Civia Carbon Fork Recall

Civia has issued a product safety recall on all of their carbon forks. From the Civia Blog:

Product Safety Recall Notice
Mon, Mar 15 2010 3:14 pm Written by: Scott Thayer
A few weeks ago we became aware that our carbon fork does not meet our expectation for product safety. We have seen a couple forks begin to crack around the steerer tube and one had the steerer tube separate entirely from the fork legs. Thankfully, the rider was not seriously injured when the separation occurred.

We’ve conducted 3rd party testing and have concluded that the problem we’re seeing is the fork was designed to be stiff so that under braking, the legs would not wander around creating a noodly fork feel. An unanticipated by-product of this leg stiffness is that the fork legs aren’t moving at all during regular braking and in turn, all of the braking force is passed up to the crown. These forces are over time will lead to potential failure.

We are in the process of contacting all of the bike shops that have purchased forks, or Hylands with the forks installed. The dealers will be working to contact all of the consumers that have purchased Hyland bikes or Hyland carbon forks. 100% of the Civia carbon forks are affected by this recall.

If you own a Hyland that has a carbon fork, or have purchased the Civia Carbon fork, please contact your dealer for information about how to go about obtaining a replacement Civia steel fork. We are also extending a credit to the consumer through the bike shop as compensation for the change in value from carbon to steel. For more details of the recall, please contact the dealer you purchased your Hyland or carbon fork from.

Beginning now, all Hyland complete bikes are coming with Civia steel forks. Pricing has been adjusted accordingly so that now Alfine builds are retailing for $1,575 and Rohloff builds for $3,250.

Thanks for your understanding as we go through this.

Scott
Civia General Manager
scott@civiacycles.com
952-229-5040

Civia

46 Responses to “Civia Carbon Fork Recall”

  • Dolan Halbrook says:

    Wish Grant Peterson’s worries weren’t so timely. Makes me jittery about the one carbon fork I own, though it doesn’t have a carbon steerer (not that it matters if the two shear off from one another).

  • Alan says:

    Ironically, I’m riding my Hyland today. I’m not terribly concerned about it for the short term, but I will have the fork replaced.

    Alan

  • Rick says:

    @Dolan:

    Funny, I was just thinking about Grant! Bet Alan will ride the Sam Hilborne tomorrow! :-)

    @Alan:

    Please no potholes on the way home, okay? :-)

  • Dweendaddy says:

    It does make me wonder…. even if you are not a Petersen acolyte, why would you care to have a carbon fork in a bike made for commuting? It limits the flexibility in shapes/clearances, and is more expensive to boot!

  • Dolan Halbrook says:

    @Dweendaddy

    This seems to come up over and over again. There are advantages to carbon forks, namely weight and ride quality. That said, I too question its use for a commuting bike.

  • Sished says:

    Sorry to hear this news especially as Civvia are such great cycling for transportation advocates. However, unless you’re participating in the Tour de France or appearing at the Olympic velodome, what exactly is the point of carbon anything on a bike?

  • Don says:

    A carbon fork is one of those specs that will always inspire skepticism from “rider on the street” looking for value. I think you can sell the disk brakes, the internal hub gearing, the belt, but carbon? It plays into the stereotype of effete elitism. Aluminum with a CroMo fork is plenty.

  • AdamM says:

    Glad I wasn’t the only one to think of Grant when I read this. I just don’t understand using carbon on a commute bike. Commute bikes get locked to things, they get knocked around, they get scratched and they get dropped or knocked over (even if not by the owner). The worst that would happen to a steel fork is the paint might get chipped; with a carbon fork you can never quite be sure if any internal damage has been done.

    I also question the perception that a carbon fork improves the ride quality of a bike. Maybe over a cheap rubbish steel fork, but not compared to a sell designed and made modern fork. Besides, once you put disc brakes on a bike all bets are off due to the design requirements to cope with the disc brake forces.

    I had to laugh at this bit: “We are also extending a credit to the consumer through the bike shop as compensation for the change in value from carbon to steel.” To my mind, putting a steel fork on this bike improves its fitness for purpose and thus its actual value (as distinct from its price).

    Having said all of that, it’s great to see Civia standing up, acknowledging there is a problem and going out of their way to fix it. Well done.

  • David says:

    The point, of course, is light weight and damped resonance. The fork is one of the heaviest components of the frame and so it’s a particularly good target for carbon construction. It’s also the primary route of road vibration to the hands and the dampling characteristics of carbon can help there as well. I’m sorry that Civia is having to recall their carbon fork, but it’s due to the specific design flaw of this fork and is not an indictment of carbon fiber as a material. With proper design, this wouldn’t have happened and it doesn’t happen on numerous other carbon forks on the market that are used just as heavily.

    You don’t have to be a weight weenie to appreciate a lighter frame or components. Case in point, my old warhorse 1993 commuter bike weighs in at a relatively svelte 28 lbs despite having a steel frame and fork. If I were to outfit that same frame with disc brakes, an IGH, kickstand, Schwalbe Marathons, and all the other things that a modern commuter can appreciate, it’d top 33 lbs. If I were to buy a bike like the Breezer Finesse, Civia Bryant, or build their equivalent out of good steel tubing with a carbon fork and seat post, belt drive, alloy rail seat, and other components that save weight without adding huge cost, I could have all the modern conveniences and still be close to 28 lbs. I don’t know about you, but I can definitely tell when my panniers are holding an extra five pounds and I’d rather not lug it around if I don’t have to.

  • jon shinefeld says:

    A couple of posters mention the enhanced ride quality of a carbon fork. Has this benefit ever been quantified? I’m asking because I’ve come to believe that ride quality (vibration) depends on the tires and a flexy curved steel fork. You know, fat tires with compliant sidewalls at 60-80 psi ride softer than skinny tires at 100 – 120 psi, and a steel fork that flexes with road shock. Isn’t carbon really stiff? How does it give a better ride?
    Thanks – appreciate informed feedback.

  • Lovely Bicycle! says:

    Oh no, scary carbon fork!

  • jnyyz says:

    I’d agree that carbon is not suited to a commuter bike, where things can get bashed around. Chain wear on carbon rear triangles is a known issue on many bikes. In the case of this fork, I’m sure the fact that it is a disc fork makes the design issue more difficult. Finally, carbon has a nasty habit of failing without warning. It will be interesting to see how the Boeing Dreamliner does ten or fifteen years down the line, once large numbers of them are finally in the air.

  • Bill says:

    One important aspect of designing for light weight is in avoiding concentrations of stress at a point where failures can be induced. Apparently Civia has learned that lesson the hard way.

    The problem can be as easily blamed on the disc brake as on the material. If the braking force was all at the crown instead of down at the bottom of the fork blade, this particular failure mode would probably not have appeared.

    Full disclosure – I own a bike with an all-carbon frame and fork, but it has caliper brakes, and I sure don’t commute on it! That bike is just for Sunday go-fast rides with the local club. The rest of the fleet is all steel.

    Bill

  • Tim says:

    Dolan Halbrook says:

    “There are advantages to carbon forks, namely weight and ride quality.”

    I would say weight is the only objective advantage. “Ride Quality” is such a subjective idea that it really can’t be quantified. I, for one, like G. P. find anything but high quality steel to be atroscious. This doesn’t mean that I have proof that this is factually so, it is just my humble opinion. (But really, it’s true).

  • Joe says:

    I also applaud the decision from the manufacturer to call in the forks, it says a lot about their commitment towards their customers.

    Having said that, I’m with many of the posters saying that carbon is ok for racers and those who think weight is that important (and money in the wallet not so much :-). For commuters, travellers, etc. that should be looking at resilient and long lasting components, it’s just not the right choice. My mtb is from 1992, and after its very heavy use, I know it wouldn’t be still here if any of its components were made of carbon (it’s all steel, including its rigid fork).

    I consider a suicide to have the main passive safety components in a bike (fork, handlebar, stem,…) made in carbon, at least for normal users. Racers and professionals are ok, because they get new stuff every second week, so they don’t need to worry if the components last or not…

  • Matt says:

    I thought the carbon fork was a bad idea from the time it was introduced on these bikes so I’m not surprised to see a recall after a relatively short service time. Civia had better hope they don’t get tagged with the Death Fork moniker like Lambert/Viscount and their aerospace engineered aluminum forks in the 1970s. It at least sounds like they’re not in denial about it.

  • bongobike says:

    No one needs carbon forks, or carbon anything for that matter. And as big and heavy as I am, I would never ride carbon–makes me nervous.

  • Saddle Up says:

    If “Ride Quality” is such a subjective idea that it’s really can’t be quantified I would have to assume that my mass market made in Taiwain Masi Speciale Commuter is the equal to bikes like Alan’s steel IF. Why then would someone pay a premium if ride quality cannot be quantified? If there is no quantifiable ride quality difference between a carbon and a steel fork then steel is steel regardless of the grade or manufacturer. Seems no one is able to determine ride quality differences from the seat of their pants.

  • David says:

    There’s a big difference between “I would never ride carbon” and “No one needs carbon forks or carbon anything”.

  • bongobike says:

    David, there is. And both statements are true.

  • Rick says:

    David, when you say, “You don’t have to be a weight weenie to appreciate a lighter frame or components”, I do appreciate where you’re coming from–I raced pretty often in the 80’s–but as I’ve gotten older (and much, much slower), I now understand how weight is much less of an issue than is strength and reliability (well, that’s what I tell my wife…lol!)

    I’m 6’4″, and now weigh about 225, so for me the idea of using a potentially brittle material on my commuter bike to save the 5lb. you mentioned seems a bit silly; for me, I’d rather take home one less carton of milk. But in the end, it’s like the times I’ve answered the phone while working in the ER when sometimes calls, explains a problem, and asks, “is this an emergency?”; since I can’t adequately step into their shoes at that moment, I always reply, “if it’s an emergency to you, then it’s it’s a emergency to me–and we’ll be happy to help you once you get here”: if you think it’s best to have carbon fiber on your bike, then it’s best for you–and I would never feel I could tell what’s the right way for you to enjoy a bicycle.

    Cheers!

  • Steve says:

    Hopefully they have sword fights before dumping the forks.

  • dynaryder says:

    I’m pissed. I just bought one of these. The all-carbon fork was one of the premium details I liked about it. I’m not too happy about the fact that they just couldn’t swap a different carbon fork(Evo perhaps) instead of going steel. This is supposed to be a performance commuter.

    I love reading comments from the luddites. ZOMG! Carbon! I’ve never had issues with carbon anything on my streetbikes. My friend even had a carbon fork on his polo bike…until he crashed and dented the toptube. And I’m curious how you all feel about full carbon MTB’s?

  • doug in seattle. says:

    Regarding “ride quality”: the only time I can definite differences in the ride quality is the size and pressure of the tires. Seriously. My touring bike, made from cheap Reynolds 520 steel, rode like crap with 28/32 tires. After riding my 2″ tired town bike, it was like riding a bike with wooden tires. So I put a 40/37 combo on it and suddenly it rides like a dream. Much, much better. My average speed also went up because I could go a lot faster on rough surfaces and felt less sore after long days in the saddle.

    I think road buzz is what makes a bike uncomfortable over a long period of time, and the BEST way to fight that is to get fatter, softer tires.

    @dynaryder:
    I would ride a bike with a dented steel top tube. Even a massively dented toptube with rust, for a little while, anyway. I would not, however, ride on a bike with a scratched carbon fork. I think the “luddites” are against carbon components because the benefits do not compare well with the increased cost. I’ve never read a compelling reason to invest in anything carbon, since I can get 98% of the function/quality for a fraction of the cost. Also, despite your personal experience, there are plenty of documented issues with using carbon for critical components on daily riders.

  • Rick says:

    @dynaryder:

    Hmmm…so if I understand your post, there’s basically there’s two camps: riders who use carbon fiber, and the luddites who don’t? That’s a bit extreme, don’t you think?

    When you say, “I’ve never had issues with carbon anything on my streetbikes”, I believe that’s the point Grant (and many others) are tying to make: it’s great that you haven’t had an “issue”, and I sincerely hope that you never do, but the problem is one of not ever knowing when the “issue” comes up–because the point of failure regarding carbon fiber is so sudden. Everything will be just perfect.. until, suddenly, it’s won”t be. I can’t live with that, and I’m happy that you can, but I don’t believe that a rider enjoying an extra layer of safety while sacrificing an few ounces makes one a luddite. :-)

  • David says:

    Rick, thanks for the considered response. Carbon fiber has its strengths and weaknesses as a material, but so does steel, titanium, aluminum, bamboo, etc. Each can have a wide range of legitimate functions on a bike and, properly engineered, each can do the job without premature or catastrophic failure.

    No matter what folks claim, everyone rides for different reasons and one of mine is speed and a feeling of responsiveness from the bike. For me, weight is a demerit and I’ll study the cost/benefit of reducing weight everywhere on the bike. Typically, I’ll approach a bike design with a particular weight budget and will “spend” it where it’ll give me enough benefit (e.g. disc brakes, IGH, kickstand) and I’ll save it elsewhere (e.g. belt drive, carbon fork, carbon seat post) as long as it doesn’t cost too much to do so.

  • Grant says:

    It’s sad news for everybody, and for the record and sincerely, another carbon recall doesn’t make me feel validated, just sad for everybody involved. A recall is a bigger mess than you might believe. Dealers squawk and don’t always go along with the compensation plan (although in QBP’s case, it probably helps to be so important to them). It will cost more in shipping than the forks cost, I’m sure. More in labor than the forks cost, I’m sure. The new steel forks probably cost somebody more than the original carbons (depends on the details).
    In the old days in the ’80s, a maker was required to take out adnouncements in consumer magazines, alerting its customers to the recall; and the ads had to be equal in size to the ads used to promote the bike. A full-page ad in Bicycling costs around $35K, I think—I’m out of the loop, but was in it for years at Bstone, and I’d be surprised if it were any less than that. I doubt there were any full-pagers for the Civia there, but the point I’ll stop making here is that the monetary cost of a recall can be fifty or a hundred times the cost of the actual replacement piece.

    QBP is a fantastic company, and everybody I’ve met and know there is smart, honest, well-intentioned, and extremely pleasant. Too bad for everybody.

    Grant

  • Jay says:

    I don’t want carbon anything.

    My bike is a heavy steel XL Trek rigid 700c hybrid with swept back bars, fenders, bell, Ergon grips, lights, heavy duty rear rack, and basket on the back.

    I lock up to posts and racks in the city, and knock it against all sorts of things in my attempts to wrangle it up and down stairs to get it into my apartment. I am clearly not the intended audience for carbon. If I smack the side of my fork into another bike accidentally, it’s nice knowing I haven’t damaged it (other than maybe scratching the paint).

    For race bikes, sure, but for practical city bikes that aren’t always treated so gingerly?

    I wouldn’t want a full carbon mountain bike either. Or a car made out of it. Or on any product/vehicle that is often subjected to collisions. (Note I said collisions – that’s why it’s probably ok on planes).

  • bongobike says:

    Rick,

    you and I are the same size and weight, and I agree with you 100%. Whether you are a big heavy buy or a young, fit, lightweight person, I don’t think you gain anything from a carbon fork. You’re not going to get to your destination any quicker or less tired because of it. It’s just a fashionable toy. Your frame, tires, drive train and riding position may affect your speed and comfort, but a fork? I don’t think so.

  • Fergie348 says:

    Sorry to hear about the Hyland fork recall – it seemed like a nice spec for this bike but unfortunately it appears they didn’t do enough testing. To those who question the ride advantages of carbon, I can speak from experience having ridden (recently) aluminum bikes with carbon, steel and aluminum forks. If you commute over pavement that is rough or chopped up the aluminum fork will not make you happy. Steel and carbon forks feel roughly equivalent with carbon being generally lighter and a bit more flexy. That’s right, the steel fork is likely to be the stiffest of the three. Of course, there’s a tremendous amount of variability in how all forks are made and a high quality steel or carbon fork would be equally nice in terms of ride quality, with the carbon fork being lighter. Carbon is actually pretty tough, so durability wouldn’t be a concern for me. Most carbon forks are clear coated, so you see the damage more clearly than you do with painted steel forks. Steel, especially butted tubing, will dent whereas carbon will not. I’m 6’1, 200 lbs and I would have no concerns about having a carbon fork on my commuter, as long as it was manufactured with that intended purpose.

  • Roland Smith says:

    The fact of the matter is that failure behavior of composite materials is poorly understood.

    Even the experts cannot agree on a failure model that can correctly predict failure for in-plane loads, let alone out-of-plane loads. In 2004 there was a kind of competition called the “world-wide failure exercise” where the best and brightest of the academics working on failure models for composite materials were invited to predict the failure of certain laminates. In the second part of the study, actual laminates were tested and compared to the predictions.

    No single model got everything or even a majority of cases right.

    An additional disatvantage of carbon in that the breaking strain of the fibers is usually less than that of the matrix in which it is embedded. So it tends to fail catastrophically. In glass and aramid reinforced composites the matrix usually shows cracking before the fibers fail.

    I’ve been designing and building composite parts professionally for about 15 years, and I very much prefer to make a 1:1 prototype and test that than doing all kinds of calculations.

  • PJ says:

    Hello,
    I don’t want to enter myself into the debate over the merits of carbon on bikes here but I do want to say a couple things.
    First a big thank you to everyone, our customers, our dealers, our vendors for their help in getting this matter resolved. Grant put it well when he said it is sad news for everyone. We are very sorry that people are inconvenienced by this and want nothing more than to get folks back on their bikes and riding.
    Second if you have questions and or you are impacted by the recall and are not happy with how things have been handled please contact us. We are dedicated to serving our customers with excellence and I can think of no better time to prove that than now.
    Again thank you everyone and we are working very hard to handle this as quickly as possible and to make it as seamless as possible for those involved.
    PJ Ramstack
    Civia Cycles
    952.229.5040
    pj@civiacycles.com

  • David says:

    PJ,

    I’m sure this is the last thing you wanted to be dealing with in trying to get a new brand and business established. FWIW, how you’re handling the recall speaks very well of Civia. When I’m in the market for a new bike next year, I will be looking even more seriously than before at the Bryant. Of course, it will help tremendously if the Bryant has the Shimano 11 speed hub at that point too ;o).

    This too shall pass.

    Best,
    David

  • dynaryder says:

    @doug: massive dent right behind the headtube.

    @Rick: curious how my jab at the luddites put people in two camps?

    @PJ: not a happy camper here. I’m beginning to have flashbacks of my Buell experience. Once bitten,twice shy. Also,I’ve yet to hear anything about this from the shop that sold me the bike. How are you ensuring all your customers get the word? I just happened to be checking this blog(not a daily read for me) and saw the announcement. Curious where the disconnect is.

  • PJ says:

    dynaryder

    Please get in touch with Civia directly so that we can help you resolve this.
    We have only started the recall effort as of the end of last week so there is a chance the shop has just heard from us or we didn’t get in touch the first time and are calling back this week.
    Either way let us know who you got the bike from and we will get the process under way and work with you to come up with the best solution possible.
    Thank you,

    PJ Ramstack
    Civia Cycles
    pj@civiacycles.com
    952.229.5040

  • Giffen says:

    Roland Smith,

    You get my best post award for today!

    dynaryder,

    When you say “I love reading comments from the Luddites.” you must remember that the Luddites were protesting against new means of production, rather than improvements in a finished product. But no matter, because guess what? I’M A LUDDITE. That’s right. I’m a Luddite when it comes to bicycles. I would much prefer a roadster from the 30s to a new bicycle from a bike shop. The only bicycle innovation of the last half-century that interests me is kevlar-lined, puncture proof tires.

    David,

    This may shock you, but I don’t actually care about weight!! Really! My favorite bike, which I ride everyday is a pre-WW2 roadster with rod brakes. (Of course, if it had been built with a carbon fork, it would be unrideable today.) If I bothered to weigh it, it would probably be around 50lbs. But I don’t care! If you weigh 180lbs, then going from a 33lb bike to an 28lb bike is a 2.3% savings in weight. That is functionally negligible.

  • Giffen says:

    Roland,

    Out of curiosity: if a similar “failure exercise” was carried out with steel parts, with what accuracy would the failure modes be predicted?

  • David says:

    @Giffen,
    That doesn’t shock me at all, more power to you! I happen to like turn of the century bolt action rifles and think that a lot of the “improvements” in rifle design since then are nothing of the sort. With the exception of those that lower the rifle’s weight, of course. ;o)

    The point, of course, is different strokes for different folks. Someone may be a luddite with bikes but like the bleeding edge with other things or vice versa. It’s all good until people start dictating what others should and shouldn’t have based on their own personal biases.

    To drag Grant into this, I’m thrilled that he’s got a passion and has made it possible to share it with others of like mind. That his vision of the ideal bike doesn’t match mine is immaterial, there are other suppliers willing to provide my ideal bike but I’m glad he’s out there promoting what we can all agree on: the more people on bikes of any kind, the better.

  • Roland Smith says:

    @Giffen

    The failure of isotropic materials like steel is pretty well understood. And every kind of steel that has been standardized has its design allowables w.r.t. stresses etc.

    In a nutshell; that is impossible with composites.

    (For those not familiar with the term: isotropic means that this material has the same properties regardless of the direction you push or pull at it. Anisotropic means not isotropic.)

    Long version:

    Composite materials are anisotropic. They are built up in thin layers. In every layer the fibers lie in one direction (at least in the calculation; woven fabrics are seen as two layers with perpendicular fiber directions), and layers are stacked on top of each other, typically with the fibers in different layers pointing in different directions. The thing with laminated composites is that the stress and strain in the laminate and in the layers depends on the direction of the applied force. The fibers are much stronger and stiffer than the matrix that binds them; so a laminate or layer with a load applied in the direction of the fibers can carry a much higher load then when the load is applied perpendicular to the fibers.

    So as opposed to e.g. metals it is impossible to say in general that a certain laminate has a breaking strength of so many psi. You have to specify how the different layers are positioned, and in which directions the forces are applied. If you were to change the directions of the layers, the strength of the laminate will change even when you are using the same kind and amount of fibers and resin!

    Furthermore, there are several ways in which a composite can fail; e.g. the fibers can break, the matrix can crack or the layers can come apart. Another thing is that a layer of fibers embedded in resin is much stronger in tension than in compresion; you cannot push on a rope, after all.

    All these factors make predicting failure strengths of composites hard.

  • Roland Smith says:

    @jnyyz

    The aircraft industry knows a lot about composites. And more importantly, they do a lot of testing! Most methods for calculating and manufacturing composites originated in the aircraft industry. But indeed, even Boeing had some extra delay recently with the dreamliner when some stringers in the wing de-bonded from the wing panels.

    @PJ

    Compliments on the way you’re handling the situation! It’s the right thing to do. If I might be so bold as to make a recommendation about using composites; if you plan using a composite part, think long and hard about the expected loads and test at least five specimens (preferably from different batches) not just to spec but to destruction. That’s the only way to get a reasonable indication of the real strength as opposed to the design strength. In my opinion, a fork is not an easy part to make in composites. The geometry where the fork legs meet the steerer tube is not favorable because you’ll get considerable stress concentrations at that point. Just the thing you want to avoid with composites. Getting enough fiber in the proper directions in such a relatively small place to catch the bending moment caused by braking is difficult.

    @Jay, doug in seattle

    If well-designed, carbon fiber can take a lot. Surface scratches are not a problem. A collision large enough to make a dent in a carbon top-tube would have to literally destroy the material.

    I’ve seen a 6 mm thick carbon plate about 13 cm wide loaded with 250 kg about 30 cm from the point where the part was clamped. More than 90% of the fibers were aligned with the length of this part. The part deflected about 20-30 degrees without breaking! Only when we were in the process of adding an additional 125 kg weight did it break.

    You are correct that when carbon fiber parts break, they tend to do so suddenly. The material doesn’t yield and flow like steel does.

  • DrMekon says:

    Things fail. When they fail, I want a warning that doesn’t involve me loosing control of the bike. Ideally, I’d like enough warning to complete a ride. I don’t want something that shatters.

    I love the look of Civias, but the way bike parking is most places, that fork will get scratched. I am currently looking at audax bikes. The number I’ve had to take of the list becuase of carbon forks is ridiculous.

  • Andrew says:

    This just further reiterates to me that it’s not about the material, it’s about the design.

    I’ve said it before, and I’ll say it again – you could easily make a carbon fiber component with a mix of high, intermediate and low-modulus (or aramid) fibers that would be stiff, strong, impact resistant – nigh on indestructible – that would end up weighing the same as pop-can thin high end steel, which is absolutely not known for its durability. But then the weight savings that people who buy carbon buy into would be gone, and even if it was a stellar product, it probably wouldn’t sell. All parts need to be marketed somehow.

    Good on Civia for doing the recall. I guess a bit more testing is in order next time, but don’t let this experience scare you away from all the cool things you can do with composites…

  • Rick says:

    Wow, Roland! Thanks for reminding me why I’m not an engineer–not even after staying at a Holiday Inn Express! Lol!

    After looking over this conversation this morning, I was thinking about my childhood in Germany in the 60’s, and the several times my father and went to go see the Formula One races; my hero then was a young Scot named Jimmy Clark, and he raced for the lotus team, then headed by an amazing engineer named Colin Chapman. Jimmy died in 1968, the victim–they later found out–of a faulty tire; but until then, Chapman, and his principle of “lighter is faster” was challenged; you see, Chapman had a reputation for having brittle, fragile cars that would (at least it seemed to me) either break or win, and a couple of his drivers died having made that deal that the glory was worth the risk.

    So, in a circular fashion, I’d like to add that as long as the people are fine with the risk of having something so potentially dangerous (when Scott wrote, “Thankfully, the rider was not seriously injured when the separation occurred”, I wonder what type of conversation this would be if he’d been killed or permanently injured), then so be it–there just isn’t a right way or a wrong way to enjoy a bike. As long as people are given the complete–and I mean complete, even though we all know how sadly lacking the base of knowledge is for most bike shop employees these days–information when they buy a bike with carbon fiber parts, then more power to them. I don’t wear a helmet, and for me, the freedom of not having one on my head is worth is worth the risk, and I’m certainly not going to judge someone for having a similar approach while debating a different subject.

    Like the great philosopher, Forest Gump, once said, “that’s all I have to say about that”. Time to get out and ride! :-)

  • Dolan Halbrook says:

    One thing I find interesting is the lack of availability of Ti forks. Seems to me, apart from cost, Ti is the perfect fork material, for the same reasons it’s such a great frame material. Light, strong, great plasticity, reasonably predictable failure, etc.

    Likely it’s because there is far less profit margin in Titanium than composites, since the source material is quite expensive to begin with. I’ve only seen a few forks made out of Ti here and there, but nothing like the plethora of carbon composite options on the market.

  • Roland Smith says:

    @Andrew

    You’re quite right. But I wonder if the companies that make carbon forks have the engineering resources and knowledge to do proper design validation? Some are made by sporting goods manufacturers, and some by bicycles builders who started out in metal.
    A lot of composite sporting goods manufacturers are relatively small. And let’s face it, if hockey sticks, fishing rods or tennis rackets break it’s not that big of a deal.

    In the aircraft and also the medical device industry (where I work) design verification and validation is taken rather seriously because if we screw up, lives potentially are at stake.

    Personally I would not recommend mixing HT (high strength) and UHM (ultra high modulus) carbon fibers in one design; you’ll probably end up with the disadvatages of both! Nor would I recommend UHM carbon for things like bicycle parts because of its extreme brittleness and low strain limit.

    I’ve used Dialead K63712 UHM fibers which have an incredibly high Young’s modulus of 92 MSI, but a strain limit of only 0.4%. If you fold these fibers they’ll break! They’re great for designs where stiffness requirements dominate, though. They’re also about five times as expensive by weight as standard HT fibers, but only 2.5 times as stiff. And HT fibers are actually stronger.

  • EcoVelo » Blog Archive » For Sale: 54cm Civia Hyland says:

    […] installed, but I have a replacement steel fork on the way. Both forks are included in the sale (click here for info about the fork recall). You’ll see different saddles in the various photos of the […]

 
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