i was thinking of putting FSA carbon K wings on my 'cross bike this fall. most of my mountain buddies laughed and said see you in the e.r. anyone out there have luck withthem or is this just a really bad idea? i tip the scale at 185. and tend to ride my cross bike like my mountain bike, agressive in corners and down technical areas. thanks for any advice.
carbon bars or a trip to the e.r.
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I don't think there is anything inherently dangerous about carbon bars, but on a cross bike? What is the point? There is no point being a weight weenie, and why do you need wings?midget said:
If you want to be different, use moustaches.
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I doubt anyone is building
wide carbon road bars built to handle the vertical loads of riding off road on a rigid bike. Vertical stress on a cx bike's front end is divided between the wheel,the fork, stem and bars. since the area of highest leverage is the bars this is a focal point of stress.
this is not where you want failure to occur.
wide carbon road bars built to handle the vertical loads of riding off road on a rigid bike. Vertical stress on a cx bike's front end is divided between the wheel,the fork, stem and bars. since the area of highest leverage is the bars this is a focal point of stress.
this is not where you want failure to occur.
the point is i have them and i like them. wings because of the fact that i like them and i have them. if i wanted to be different i would be someone else. thanks for the insults and offering no real answer or insight.filtersweep said:
have you known anyone to use a bar such as this? your insight echoed my thoughts. i have also thought of the aluminum version. i tend to like the shape. any thoughts on the structural integrity of the aluminum bars. i am assuming they are stonger, and that failure would not be so catastrophic. i guess i just answered my question.atpjunkie said:
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Actually, fiter did provide insight.midget said:
1) Carbon bars aren't dangerous on the road, but for cross, who knows? They weren't designed for cross.
2) What's the point? What are the real advantages? I can't think of many.
3) Weight doesn't matter on a cross bike all that much. You are certainly welcome to differ. I don't think the few grams a carbon bar may save are worth it, then again, I don't think super-light al bars are worth it for cross either.
Sure some pros might run carbon bars, but how often are they replaced?
ATP explained the reasons not to run a carbon bar.
Let's put it this way, a carbon bar fails a benefit/cost analysis (now, so too do lots of little high-end toys on bikes, but that's another discussion). Add in the risk of breakage on a part that you really don't want to break when you are on a bumpy drop-off, and it's a no brainer if you ask me.
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Failure mode for carbon
As already mentioned the failure more for carbon tends to be all at once and catastrophic. Failure may occur as a function of a stress riser such as a deep scratch, which is very concievable since it is not uncommon to slide out the front on a cross bike and ding the bar, but also is a function of carbon being non-anisotropic i.e. responding to stress differently depending on the orientation of the part to the froce applied. One of the biggest stresses I have noted with aluminum bars on my cross bikes concerns the stress placed on the right side of the bar when remounting from the left. I remember some really nice Specialized bars(made by Nitto I think) where the right side of the bar gradually bent inward with repeated remounting. With a carbon bar - especially one that is flat on the top, I would think thee could be a possibility of a catastropic failure under those same forces - unless the material was specifically laid up is such a way to accept that force.
Finally, I think the shape would be a pain to mount top mounted brake levers, if it was possible at all.
John
As already mentioned the failure more for carbon tends to be all at once and catastrophic. Failure may occur as a function of a stress riser such as a deep scratch, which is very concievable since it is not uncommon to slide out the front on a cross bike and ding the bar, but also is a function of carbon being non-anisotropic i.e. responding to stress differently depending on the orientation of the part to the froce applied. One of the biggest stresses I have noted with aluminum bars on my cross bikes concerns the stress placed on the right side of the bar when remounting from the left. I remember some really nice Specialized bars(made by Nitto I think) where the right side of the bar gradually bent inward with repeated remounting. With a carbon bar - especially one that is flat on the top, I would think thee could be a possibility of a catastropic failure under those same forces - unless the material was specifically laid up is such a way to accept that force.
Finally, I think the shape would be a pain to mount top mounted brake levers, if it was possible at all.
John
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and people always toss in the
carbon MTB bar argument failing to recognize that most of the vertical load is absorbed by the suspension fork. I'm sure no mfr is doing any CX CF bars.It would mean that the CF layup (fibre direction) and thickness would be designed into the bar to deal with such loads. again any slight knick and you've compromised the piece and if it goes so do you.
There are few things more painful in cycling than bar failures at speed.
Pro's use them, because they get them for free, replace them often and have a mechanic to keep an eye on them. If you have all of those things covered, by all means go ahead.
I'm with euro and do cost /weight analysis. I'll err on cheap, strong and heavier any day.
carbon MTB bar argument failing to recognize that most of the vertical load is absorbed by the suspension fork. I'm sure no mfr is doing any CX CF bars.It would mean that the CF layup (fibre direction) and thickness would be designed into the bar to deal with such loads. again any slight knick and you've compromised the piece and if it goes so do you.
There are few things more painful in cycling than bar failures at speed.
Pro's use them, because they get them for free, replace them often and have a mechanic to keep an eye on them. If you have all of those things covered, by all means go ahead.
I'm with euro and do cost /weight analysis. I'll err on cheap, strong and heavier any day.
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actually, Schmolke will do a CF bar for your CX rig, handmade to your weight etc. Though, they cost like $400. Grams saved vs $ spent not worth it. A TTT Prima 199 weighs 199 grams and the Deda 215 weighs 215----thats a good weight, and those bars are cross tested.
jeremy
jeremy
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I think that, for the most part, carbon bars are fine for cross. I think that most modern carbon bars can withstand the rigors of regular cross racing and aren't probably going to just break for no reason. That said, as soon as you crash on a carbon bar that all goes out the window- this goes for road and cross since road crashes are usually harder on gear since you're going faster and crashing on pavement. But for 'cross, I tend to crash more frequently and all it takes is a good one on the bar just right and the clock starts ticking. Who knows when it's just going to snap after that? It's very hard to see certain types of cracking and damage on crashed carbon parts (compared to aluminum). After spending $250+ on that bar are you really going to retire it after a crash? Probably not. So after that point you're riding around just asking for it. When you talk to someone who has broken a carbon bar while "just riding along" always ask if it was ever crashed (even "lightly"). Almost all the times I've seen bars break and asked people this, they will admit that it had been crashed at some point (or they bought it used- never buy used carbon parts) but the person just looked it over and thought it was ok. I also think that wing shape is inherently weaker, especially for the aluminum versions.
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