bsyptak

I've got a Specialized carbon handlebar on my 04 Stumpy and every so often I imagine going through a rock garden or somesuch other nightmare and having my carbon bars fail for no reason. The image is of me eating my Thomson stem with my teeth.

Do you trust your carbon bar indefinitely? Any evidence that I shouldn't? I'm sure I've dumped the bike a few times, though not sure what if any hit the bars have taken. I'm thinking about stepping up to a 31.8 stem/alloy bar combo since my setup is a 25.4 anyway.

junkyard

I don't trust anything indefinitely.

grudgemonkey

This has nothing to do with carbon, but 31.8 should be outlawed.

rankin116

Any reason for that?

Chris_F

I think the best you can do is take the bar off and inspect it periodically for cracks.

Rutnick

because he doesn't realize that the 31.8 is actually stronger but hey...he's partying like it's 1990s.

grudgemonkey

It might be stronger, but it's overkill. How often to 25.4 handlebars break or bend when their 31.8 counterparts would have survived?

For road bikes, the larger radius can add comfort. For XC and AM riders, there is no real benefit.

bsyptak

I do realize that 31.8 is stronger and I would go there if necessary. But I prefer not to spend the money to replace my s-works carbon bar & Thomson stem with new stuff unless it's really necessary. But if the consensus is that people replace carbon bars every X years as a rule, then I would go ahead and get a new 31.8 stem at the same time and be even more sure.

I think that the handlebar is the single worst component to fail on a bike. Your entire upper body is relying on the bars being there. If they fail, you're going down and hard. Unless you get lucky and your wheel turns and throws you sideways into who knows what, you'll go down right onto your stem and broken bars. That would not be good.

Chris_F

Is there a potential, with the added strenght, to make the bars lighter?

grudgemonkey

Typically 31.8's are a little heavier.

Maelstrom 

Ditto, there is no such thing

Rutnick

wrong

bsyptak

I think the s-works bars on my bike now are 160g (claimed). Specialized has a 31.8 alu bar that is 208g claimed and $40. Their 31.8 carbon bar is 195g so negligible. Hard to beat on price and weight. Anybody know anything lighter?

Cheeto

Carbon fiber is stronger than steel, or so they say. It is fine, until the Resin that holds it's integrity is cracked or chiped, then that becomes the weak point of the bar.
I'd say if you're truly bothered by the horrific images of your teeth becoming a thompson stem, then Inspect the handlebars throughly. try looking at all different angles in different lighting to make sure there are no cracks, chips, or stress marks/fractures.

troie

$40 for a carbon bar? Show me.

bsyptak

"Specialized has a 31.8 alu bar that is 208g claimed and $40"

But, OK: https://www.performancebike.com/shop/...tegory_ID=5250

the riser one is $60 today, but tomorrow or the next day it'll be $40 and this one will be $30. I actually bought the flat bar one a few years ago for my hybrid commuter and it works just fine. Seems like I paid low $20s for it after all the discounts and such.

gfrance

I never even think of my carbon bars. I guess I trust them enough.

scelia

Thomson

grudgemonkey

You have failed to answer how often 25.4 handle bars bend or break in situations when 31.8's would not.

Additionally no benefit for XC or AM riders was shown by your eloquent post.

Cheeto

I know i know, I ride their damn trail.... at their factory.

I must of got happy fingers, and hit the P.

scrublover

Have had two carbon bars, neither of which failed. An older IRD Mosaic. Nice bend/sweep, sold the bike it was on, a rigid XC hardtail. Recently tried Titec carbon riser. Snap, crackle, pop noises greeted me from the very first.

Double checked that it wasn't overtorqued, checked for cracks and so on. No grease. No overtightening of the levers/grips/shifters. Had a local shop take a look as well, just to be sure I wasn't missing something. Nothing was slipping/moving that I could find, either. Maybe it's fine, but the noise annoyed and worried me enough that I found myself not trusting the damn bar. I hate that. It impinges on riding joy. No cracks or anything found upon removal.

Maybe it's only making nose, but it annoyed the hell out of me. Swapped back to an alu bar: Sunline V-1 OS. Great feel, bend, and sweep. Looooooove the width. It's quiet. I"m much happier, and don't give a rats ass that it's slightly more weight.

Dannihilator

My 31.8 gravity carbons are very light compared to what I used when I had 25.4, and trust them alot more.

xcracer13

I trust them, I don't go any easier on them than I do on aluminum bars. Just check em' every now and then for cracks

grudgemonkey

https://www.eastonbike.com/PRODUCTS/BARS/bar__top.html
https://www.raceface.com/components/handlebars/
https://mtb.fullspeedahead.com/fly.as...duct&taxid=141

When you compare any of the above manufacturers, the 31.8 version is always heavier than the 25.4.

So when I say, "Typically 31.8's are a little heavier.", I am correct.

Sorry, no stairway to fail.

kenhill3

I used a carbon Scott LFX (120 grams) straight bar on my hardtail for 8 years or so, no problems of any sort. I still have that bar and would use it again with no hesitation. My current hardtail has a straight FSA carbon and my FS has a Raceface carbon. I trust these bars.

A lot of people seem to fear catastrophic breakage of carbon bars, as if any little nick or scrape will propagate into full blown failure. I have yet to speak with ANYONE who has experienced this. CF does not snap off, as far as I know. While it can indeed fail, like in a crash, the fibers and resin still somewhat hold things together in a mushy kind of way. I know this from experience because I've ridden out of the woods with a mushy bar.

Now, aluminum is a material with a potential for catastrophic failure, gouges, scratches and stress risers being the causes and precursors to breakage. Many people who ride hard will replace aluminum bars every two years or even yearly depending. Aluminum indeed has a limited fatigue life (cycles to failure). Carbon fiber is known for it's very high/extended fatigue life. There must be something good about it if The Boeing Company is building it's Dreamliner out of the stuff.

Edit: To the OP, I probably would not trust CF bars INDEFINITELY, but, geez, I would for quite a while, barring any bad crashes.