are you sure your headset is installed properly? Are you running a CK or a different type that uses a compression ring to take up slack between the steerer and upper bearing like in the attachment?
> 
> .


That was the first thing the LBS owner checked, and my friends who own another LBS had their staff check that out as well. The headset is, I am told, installed properly. The headset is an FSA headset and the compression ring is fitted.

I have fitted the forks off my 2003 Giant TCR Composite 2. It has a Al steerer. The flexing problem has disappeared (not that I am surprised by that). 

Not coincidentally, a young guy who works at the LBS I purchased this bike from also rides a bike of the same brand. He looks like he weighs less than 60kg, and is not a person who many consider to the a powerful rider. He had a carbon steerer break in a race - no, he did not hit anything. The Importer has taken a very long time to provide him with any response and he is still waiting for a replacement fork. Interestingly his broken fork had similar delamination on the part of the steerer where the stem was fitted - just as the two forks that I have had problems with. The delamination was not where the headset is but above it, where the stem clamps on to the steerer.

His view - and he is a 19 year old with no formal training and little practical experience, so take what you will from it - is that the carbon steerers are made from substandard carbon - he used the word "[email protected]". I am not so sure about that, but do wonder whether the increased use of HM carbon (as these forks claim to be) might be undesirable. That is, and I am asking a question rather than making a statement, is HM carbon (or are some types of HM carbon) less suitable for use as a fork steerer than other types of carbon?

One positive - the failure of my two forks was something that I was able to detect before there was a catestorphic failure. However, my young friend's fork failure was catestrophic, in circumstances where he would unlikely to have put a signifcant amount of strain on his bike.


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## CleavesF (Dec 31, 2007)

stevesbike said:


> for all those worried about carbon components, you should really be worried about aluminum ones. You should google "aluminum fatigue limit" for some interesting reading. The bottom line is aluminum will eventually fail due to cyclic stress. FWIW, the only components I see regularly fail are lightweight aluminum ones - all those 115 gram stems etc. Also, carbon does not 'go soft' it simply isn't a property of the material. It's brittle (that's why it snaps instead of bends like alum or steel).


+1

Aluminum has no endurance limit, hence catastrophic failure and need for constant inspection (eg: airplanes). 

Steel on the other hand, has an endurance limit, and will show signs before fatigue failure unlike aluminum. 

Anyways, I love my Alu bikes lol. :blush2:


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## fasteddy07 (Jun 4, 2007)

*Jump*

Wow 

I have a carbon bike. And a few steel bikes, and an aluminum bike (couple)...
Been riding a while (some 35 years or so)

I like my carbon bike. I like it a lot.
I don't worry one bit about it blowing up either.

I don't worry much about any of my rides..

I think you ride what you want to - get on with it.

I have worked in machine shops and as a welder of some neat stuff - I know a fair bit about building things out of various materials -
If you step out of the bike context for a moment - you find failure is not all that un-common.
It is when it becomes a pattern, then you can jump up and down..

I think people sometimes like to jump up and down just because then can...


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## nightfend (Mar 15, 2009)

The problem with all of these type of threads is that this being the internet, all the bad news will surface and make the problem sound worse than it is.

In the last four years I've been riding carbon bikes, I've never had a carbon failure. This includes riding carbon steerer forks, carbon seatposts, carbon cranks and carbon stems.

For that matter, I ride everyday and do group rides twice on the weekend with large numbers of other people. In the last four years I have not seen anyone have a steerer failure on a fork. Nor has anyone I've been riding with told me they've ever had a problem like this.

For that matter, the only time I see carbon break is on impacts from crashes in races.

People need to put this all in perspective. We are talking about very small numbers of people having problems here. Most likely there were just as many failures of aluminum parts in the 80's and 90's, it's just that people didn't have internet forums to voice their problems.


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## spudbiker (Mar 25, 2006)

My carbon steerer fork imploded as I was rounding a corner, thankfully light traffic, out of the saddle. Wondered what that horrific sound was (carbon cracking) right as I was endoing into the road. Luckily caught the pavement with my shoulder and hip, not my face.
I defer to all of you on the technology, materials, expertise, etc. I weigh 183 lbs, trying not to be a masher, but will never use a carbon steerer fork again.


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## B15serv (Apr 27, 2008)

Also on the 3T stem. I recently bought the ARX stem from them as well as a Doric Team Carbon post and Ergonova LTD bars. The parts are top notch.


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## Le Wrench (May 12, 2009)

nightfend said:


> People need to put this all in perspective. We are talking about very small numbers of people having problems here.


True, it is a small percentage that suffer breakage.

The question people need to ask themselves is, do you want to be that person who ends up being the percentage.

For me, the answer is no. I know sh*t happens and I don't want it to be me. I have broken my shoulder before and had faceplant injuries from other sports, and know the pain and inconvenience involved. A carbon steerer's performance gain (?) is not worth the potential breakage and health issues that might ensue. But this is just my opinion.

Everyone needs to decide for themselves.


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## tom_h (May 6, 2008)

"Composite" forks, ie a metal steerer tube bonded to an otherwise carbon fork, can have its own problems associated with joining dissimilar materials. 

Eg, read:
http://www.cpsc.gov/cpscpub/prerel/prhtml09/09234.html
*Hazard: *The fork can separate from the steerer tube which can cause the rider to lose control, posing a fall hazard.
*Description: *This recall involves 2005 Novara Trionfo bicycles with Aprebic carbon fiber forks. The bicycles are blue and white with black forks, and have the name “Novara” printed on the bars.​Most road bikes over $1k have carbon forks nowadays, and I bet most of those are metal steerer tubes. All-carbon fork is still a "premium", more $$ item.


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## stevesbike (Jun 3, 2002)

here is a link to a column by Zinn with manufacturer recommendations regarding carbon fork lifespan. The consensus of the industry is that a carbon fork is longer lasting than a metal one. It is also worth noting that the REI fork recall (google it) was due to 2 incidents - that's a lot of consumer oversight. So stop worrying so much and go out and ride!

http://www.velonews.com/article/3270


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## Lookbiker (Sep 2, 2006)

I saw a rider get injured after his steel fork snapped during a race in the 80s. He claimed the fork was never crashed but it failed in any event. Any part can fail dramatically and it just sucks if that 1 in a million failure happens to your fork. I like my carbon fork and pay attention to proper torque settings and just ride. 

I'm more worried about that car passing me going 60mph six inches from my leg than sudden fork failure....


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## CleavesF (Dec 31, 2007)

stevesbike said:


> here is a link to a column by Zinn with manufacturer recommendations regarding carbon fork lifespan. The consensus of the industry is that a carbon fork is longer lasting than a metal one. It is also worth noting that the REI fork recall (google it) was due to 2 incidents - that's a lot of consumer oversight. So stop worrying so much and go out and ride!
> 
> http://www.velonews.com/article/3270



Another thing to note is that *multimaterial bonding * is usually not the best way to hold things together. 

Having an all CFRP epoxy matrix versus a CFRP-Aluminum epoxy matrix definitely makes a huge difference in the microstructure of the materials. 

There's a reason cast iron would ride just as well as carbon fiber, but it's just too damn heavy.


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## terbennett (Apr 1, 2006)

At 6'3", 210 lbs, I avoid them at all costs. Most bike shops I've been to steer me away from bikes that have carbon steerers. They tell me that I'll destroy the fork. In this situation, I would have to agree with them. carbon steerer forks are designed more for the sub 180 lb. group of riders. You dish out alot more watts and torque when sprinting and climbing than a lighter weight rider. You definitely need to stay away from carbon steerers. Get one with an aluminum steerer and you'll be fine. I did that on my Felt F55 that originally came with a full carbon fork.


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## CleavesF (Dec 31, 2007)

terbennett said:


> At 6'3", 210 lbs, I avoid them at all costs. Most bike shops I've been to steer me away from bikes that have carbon steerers. They tell me that I'll destroy the fork. In this situation, I would have to agree with them. carbon steerer forks are designed more for the sub 180 lb. group of riders. You dish out alot more watts and torque when sprinting and climbing than a lighter weight rider. You definitely need to stay away from carbon steerers. Get one with an aluminum steerer and you'll be fine. I did that on my Felt F55 that originally came with a full carbon fork.


Huh? Again, the Hincappie crash. 

Carbon fiber is and excellent material, but what people dont' know is that most carbon fiber forks with carbon steerers are not monocoque (one-piece) construction.

If you buy a carbon monocoque fork, say a Look HSC5/6 or Easton EC90, those forks, are so much stronger than the 2 or 3 piece carbon steerer forks out there. Even the Reynolds Ouzo Pros are not monocoque, and if you look on their website, they stopped making forks altogether!

The more bonding sites you have, more prone to failure. How many pictures of EC90 or HSC5/6 forks do you see around breaking at the steerer? Very few if any. 

If you compare that amount of failures of 100% monocoques to 2/3 piece carbon forks, you'll definitely see where the money goes. 

It's not a marketing gimmick in this case (maybe the comfort and faster claims are) but the ones about strength are not. 

Aluminum will fail, and should be given a fatigue life to consumers (eg: amount of cycles). Yes, bad batches of materials occur, but there's many things in engineering that gets screwed up along the way. 

There's bad material science, and there's bad engineering, and sometimes there's both.


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## Camilo (Jun 23, 2007)

stevesbike said:


> here is a link to a column by Zinn with manufacturer recommendations regarding carbon fork lifespan. The consensus of the industry is that a carbon fork is longer lasting than a metal one. It is also worth noting that the REI fork recall (google it) was due to 2 incidents - that's a lot of consumer oversight. So stop worrying so much and go out and ride!
> 
> http://www.velonews.com/article/3270


I loved that article and the various manufacturer's explanations. For example:

Easton, True Temper, Reynolds, etc.: 
..tech speak... test results... engineering terms... all very interesting.

Deda :

Carbon lasts longer than metal. Only love is stronger than carbon...

LOVE those Italians. Gotta go there again!
!


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## tom_h (May 6, 2008)

Camilo said:


> ...
> Deda :
> Carbon lasts longer than metal. Only love is stronger than carbon...


 Until the divorce ;-)


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## longcat (Nov 8, 2008)

tom_h said:


> "Composite" forks, ie a metal steerer tube bonded to an otherwise carbon fork, can have its own problems associated with joining dissimilar materials.


Yes, first and foremost the materials have different coefficient of thermal expansion, you can easily crack CF when cooling if the tool is made ouf of aluminum for example (if using prepreg and autoclave) , this will happen at a much lesser degree at room temp (the expanding and contraction), but having materials that expand dissimilar to each other is bad, especially if they were to be working as one component.

I also feel that if you have to have carbon make sure its mono-cock, I seen some pics at this site http://www.bustedcarbon.com/ of frames that were premade tubes bonded to well whatever the rest is called (I would call these muffs and tubes) and usually since these tubes are not machined and the inside of the muffs are not machined you get crappy mathing in tolerances here, and epoxy is not strong as a material but strong as a bonding agent, you know the thinner the better, and trying to fill empty space with it counting on it being strong is retarded. monocoque all the way.

And I also heard you need to etch the metals being bonded to get an approporiate surface for the epoxy to stick to, and preferably it goes:

metal - etched surface of metal - glass fiber - carbon fiber to make the bond really good (the glass fiber may or may not have to do with the thermal expansion dont know)

I have seen many pics of broken parts where the metal part looks like it was not etched or even sanded/lightly abraded before bonding, thats a big nono even to me. Never try to glue stuff to polished/fine surfaces, its like glueing glass to glass.

Now since manufacturers dont give a sh1t about this I´d stay away from from metal/CF hybrid parts, since they dont know wtf theyre doing. The carbon part is hard to F up and I assume/hope by now they have some sort of experience with this so this is the safest bet imo.

btw sorry for posting that thing I did above, I was drunk and it seemed like a good idea at the time.


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## rook (Apr 5, 2009)

*Seems to me that the some companies take safety more seriously than other companies*



stevesbike said:


> here is a link to a column by Zinn with manufacturer recommendations regarding carbon fork lifespan. The consensus of the industry is that a carbon fork is longer lasting than a metal one. It is also worth noting that the REI fork recall (google it) was due to 2 incidents - that's a lot of consumer oversight. So stop worrying so much and go out and ride!
> 
> http://www.velonews.com/article/3270



From the article, it seems as though the Italians are very much more into flair/marketing than into adequate product safety testing. Alot of the answers seem to be of the variety of an "I have no idea" variation. True Temper seems to be the only one who does any sort of rigorous product testing. After reading this article and the answers from each company rep, I would feel safer and more inclined to buy a True Temper or Reynolds carbon fork.


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## durianrider (Sep 26, 2009)

The main cause of carbon steerer failure is riding with more than 5mm of steerer showing above the stem cap. This means your steerer is now hollow as the steerer plug is not going deep enough to provide internal support against the upper and lower stem bolts.

Next most common cause is big guys riding steerers with more than 30mm of spacers under the stem.


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## Srode (Aug 19, 2012)

durianrider said:


> The main cause of carbon steerer failure is riding with more than 5mm of steerer showing above the stem cap. This means your steerer is now hollow as the steerer plug is not going deep enough to provide internal support against the upper and lower stem bolts.
> 
> Next most common cause is big guys riding steerers with more than 30mm of spacers under the stem.


Wow, 9 year old thread resurrected! What prompted this?


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