scarlson 

I was given a pair of scruffy and scuffed-up looking carbon fiber wheels. I want to know what this crowd thinks about riding on them.

They are Vision brand, seem to be from the '90s or early '00s. They take tubulars, which are a technology/art that I've stayed away from so far. Right now they're set up as wheelchair wheels, with stub axles, for a high-performance wheelchair application (the guy who gave me them says they were used by a disabled man to compete in the Boston marathon some years back) but they were originally bike wheels. Both are rears and they take English threaded freewheels. I would never use any carbon wheel on the front, but It would be very little trouble for me to turn them back into rear bike wheels by putting in some ordinary axles.

The question is, are they in any condition to ride on?

Here are some pictures of the worst of the dings. I think the dings were caused by the temporary installation of a clamped-on hand-grab-ring so that the wheelchair rider could push.

I have an idea of which way this is going to go, but I'll withhold my judgment until I get a reply or two. I also genuinely want opinions, because I have no idea myself when it comes to carbon fiber.

bikingshearer 

I wouldn't ride 'em. Of course, I wouldn't ride any CF wheels because I'm a luddite. But if I wasn't such a luddite I certainly would not trust a wheel that was (1) CF that is (2) old and (3) is that used ad (4) is that scuffed and (5) is that load-bearing.

notenoughdaylig 

Toast

USAZorro

I know just a smidge above nada when it comes to carbon, but my general policy is, "if catastrophic failure seems an option, hell no" applies here. Maybe you can put these on a trainer for a while to gain confidence, but sale on e-Bay under "vintage cycling wall art" would be likely if I were in your shoes.

gugie 

Č importante ricordare, che cosa potrebbe andare storto

Wildwood

gugie 

Bene!

squirtdad

heck with whether the will kill you or not....they're ugly....ditch them

scarlson 

You guys have made my night!! I had been agonizing over it and I appreciate the clarity and humor.

Had to use gargle translate to get the Italian scoop on things. And yeah, I've visited the busted carbon blogger.

I like the idea of riding them on some rollers, but I feel like this would not accurately simulate the stresses of the real world. Also I agree they are ugly! Or at least a bit "chalk-and-cheese" with my aesthetic, as the British would say.

I'll throw them on Ebay, I guess. Or save them for when I need to take out some frustration on an inanimate object.

Cheers everyone!

homelessjoe

those would be fine to ride around the block or run up to the corner store on.......but they are really rough.....I would not call those reliable wheels at all.....you can get really racked in a high speed bike crash.......new carbon is super strong and reliable ....old carbon is not..........those super bikes they use in pro racing and on the tours .....are x rayed every day..........some bikes and wheels get retired after one day..........some teams take over 100 bikes to the races now........you can trust in carbon but bring an extra bike

eja_ bottecchia

Si...

bikingshearer 

Think nothing of it. In your heart of hearts, you knew the answer. We just confirmed it. And by doing so, we freed you up to go buy something else. We love egging each other on to go buy something else.

iab

I'm certainly happy crabon myths are still being perpetuated today. I was worried actual facts would be used in this thread.

nlerner

Carbon haters are entitled to their own facts.

scarlson 

What does mean? If you have a dissenting opinion, I'd love to hear it.

iab

I have a set of carbon wheels. I'd sit on the rims unlaced without fear of collapse. They are by far stronger than any flimsy aluminum rim I have ever owned.

And while I am not a structural engineer, I don't know for certain unlike others, that the damage on your wheels is structural. Put it on the trainer, see what happens. Ride it around the block, see what happens.

I worry more about a tacoed aluminum wheel than a assploding crabon wheel.

abshipp 

I see an aluminum brake track. Any chance that this is carbon built around an aluminum rim?

If that's the case, I would make sure that the bond is in good shape around the carbon/aluminum interface. That damage looks like it's not on the spokes, so I personally wouldn't worry about it too much.

Of course, this is just my opinion based on a few photographs. YMMV

Oh yeah, what he said ​​​​​​​

Chombi1 

I would think, any cracks, scrapes and gouges that are deep enough to expose the carbon weave below the finish, is a good enough reason to "red tag" a CF wheelset like that.

DMC707

id have no issues riding them. Specialized made these too. The front wheel in my pic also is threaded ,it just has a rubber cover protecting the threads, but the axle length isfront specific

Bonded aluminum rim. This particular wheel has been used hard and still has no issuesthat i can tell


buuuuut. —-if you are not comfortable with them - totally understood. You wont hurt the wheel’s feelings

scarlson 

Yep, it appears to be carbon bonded to aluminum hub and rim. I will check the bond area for further damage.

It actually is. All the pictures of damage are of damage on the leading or trailing edges of the spokes, close to the outer ends where they join the rim. I think the guy that used them on a wheelchair had some grab-rings attached with clamps to the spokes, and I surmise they caused most of the damage I have pictured.

I don't really have a bike that "goes" with them, so I may put them up for sale for an attractive price someplace, with full disclosure of course. Anything I make is profit since they were given to me.

repechage

I would get an assessment from a carbon fiber repair facility.
Carbon can be repaired. it will most likely require them to be balanced after.
Is the cost worth it? no idea.
I would also assume that afterward they will need paint, or as part of the process.

the latest and greatest in carbon damage assessment is infrared
granted, this is for sailboat hulls and appendages, but the tech is similar

https://ericgreeneassociates.com/imag...Assessment.pdf

abshipp 

Ah. I think that changes things a bit. I thought those clamp marks were on the rim between the spokes.

dddd

The mass of the rider is always a big consideration in guessing how over-built that a component was originally. Us featherweights get away with all kinds of things, up to and including old tires (inflated proportionally to actual loading).

Carbon wheels tend to be quite strong structurally, from what I've seen, but I myself would likely only use a matched set of this style of wheel (that's just me).

Catnap

I'm with IAB. those wheels are fine to ride, dunno what all the hand-wringing is for. there's so much carbon used in a tri-spoke like that, it's nearly impossible to have a catastrophic failure.

scarlson 

After a closer look, the answer seems clearer.

Even without the axles, they weigh 800g. Not horrible, but not great either. You can fairly easily build a clincher wheel of metal that weighs less than this. A tubular wheel, extremely easily! And on top of that, they take freewheels which are often, but not always, heavier than cassettes!

So, for me, it's not really worth it.

Also, inspected them in better light and found this. You can stick a penny in that crack. I'm sorry but No Thank You.


Does anybody want them for the cost of shipping? To use on something that's Not A Bicycle? Happy to include the axles or I could remove them if you're planning on running quick releases and attaching them to a normal bike. Could also put them on a trailer or cart with the stub axles they have now. There are literally thousands of uses!