I read the Velonews "review" and there are all sorts of comments floating about concerning the bead area. Does anyone have any actual experience? I like my Al/Carbon rimmed clincher wheels, but of course I'm always after ways to save weight, and this might be one (rims on the wheels I have are 502 and 506gm). Before anyone tells me to go tubular, I already have some full carbon tubulars, but there are days when it's better to be riding the clinchers.

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Ride lightly!

Experence: I have seen 2 Corima HP rims fractured by tight tyres and narrow tyre levers.

Losser tyres and Michelin type tyre levers didn't seem to cause these problems, but everyone roud here went off them pretty quickly.

The Ryenolds carbon clinchers look to be designed with this in mind, but I havn't put any into the shop - yet.

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Success is how far you you bounce back up after being knocked down

I think Campagnolo have the most advanced carbon clincher design - Their Hyperon C rim is beautfiul; not to mention the carbon layering.

we did a lot of testing to try and produce a carbon clincher at nimble. found that it took so much carbon to hold the bead that it was not worth it. aluminum was much lighter in this application. so some have produced em since but i think they are all still pretty vulnerable if narrow and light.

here is an example of their alu bead on carbon.

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Eventually someone will figure out how to make a radial fiber layup in the bead/brake surface area only, so that the carbon fibers are oriented exactly parallel to the bending stress induced by the pressure in the clincher tire pushing out on the bead seat.

we did all that, made it work well but the minimum to keep it from blowing out was heavier than the aluminum option.

it really isnt rocket science, just a matter of application. carbon isnt for everything

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That's amazing considering how much stronger the fibers are especially when you orient them parallel to the direction of the load. I suppose though that since it's a bending load in the braking surface/bead seat that the stress and deflection is going to be more dependant on the thickness squared rather than just the strength of the fibers in pure tension. Maybe if one could make a small sandwich structure of one radial layer of carbon fiber, about 0.050" thick layer of foam and another layer of carbon fiber for the rim brake surface. One could have the strength and moment of inertia benefits of the carbon fiber on the outer surfaces where you need it and the light weight. Kind of like a thin version of a honeycomb sandwich panel. Just a thought.

I've asked about it before...but what about the multi-directional stuff similar to the Campy crank material?

It's what Reynolds is using in thier Stratus Clincher, the only carbon clincher I would trust. Rated up to 165 PSI. Reynolds knows thier stuff, and they are a company that would never sell a bad or dangerous product.

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Are the Stratus Clinchers any good?

I love my Reynolds clinchers --- I have the 2004 model with the new Reynolds hubs, bladed spokes -- fast, great feel, very stiff both laterally and for power transmission. Braking is right up there with my Lightweights............

Those Reynolds have been on my wish list for a while. I'm still hesitant however and I'm not so happy about the weight.

Are the Stratus Clinchers any good?[/quote]

Health Net is using them. From what I've heard they really like them.

I think if CarbonSports want to "step it up" just that extra bit more than what they already have...

They should design the "Lightweight Carbon Clincher".

Imagine...

Here is a (bad) picture of a carbon clincher rim after the brake track melted during use! It folded outwards from the tire pressure.

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Ride lightly!