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Hello all,
I am in the process of selecting a new stem and bar for my newest bike. What are the pros and cons of the 31.8 bars. I assume they are stronger.
New bike currently is running a low rise CF bar and a 0 degree stem. Puts my bar about 2" below the seat. I am looking to get it about even with the seat height so I'm thinking 6-10 degree stem with a higher rise bar should do the trick.
There are some good prices out there on 25.4 CF bars but if 31.8 is going to be more of the standard then for once I can be ahead of the curve. I weigh in @ 200 with pack and ride mostly XC type stuff. Thanks for the help!
 

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bigger diameter is stronger. I switched to a wider bar, and they only come in the 31.8 size. That should tell you something.
 

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cabinfever said:
Hello all,
I am in the process of selecting a new stem and bar for my newest bike. What are the pros and cons of the 31.8 bars. I assume they are stronger.
New bike currently is running a low rise CF bar and a 0 degree stem. Puts my bar about 2" below the seat. I am looking to get it about even with the seat height so I'm thinking 6-10 degree stem with a higher rise bar should do the trick.
There are some good prices out there on 25.4 CF bars but if 31.8 is going to be more of the standard then for once I can be ahead of the curve. I weigh in @ 200 with pack and ride mostly XC type stuff. Thanks for the help!
31.8 will be a little stiffer and a little lighter, but will all your handlebar accessories fit (computer, etc.)?
 

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Usually it's just the part near the stem that's wider--the bar tapers to smaller size as it goes out, so there should be plenty of room for computers--they fit fine on my bars.
 

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Elitest thrill junkie
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One con of the 31.8 bar is the gradual-taper that makes it difficult to put your brake levers/controls further in, and while the goal may not be to move your hand placement closer in, putting the brake levers in enough so that you just grasp the end of the lever for maximum leverage is kind of important and a good idea, so it can be difficult to get this control-position with some 31.8 bars due to the taper, and then you have to go to an even wider bar than you'd have with the 25.4.

I highly doubt the 31.8 bars are lighter, if anything manufacturing and materials have caused bars to be slightly lighter, but the size probably makes no appreciable effect.

I have both right now, and I wish the 31.8 had a steeper taper to maximize the area where you put the controls and grips.
 

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New Bike 31.8 all bar/stems I have 25.4

I know the feeling, my new bike has 31.8 bars and all stems and bars I have are 25.4.

There's a way bigger selection of lower priced 25.4 bars and stems out there.
With handle bar rise being another way to get a more upright riding position, again the 25.4 wins out as having a greater selection of rise and sweep.

I'm trying to dial in my position on this new bike and it has become a pain.
I bought a different 31.8 stem to try, and have started down that road (trail) because changing stem/bar involves transfering levers, grips, etc.

Another consideration becomes cables and Hydraulic brake lines when changing to a more upright riding postion.
Try sitting on the bike and holding the bar in the position you are after.
This will show whether there is enough cable/hydraulic line to get there BEFORE you buy anything!

And as far as the strength/stiffness argument goes....have you ever broken a handlebar or know anyone who has?(marketing hype in my opinion)

Tilos
 

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Founder: Dirty3hirties
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31.8 bars evolved because of the trend towards more aggressive riding. If you're riding mostly XCish terrain, a 25.4 bar will be fine...even if you're 200 lbs with gear. Riders have been using the same 25.4 bars for DH, FR, for years w/o any problems. The 31.8's will be stronger of course, but heavier for sure...they're built to take more abuse. If you have your mind set on the 31.8's, get it....but it won't make a difference to your riding IMO. If you're concerned about carbon, it has been proven that carbon bars are stronger than AL bars (crash damage is different).....but as far as fatigue strength, carbon bars are much stronger.

I'd get the bar that best suits my fit...meaning I recently bought an AL bar because it had the rise, sweep and width that I wanted...didn't exist in a carbon model. AL is much harsher though....and don't overlook this. It's a huge difference. If you find your preference in both makes, then it's just a matter of whether or not you want the added bling factor of carbon and the damping qualities it provides.
 

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Tilos said:
And as far as the strength/stiffness argument goes....have you ever broken a handlebar or know anyone who has?(marketing hype in my opinion)

Tilos
Gonna have to suggest that you do a search. In my opinion this is not the manufacturers fault as everyone demands light bars... that is until this happens.



Courtesy of Endomaniac.
 

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Same Question

gunit said:
Gonna have to suggest that you do a search. In my opinion this is not the manufacturers fault as everyone demands light bars... that is until this happens

Have you ever broken a Handlebar or know someone who has??
No search required to answer.
Tilos
 

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I snapped a steel handlebar off my Canadian Tire bike; that wasn't too nice. From what I can tell, an equivalent bar from the same manufacturer in 31.8 vs 25.4 ... the 25.4 is always lighter (at least, for the CF ones). As an added bonus, the stems are generally lighter too.
 

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gunit said:
Gonna have to suggest that you do a search. In my opinion this is not the manufacturers fault as everyone demands light bars... that is until this happens.



Courtesy of Endomaniac.
That's a nasty pix for sure but no one will argue that handlebars can/do break....everything can if enough force is applied. If a manufacturer's ultimate goal was to make the lightest bar while sacrificing strength to the point of it being unsafe for "normal" riding (which is what you're implying) then you would hear about MANY more failures and the company would surely find itself in court. And the trend is definitely the opposite of "let's make it as light as possible" since more manufacturers are coming out with 31.8 bars which are inherently heavier. Just because this particular pix shows a failure doesn't mean it's something to worry about incessantly. And from the looks of the pix, it must have been a really bad crash because even the TT is bent out of wack. I'd like to know what kind of crash that bike was involved in to do that amount of damage.
 

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I'm SUCH a square....
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When I was building up my last bike, I came to 2 choices for a bar -- $110 Monkey Lite CF, or a $30 RaceFace Evolve AL. The Evolve was 31.8, the Monkey was 25.4. I too have a collection of 25.4 stems, even a couple bars, but they were 'gifts', and did not put me in the position I wanted on the new bike.

I've been rolling the Evolve for a year and a half now; a little flex outside the riser bends, but a good setup. Having ridden both, I can say that the INITIAL stiffness is there -- the bar/stem interface is a rock! Steering is there, and I just look at the small amount of flex as 'a touch of cush'....
 

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ddraewwg said:
That's a nasty pix for sure but no one will argue that handlebars can/do break....everything can if enough force is applied. If a manufacturer's ultimate goal was to make the lightest bar while sacrificing strength to the point of it being unsafe for "normal" riding (which is what you're implying) then you would hear about MANY more failures and the company would surely find itself in court.
That is kind of what I am implying, yes. There is selective pressure created by us for ever lighter components (evolution of sorts). Any time someone asks about a new bar one of the first questions is how much does it weigh. :nono: Moreover, the lighter a product is the more companies can charge for it... less material, higher price, go figure. :thumbsup: I do not think that companies purposefully make dangerous equipment in general, but they do play the law of averages.

The reason that companies do not find themselves in court is because most people understand that mountain biking is a dangerous sport, and expect failures to happen. We should use our brain and select appropriate equipment for our style of riding. That being said, if the selection is appropriate, critical components should NOT undergo sudden failure. We must adjust our expectations, this is poor engineering.

ddraewwg said:
And the trend is definitely the opposite of "let's make it as light as possible" since more manufacturers are coming out with 31.8 bars which are inherently heavier.
The trend that you mention is not magical, nor is it an action of our benevolent masters. Rather, we have started to realize that light is not always right.

ddraewwg said:
Just because this particular pix shows a failure doesn't mean it's something to worry about incessantly. And from the looks of the pix, it must have been a really bad crash because even the TT is bent out of wack. I'd like to know what kind of crash that bike was involved in to do that amount of damage.
The bar in question broke after a 4' drop, it was not the result of a crash. The top tube was crafted cruiser style.
 

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bigpedaler said:
I've been rolling the Evolve for a year and a half now; a little flex outside the riser bends, but a good setup. Having ridden both, I can say that the INITIAL stiffness is there -- the bar/stem interface is a rock! Steering is there, and I just look at the small amount of flex as 'a touch of cush'....
Just so you know, aluminum that flexes is aluminum that will fail suddenly, each flex is one step closer. Steel can flex within a given range and be just dandy "forever."
 

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"less material, higher price, go figure"

Perhaps this added cost of light components is to cover additional liability insurance!

Without getting into tube forming or the engineering aspects of handlebars, I would agree that CF has a greater elastic limit than work hardened or heat treated aluminum.

I have never cross sectioned a CF handlebar but have seen an aluminum inner sleeve in many a CF seatpost.
This would imply to me that a 31.8 CF handlebar has an aluminum sleeve in the clamp/stem area.
Has anyone ever cut up a CF handlebar??
Oh, and as a side note, the CF weave pattern finish of most rigid road bike forks and seatposts is simply a "decal" or overlay for cosmetics, not an indication of hand or machine laid mesh material.
Tilos
 
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