Carbon Steerer Tubes
 

Do you trust em? Can you back it up?

I'm trying to spec out my new bike, and I'm if getting a fork with a carbon steerer tube will be an issue.

I've never had a failure, but my carbon fork with alloy steerer tube gives me the creeps. I don't know why.

no. and no.

How many times are we going to have to say this.

NO HE DIDN'T...that steerer was ALLOY, not Carbon.

"The last crash apparently a result of the first incident happened when his aluminum steer tube broke at the intersection with the stem."

Dude... read the article before you post the pic... get your sh*t straight.

Hincapie's steerer was Al, and he crashed it earlier.

As to the original point, dunno. Sheldon says he doesn't recommend them, and, other thing being equal, I'd pick an Al steerer to save a few bucks and have more peace of mind.

Aluminum steerers can actually be a lighter system than carbon steerers since you don't have to use a bulky reinfoorcing plug in them. The all carbon fork may be lighter, but factor in that special plug and the aluminum steerer with convention starnut can come out ahead.

I was hoping that picture wouldn't make its way over here...
Let me give the Tivo version...
Pix of broken bike.
Smug anti carbon zealots point fingers
Carbon zealots spin doctor the pix
Trek jumps in and starts their own spin...including flaming every other carbon manufacturers (aka offshore)
Eventual conclusion...pro riders kick the snot out of their bikes

<cue the carbon vs alloy vs everything else flamewar>

i rode a full carbon fork (in addition to the carbon post, bars, and other stuff) on my road bike for 3 or 4 years with absolutely zero problems. rode it all over rough nyc streets, rain, snow, thousands of training miles, group rides, racing, the occasional minor crash, and never a problem.

i'd use a carbon fork without a second thought.

It's funny how anti-carbon people are, without realizing there's a reason why everyone uses it: strength. You think track racers give two shts about weight in comparison to other factors? No, it's strength, and stiffness that matter. It just so happens that you can achieve many times the strength of other materials for a fraction of the weight, without rider weight limits like in Ti.

As for "catastrophic failure," you do realize aluminum only bends once, right? Then it snaps? And that the joint between aluminum and carbon is going to be weaker than a solid piece of carbon? If water enters the carbon matrix and the carbon isn't properly insulated (fiberglass), you'll get some nasty galvanic corrosion (hell, without insulation you'll get it without the water).

If you can afford it, go for the cabron steerer tube. You'll have to be a little more careful with putting on the stem, but if you're not a ******, it'll give you a stiffer, yet more shock-absorbing ride.

what he ^ says.

*if* you get one, after you tighten the stem, don't twist it or anything. if you didn't get the stem on square first time, loosen everything fully and try again. otherwise you risk scoring the carbon, which then would be where it would crack.

also make sure you have a torque wrench. carbon doesn't like over-torqued bolts.

fsnl
sparky

how do you cut the tube to length? Do you have to seal it?

you cut it with a hacksaw. i've never heard anything about sealing it.

Hacksaw with a special blade, mind you. Depends on the manufacturer but high tooth count or ceramic blades are the norm. Always read the installation instructions or take it to a shop.

Awesome, I'm gonna go for the carbon steerer, and I'm going to have my LBS cut it for me. Thanks for all the help!

I guess they will know that there is a limit to the spacers combined height for most (all I know) forks with carbon steerers - check the instructions or, if you need more spacers, use something like Serotta insert, press fit between the headtube and the top race of the headset.

^ yeah. it tends to be somewhere around 25mm

The steerer is a different story. Everyone agrees that carbon doesn't really like things being clamped onto it. If you overtighten, it can and will crack the carbon. I guess its surface is not as hard as metal anyway, so the edge ot the clamp could damage the carbon if it has burrs, or you crash etc.

They also don't give two ****s about long term durability.

ALso, no star nut, just a compression plug which gives the stem an internal "backing" to prevent deformation.

Obviously, threadless only. I just installed my new spez. carbon pro fork w/carbon steerer. Dropped more than 1/4 a lb with the fork alone switching from a reynolds comp.

Torque wrenches are your friend. Besides, carbon handlebars (which are clamped onto the stem) have been used on mountain bikes for years, where they're exposed to arguably more torque, far more vibration, and greater impacts as well. If it's installed correctly, you probably don't have anything to worry about.