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Anti-Hero
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Discussion Starter · #1 ·
Here's another "don't use CF handlebars for CX" story for everyone (courtesy of Mr. 138): http://blog.roadcx.net/archives/851

He knew better, but decided to use them anyway since they came on a bike that he bought last year for components. I unwrapped & snapped the photos while he went to purchase some good aluminum replacements :D
 

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veldrijder
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444 Posts
Generally the only reason not to use carbon for cross is the greater frequency of crashing. Most all of the CF bars are as strong or stronger than their aluminum counterparts, and many manufacturers endorse them for use in cross but you can't really crash on them and expect to keep going without replacement as with alu bars.

So the moral of the story is not to ride CF unless you get cheap/free replacements from a sponsor, or you don't crash at all.
 

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Do not touch the trim.
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jmoote said:
Generally the only reason not to use carbon for cross is the greater frequency of crashing. Most all of the CF bars are as strong or stronger than their aluminum counterparts, and many manufacturers endorse them for use in cross but you can't really crash on them and expect to keep going without replacement as with alu bars.

So the moral of the story is not to ride CF unless you get cheap/free replacements from a sponsor, or you don't crash at all.
I don't know, there has to be a reason almost no road pros run carbon bars/stems.
 

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veldrijder
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Stiffness is the main reason. Not to be confused with strength - so a stiff bar might help your sprint on the road, but in cross likely makes no difference. The lighter weight of carbon bars makes no difference to the road pros since their bikes are all under the UCI limit anyway. On your average cross bike, it is a nice way to save 70g.
 

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Number 2 on the course.
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jmoote said:
Stiffness is the main reason. Not to be confused with strength - so a stiff bar might help your sprint on the road, but in cross likely makes no difference. The lighter weight of carbon bars makes no difference to the road pros since their bikes are all under the UCI limit anyway. On your average cross bike, it is a nice way to save 70g.
I don't buy that racers on >30 PSI 32-34Cs are worried about their bars being too stiff. :skep:

Wells was in the minority last season with his choice of a carbon fiber handlebar but jumped on the bandwagon for '08 with a more conventional KORE Road Elite model made of 7075 aluminum. Though he likely misses the carbon bar's 50g weight savings, the aluminum bar's durability advantage and grippier surface was apparently enough to justify the switch.

"The aluminum bar is new for a few reasons," Wells said. "I had problems with my levers slipping down on the carbon bars on really rough courses. No matter how much I clamped the levers down they would slip sometimes when sprinting on the hoods in bumpy grass. Also, in cross it's easy to crash and with carbon bars they are more likely to break than with aluminum bars. In addition to all that, with all the travel the aluminum bars seem to hold up better then the carbon."
http://www.cyclingnews.com/tech/2008/probikes/?id=todd_wells_gtr_typecx08
 

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Anti-Hero
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Discussion Starter · #10 ·
OnTheRivet said:
I don't know, there has to be a reason almost no road pros run carbon bars/stems.
Because if you wreck and your bars bend, you can probably hop back on your bike and finish. If you wreck and your bars break, you have to wait for a spare bike or quit.

I'd hazard a guess that falling is more commonplace in CX (though typically at a slower speed). That's how this bar met its end- barrier crash.
 

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veldrijder
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PeanutButterBreath said:
Than again, it doesn't sound like stiffness is a priority for pro roadies either. :confused:
No? They seem to cite that reason pretty consistently when asked why they run aluminum stems and bars. Obviously it would be more to the sponsors liking to run the swanky carbon stuff, so they must feel pretty strongly about it.
 

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After landing on my bike in the barriers because my teamate stacked it my Al Salsa bars met my steel toptube of my Ritchey Swisscross. My toptube dented, bars didnt. Was able to finish the race for 4th. If I had CF on either side, 1) I would be out alot of cash and 2) Have a DNF instead of a 4th

I'd rather run Al stems and bars and replace each year and know my stuff is solid than continue to run CF bars after crashes.

Just my .02
 

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Devoid of all flim-flam
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Why doesn't somebody make a carbon bar that'll survive a crash? Isn't carbon supposed to be so workable you can do practically anything you want with it?
 

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Mapei said:
Why doesn't somebody make a carbon bar that'll survive a crash? Isn't carbon supposed to be so workable you can do practically anything you want with it?
A CF bar that is as tough as tough as aluminum would likely lack the weight advantage (razor thin as it is) and ride quality (as ephemeral as that is) to attract buyers.
 

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jmoote said:
No? They seem to cite that reason pretty consistently when asked why they run aluminum stems and bars. Obviously it would be more to the sponsors liking to run the swanky carbon stuff, so they must feel pretty strongly about it.
I'm lost. What do they cite about which? CF bars are neither necessarily lighter nor stiffer. The only reliable difference is price.
 

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Overtaxed RBR member
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I have never broken a carbon component. I have broken 2 aluminum mtb frames, 1 aluminum mtb bar, a Look pedal axle and have toasted numerous mtb wheels and a rear Ksyrium-all aluminum. I have been riding Zipp wheels for a long time without a problem. I crashed extremely hard on a Trek OCLV mtb in a race. The XTR brake lever hit the top tube hard enough to bend it to almost a 90 degree angle. The only damage to the frame was missing paint-no cracks or scratches. I had to put the lever in a vice to bend it back. Shimano alloy is very tough.
I think a lot of carbon failures occur from people over tightening parts like brake levers.
Also, if you are 200lb, don't ride ANYTHING light weight. You are just asking for it.
 

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ridenfish39 said:
I crashed extremely hard on a Trek OCLV mtb in a race. The XTR brake lever hit the top tube hard enough to bend it to almost a 90 degree angle. The only damage to the frame was missing paint-no cracks or scratches.
The problem is that a CF component can be terminally damaged without displaying any visible cracks or scratches. If the frame were metal, you would be able to tell whether the tube had been pushed beyond its limits. With CF, the damage may only be visible on the inside of the tube, or not at all.

A lot of CF parts do break because of improper installation. If you look at the linked-to pictures you will see that this was not the case.
 

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Cowboy up
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I saw someone break their carbon post at a cx race this year. Fortunately no injuries since she was running beside the bike when it came off. A broken seatpost is scary given the proximity to the femoral artery.

From Competitive Cyclist on why pros use aluminum and recommendation to replace carbon bars after your bike tips over.

The answer is rather easy: Pro mechanics are big believers in due diligence. They know that if one of their riders crashes (and they all do), or if they accidentally drop or tip over a bike when loading it or unloading it, the handlebar takes the brunt of the force. In either situation prudence requires at the very least that you unwrap the bars, remove the STI or Ergo, and remove the stem to closely inspect the bar to ensure that no micro-cracking occurred as a result of the mishap. Such due diligence, of course, is an enormous pain in the ass, and sticking with an alloy bar that weighs in at 20g heavier is the sensible solution.

http://www.competitivecyclist.com/za/CCY?PAGE=FAQS#ques_42

After a road crash I would think they would replace AL bars too regardless of visual condition.
 
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