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Hi everyone,
I am considering switching from ITM aluminum handlebars to a Carbon handlebar and stem. I have read varying opinions on the benefits of CF vs. the cost, but I am wondering as a bigger rider (approx. 250#), whether the CF handlebars are advisable. Thanks in advance.
 

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i've got zipp SL bars, doubt i'd buy another pair of carbon. they cost a ton (got my used from a friend that got the wrong size) they only save a little weight, and if you crash you'll question their condition as they will hit the ground every time.
 

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filtersweep said:
May I ask why you are switching? Carbon is lighter and looks cooler, but that is about all. I believe a carbon stem is a complete waste, since there is so little carbon in it, and you still need a clamp, etc.
I have a Zipp carbon stem, which is full carbon, and the bar and I like it a lot more than my previous aluminum setup. There is a noticeable lessening in road vibration and and increase in stiffness -when I am climbing hard there is zero flex (well zero perceptible flex anyhoo)- which is very nice, and much needed on my daily commute :rolleyes:.
But that could mean I just had a not very good alu. bar/stem I suppose. They were ITM stem/ modolo bar - mid range.

Of course the carbon might spontaneously explode, so there is always that to worry about.
 

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weight limit??

I've never heard of a weight limit for carbon bars. You're not sitting on them and a properly fit rider will never have much weight on his hands, regardless of how much he weighs.

As a test I once took a pair of carbon bars, placed them on their side, on the floor and then exerted all 135 lbs of my weight on the opposite side, lifting myself off the floor. The carbon bars deflected noticeably less than some aluminum bars, given the same test.

Anyone who bought carbon bars expecting an improvement in comfort had the wrong idea. A few models may be lighter, but some are heavier than Al. One of the advantages is that more complicated shapes can be made with CF.
 

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tferris said:
I have a Zipp carbon stem, which is full carbon, and the bar and I like it a lot more than my previous aluminum setup. There is a noticeable lessening in road vibration and and increase in stiffness -when I am climbing hard there is zero flex (well zero perceptible flex anyhoo)- which is very nice, and much needed on my daily commute :rolleyes:.
But that could mean I just had a not very good alu. bar/stem I suppose. They were ITM stem/ modolo bar - mid range.

Of course the carbon might spontaneously explode, so there is always that to worry about.
Interesting notion. If there is less less energy reaching you hands, it's gotta be going somewhere... Which if there is 'zero flex' is clearly not happening. If they're less flexible, they're less comfortable. I'll allow you either belief, but both is a violation of a few laws of physics. Perhaps there's a perceptual filter in effect.

OP: Get 'em if you want 'em. Weight savings are negligble to negative, cost is pretty crazy, and there is absolutely not any dynamic difference that will mean squat to how fast or comfortably you ride. Some of the shapes they do in carbon are better than what they manage in aluminum, so that's a positive.
 

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perhaps you should add tensile and compressive modulus properties to your list of physical properties. The anisotropic properties of CF are what allows it to have very different values for these two key features. Also have a look at the passive damping properties of CF vs. aluminum. There's a reason why the industry likes CF beyond the pretty carbon weave...
 

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danl1 said:
Interesting notion. If there is less less energy reaching you hands, it's gotta be going somewhere... Which if there is 'zero flex' is clearly not happening. If they're less flexible, they're less comfortable. I'll allow you either belief, but both is a violation of a few laws of physics. Perhaps there's a perceptual filter in effect.
OK to clarify, I think there are two different things going on here, one is the harmonic resonance is lessened, they seem "deader" than my aluminum bars with road vibration, until you get the level of bad chip seal then it seems no different. But the flex issue I am referring to is when you are out of the saddle and really pulling hard on the bars- thats something completely different than road buzz, more akin to hitting a big bump, which is also more jarring and noticeable now. So I am wondering, can the bar be more forgiving at some frequencies yet more rigid in other areas, either because of the way the bar is built or inherent properties? I could feel the flex dramatically on the old bar and stem but it seems incredibly rigid with the new bar and stem. Carbon does not resonate like aluminum does right? I mean how could it, carbon and aluminum are not exactly equal in composition. If I hit a carbon bar with a hammer it does not ring like a bell. As materials go they are quite different right?

I know this is dangerous territory because people get all fired up over this... so sorry OP for the hijack.... but I would really like to know. Is there a difference or... placebo on the road buzz? If I had to choose one, the rigidness while climbing or out of the saddle is hugely apparent, while road buzz reduction is subtle and not noticeable at a certain points.
 

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stevesbike said:
perhaps you should add tensile and compressive modulus properties to your list of physical properties. The anisotropic properties of CF are what allows it to have very different values for these two key features. Also have a look at the passive damping properties of CF vs. aluminum. There's a reason why the industry likes CF beyond the pretty carbon weave...
oh funny I just saw this after my last post
 

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I've never heard of a weight limit for carbon bars. You're not sitting on them and a properly fit rider will never have much weight on his hands, regardless of how much he weighs.
"Specialized compsoite handlebars are made to be lightweight, and are not suitable for all riders and possible uses. If the rider is approaching 250 pounds in weight (i.e., 240 pounds, etc.), Specialized recommends against use of this handlebar. Failure to follow this warning may result in a catastrophic failure of the handlebar, causing serious injury or death."

http://cdn.specialized.com/OA_MEDIA/pdf/manuals/S-Works_Barmac_Wedge_r1_final_OL.pdf
 

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There's no way to convince anyone of this over the internet, but...

The thing that makes a composite structure able to damp vibrations is a relative excess of epoxy. A 'dry,' high-pressure composite can ring like a bell. OK. But, adding composite decreases strength, requiring additional layers (and so still more weight) to bring the strength and stiffness back up. So yeah, it's nominally possible to have bars that damp vibrations to some degree and are nicely stiff - but they end up heavy as hell.

More importantly, 'harmonic damping' as applied to bike handlebars is a marketing dodge. Bars simply don't 'ring' once they have tape and levers installed, and courtesy of hands at one end and tires at the other, aren't struck in a manner that would allow them to anyway. The only thing that's relevant to human comfort here is road shock, that's all about having some measure of spring to absorb those shocks. Obviously, spring effect and stiffness are at odds.

One of the more interesting things here is that the much-derided 'wrap' bars (carbon over an otherwise too-thin aluminum mandrel) can produce an excellent balance of weight, stiffness, and damping. Unfortunately, after a few makers did it as an aesthetic rather than engineering option, they got a bad reputation.

Note: the nature of loads on an element matters. Frames and forks for example are a different discussion. Only to say, talking only about the material's inherent properties is a meaningless discussion.
 

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I weigh about 275 or so and I ride a kestrel carbon bar. They have a no fault warranty so if you break it you send it back. I have a new Zipp bar that I have not mounted yet but it is suppose to be stiff. I am also waiting on a Bontrager xxxlite which is fairly stiff yet lightweight. One thing to keep in mind being a bigger guy is the bar width. I am fairly limited because most companies measure carbon bars outside to outside not center to center. Keep in mind the sizing issue.
 
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