Carbon Parts

[ThinkFast]

I was wondering which parts are best to stay away from going with carbon. I had a few people tell me I should stay away from having a carbon seat post and I continued using one any way. Well today I noticed a large crack in my carbon seat post. Luckily I noticed it instead of having it fail while I was out on the bike. So it has me wondering which parts might be best to keep away from carbon.

Thanks.

[Neccros]

I dont like carbon for MTB'ing... but thats just my fat a$$ talking

[CeeDubb]

You have to figure out what you're looking for and what type of riding you're doing.

Balance out durability vs. weight. I don't see very many carbon fiber parts on downhill and hucking rigs.

If you're looking for a lightweight XC machine and you're not looking to huck or fly over every little thing you see, you'll be pretty safe on whatever carbon fiber goodie you get.

The main parts that people have a concern with are handlebars and seatposts. They both take a beating on whatever bike you get and when you actually compare the weight savings between CF and aluminum, it's not all that much.

You may be concerned if you're a big guy, too.

Whether you get carbon fiber or aluminum, be sure to inspect your ENTIRE bike on a regular basis. I've seen frames crack long before the CF parts do....

[DownhillWebKook]

If you are built like Shrek and ride like Stone Cold Steve Austin, then I suggest avoiding anything made of carbon fiber.

If you are built like Shrek, but ride like...ummm...Nuryev (Russian ballet dancer), then you can probably get away with some carbon.

On the other hand, if you're very light and/or have a pretty smooth style or ride fairly mellow terrain, you can get away with more carbon.

I run carbon bars for dh and mtx without problems. I am 180, 6'4" and tend to absorb impacts with my long arms and legs and put less stress on my bike as a result. So, carbon works out pretty good.

I think the seat post is kind of sketchy though. I don't know why, but it seems like a problem area where you have inconsistent loading and friction. The handlebars seem to perform in a more distributed load bearing role where the force is spread out more.

Oh, but I did disintegrate my XO Black Box carbon rear der. recently. It just got shredded into nothing. Bummer. I have since switched to X9.

Cheers,

[Schecky]

I love my carbon bar, but for the vibration dampening, not weight savings.
Carbon is plenty strong for this clyde.

[Waldo]

I'm with CeeDub: The weight savings, versus durability issues versus cost just don't add up for my purposes. The exception might be handlebars, where good carbon & aluminum bars are pretty similar in price and the vibration damping qualities of carbon hold some appeal.

CeeDub also makes a great point about inspection. We should all inspect our bikes regularly, but I think even more so if you run a lot of carbon. I recently ditched a set of carbon bars when I found an almost imperceptible crease where the stem clamped on. If I hadn't had the bars off, and hadn't taken the time to check them carefully before re-installing, that could have been ugly. For the same reason, I don't see myself ever running a carbon frame. The risk of a rock strike or some other impact on the downtube leading to frame failure just don't seem worth it.

Any part can/will fail, but for the money I'll go with aluminum more often than not. Carbon has it's place, but for me it's pretty limited.

[CeeDubb]

Don't get me wrong...my next bike will probably be a 2008 S-Works Epic. I'm gonna try to get that mamma jamma under 23 lbs.!! Carbon fiber galore!!

Liam Killeen's Team Specialized S-Works Epic Carbon

[Edog]

I love my Monkey Light Carbon bars, they have been super strong, I've used them for pretty some agressive riding, I weigh nearly 200 with gear. I got them on sale for $70 with was the same price as the Al version. I'm sure somebody will elaberate on this but shouldn't you change out carbon parts every 3 years or something?

[andy aka rut]

My roommate (Burdman) would suggest staying away from carbon handlebars. He broke his bars while on the Fullerton Loop. What else did he break because of the bars??! Only his clavicle, 3 vertebrae and 2 ribs. Of course the bars were a couple of years old, but still... ouch!

He is about 5' 10" and about 150lbs.

[CeeDubb]

Originally Posted by mechmann

it is important to note that for equal weight items in the handlebar department, the carbon will be WAY stronger. just something to remember. light aluminum bars fail too

Very true. However CF doesn't fare as well after impact as other materials. I've seen CF fail and it does so dramatically and catastrophically.

[Dino Brown]

I run Race Face Carbon bars! Love them. Still make me a bit nervous though!

What makes me nervous? Carbon snaps! Aluminum is the more "likely" (of the two) to bend before breaking. One good "SCRATCH" and you run the risk of catastrophic failure...

The reason I like Race Face over Easton- RF has a clear coat finish! In my opinion: 1) an added layer of protection 2) easier to visually inspect for scratches!!!

P.S.- Andy (aka Rut) is my Hero! Long Live The King!

[DownhillWebKook]

No single formula here, really. There are numerous factors. The best carbon bars on the planet are rendered to sh!t if you apply to much torque on the stem clamp. Neglect can also lead to similar results. Hucking and landing like a grand piano from a 15th story window is probably going to produce some issues, too. Bottom line: carbon is Gucci. I like Gucci.

[BrewMaster]

Originally Posted by mechmann

the most common cause of carbon failure is over torquing.

aluminum can fail in the same catastrophic manner as carbon.

no material is perfect

Very true, but they have different failure modes. As we (my company) design more and more carbon fiber-based parts, we have found that maintenance and repair is much more critical on composite parts than on metal parts. We are working primarily in the aerospace industry, so catastrophic failure is not an option.

Metals are inherently more durable and require less general maintenance, but they are certainly not failure proof.

[CeeDubb]

Originally Posted by mechmann

the most common cause of carbon failure is over torquing.

aluminum can fail in the same catastrophic manner as carbon.

no material is perfect

Okay...okay...

So when I get my new XTR cranks with the CF middle chainring, I should have a cause for concern?

You know how much torque I generate when mashing them gears?

87 Watts of pure unadulterated power baby!!

I'm gonna be crackin' chainrings!!

[SSinGA]

Originally Posted by CeeDubb

Okay...okay...

So when I get my new XTR cranks with the CF middle chainring, I should have a cause for concern?

You know how much torque I generate when mashing them gears?

87 Watts of pure unadulterated power baby!!

I'm gonna be crackin' chainrings!!

FWIW...the XTR middle ring is Ti with carbon ramps for the chain.

[Keith B]

My Easton EC90 SL Monkeylites survived a close on 30mph impact into a tree. Easton asked for the bars back to strength test and gave me a brand new bar in its place :-) The impact on the bars was strong enough to shear the aluminum brake lever mount in two so I have no concerns about using Easton grade carbon.

[CeeDubb]

Originally Posted by SSinGA

FWIW...the XTR middle ring is Ti with carbon ramps for the chain.

True...true... the middle chainring's entire core and teeth are titanium and the shell (with molded ramps) is a carbon fiber composite.

I'm gonna be crackin' titanium, too.

[SSinGA]

Originally Posted by CeeDubb

True...true... the middle chainring's entire core and teeth are titanium and the shell (with molded ramps) is a carbon fiber composite.

I'm gonna be crackin' titanium, too.

Cost on the replacement is $70+ I can't imagine waht retail will be I hope it lasts a while.

FWIW...if you're in the market for some Shimano parts, I got my cranks from this guy. Service was excellent and so was the price.
http://www.ridemonkey.com/classified...0&ppuser=21995

[Keith B]

new XTR carbon/Ti rings are meant to last twice as long as a standard ring.

Easton just emailed me back to say the bars I crashed on met the same strength standards as their standard bars - despite the odd nick here and there :-)

[jcampbell]

I cracked my Easton Monkeylite Carbons in Mammoth... I am still buying another pair though.