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Discussion Starter · #1 ·
I have been ridding a pair of Easton Monkeylite carbon bars 25.4” matched up with a Thompson Elite stem for about 11 years now. Although they show no signs of fatigue I am concerned about them failing. If …ok when I do replace them should I go with the now more standard wider 31.8” bars? If I do go the wider diameter I know I’ll have to swap out the stem to match, but what about the break levers, bar grips, bar ends and shifters? Won’t all of those components need to be swapped out as well? If so this is going to be fairly costly as I run Hope brakes with the reservoirs mounted on the break levers.

Is it worth going with the 31.8” diameter and new carbon bars, or just replace my old ones with an aluminum 25.4” bar?? Thanks – Joe

Riding style if there is such a thing, XC rider, 200 pounds, non racer, running about a 5 1/2” travel bike.
 

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jmpilo said:
I have been ridding a pair of Easton Monkeylite carbon bars 25.4" matched up with a Thompson Elite stem for about 11 years now. Although they show no signs of fatigue I am concerned about them failing. If …ok when I do replace them should I go with the now more standard wider 31.8" bars? If I do go the wider diameter I know I'll have to swap out the stem to match, but what about the break levers, bar grips, bar ends and shifters? Won't all of those components need to be swapped out as well? If so this is going to be fairly costly as I run Hope brakes with the reservoirs mounted on the break levers.

Is it worth going with the 31.8" diameter and new carbon bars, or just replace my old ones with an aluminum 25.4" bar?? Thanks - Joe

Riding style if there is such a thing, XC rider, 200 pounds, non racer, running about a 5 1/2" travel bike.
Only the stem clamp diameter is different. The grip and control diameter is the same.

If your levers are broken, you should replace them, though.
 

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11 years?

I'd replace the bars. That is a lot of use for a flexible piece of material. Further modern carbon fiber has been more thoughtfully utilized with an eye to layout style. Think of it as an opportunity.
As to the larger clamp diameter? I have never had a problem with breakage nor have I ever seen a bar break due to diameter issues. Actually in 25 years I have never actually seen a bar broken. I know it happens but I've only seen pictures here on MTBR, and very few at that.
 

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utilikilted
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I put 31.8mm Monkeylites on a bike of mine about 5 years ago. I researched long and hard in considering carbon. There were plenty of stories of carbon bar failure on the internet at the time - I haven't checked lately. I based my decision on the increased stem diameter and the fact that I only weigh 165 lb. I tightened the stem with a torque wrench. Though I ride aggressive rocky singletrack and like to descend fast, as most do on this forum, I don't huck - 3' drop offs are my limit. If I were choosing between carbon and aluminum today and my riding was more in the freeride category, I would be back to researching the latest breakage info out there - even more so if I weighed 200 lb. A consideration is in the 11 years you have had your current handlebar, has your riding improved? If so, that also will cause more stress on your components.
 

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on your left
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Discussion Starter · #8 ·
Thanks for all the input on this thread. Really glad to hear that the grip and controls are the same diameter. I've had these bars on three frames over the years & think its about time for a change. I've heard repeated stories of the bars failing causing catastrophic results over the years. Actually what prompted this thread was that i was speaking with my bike mechanic the other day & he mentioned that one of his friends had to life flighted off a trail when his bars failed. I highly respect this person's opinion. But i have to say, based on my experience I have nothing against carbon bars and am strongly thinking about replacing mine with a stronger 31.8" carbon pair and matching diameter stem. Although ......I am pushing 200 lb's now, but if anything have become a less aggressive rider (& skier) over the years - in my 50's now. Thanks again for the input:)
 

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Don't Tread on Me
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Carbon fiber bars have an almost infinite service lifetime, certainly longer than aluminum. Would you think about replacing 11 year old aluminum bars? The carbon fiber bar is no more likely to fail today as it was the day you installed it. Every carbon bar failure I have heard of resulted from one of two causes but the same reason. Either the bar was destroyed during installation by some ham fisted wannabe mechanic, or the bar was damaged by an impact. In either case the carbon fiber matrix was compromised.

Most early bad press about carbon bar failures were perpetuated by guys who had just spent lots of money on a product and then destroyed it in seconds in the act of installing it on their bike. No one wanted to admit they had made a mistake. The most ignorant of them rode the bars even after they heard the snap, crackle and pop, or saw that they had wrecked the bars during installation by their own ignorance. The guys who really had a legitimate beef were the guys who paid to have the bar installed and then had it damaged by the installer.

After proper installation, flexing the bar during riding (regardless of riding style, experience, rider weight) will not compromise the carbon bar matrix integrity no matter how many times the bar is flexed.

Carbon bars should be carefully inspected after any crash where the bar could have impacted the ground or any object. Any dent or obvious deformation of the bar means the bar is toast. Never ride this bar again. If the bar is scratched, inspect to determine how deep the scratch goes. If the matrix of the carbon fiber is damaged, either at the impact site or at any point of attachment, the bar is suspect and should not be trusted. If the scratch proves to be superficial, the bar is still just as trustworthy as it ever was.

One disturbing fact about a carbon fiber bar failure, is that the bar will not usually provide a sensory warning that it is about to fail. It will simply fail. In contrast, an aluminum bar may flex past its normal travel range but still remain in one very much weakened piece.

Your 11 year old carbon bar is actually just as safe or safer than any newly installed bar. It has, after all, proven itself many, many thousands of times. It will not weaken and you will likely not live long enough to ever cause it to fail by normal use. Everything I have stated is in my opinion and if you still decide to replace your bar for a reason other than logic or common sense, I'd like to pay for shipping and postage to have you send it to me so I can put it to good use on one of my bikes.
 

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Discussion Starter · #10 ·
Thanks Lopaka, I couldn't agree more with all of your points especially your reference regarding carbon bar failures vs. aluminum, were as aluminum is more likely to give you a bit of a warning. My thoughts were that the larger diameter carbon bar may provide a bit more strength. And that over the years I may be missing a fatigue point with my carbon bars.

Lopaka said:
Would you think about replacing 11 year old aluminum bars?
Yes I would definitely consider replacing the bars if they were aluminum as i have done so over the years on my other bikes. In my opinion with aluminum bars its much easier to detect failure points, IE dents or bends. I am also a big believer in if "it's not broke don't fix it", but as Shiggy mentioned, the seed of fear has been planted. Maybe I'll rethink my position on replacing these bars.........
 

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Lopaka said:
Carbon fiber bars have an almost infinite service lifetime, certainly longer than aluminum. Would you think about replacing 11 year old aluminum bars? .
The application of carbon fiber technologies have improved a great deal since 2000. Perhaps you can recall discussions here at that time.
 

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Lopaka said:
Carbon fiber bars have an almost infinite service lifetime, certainly longer than aluminum. ...
The sun significantly weakens CF over Aluminum.
I don't know if this is the case w/ the OP - but still - thought I should point that out
 
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