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More carbon fiber please!
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Wonder how they work. Drag race is pretty much an aluminum-only world and NASCAR uses steel wheels. I know some drag classes require certifications for them. But, I've used a carbon fiber helmet for some time, and also the scoop for my dragster is carbon fiber. I've also seen carbon fiber valve covers, and composite intake manifolds.
 

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Don't be hasty.
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Motorcycles have used carbon wheels for a little while now. Definitely a race only idea for cars though, not too friendly with rocks and curb scrapes I'm sure. 6 lbs for a 18" ish wheel is pretty amazing though.
 

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Seeeriously easy Livin
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thats pretty nuts. I don't now how much of that can be tranfered over to bikes though. Carbon rims are definitly going to become more common, but I don't think full carbon spynergy style wheels will ever be able to compete with the rim and spoke arangment.
 

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Motorcycle racing...

such carbon wheels already got used in Motorcycle Grand Prix Racing. I remember Max Biaggi used such wheels on his 250cc Aprilia about 10 years ago...now i'm not sure if they banned them because they wanted to protect the privateer Teams. Only factories could afford such wheels and replace at regular intervals;)
 

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More carbon fiber please!
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ginsu2k said:
Bad bad bad....imagine the temperature your brakes get after racing. And remember that the resin in carbon burns off at about 400degF !
Many drag race cars use a carbon composite rotor. The hotter they get the better they perform. It's all in the proper intended use and construction of the products. Carbon and other composites have their place when properly engineered.
 

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Formula 1...

ginsu2k said:
Bad bad bad....imagine the temperature your brakes get after racing. And remember that the resin in carbon burns off at about 400degF !
well - you obviously are no into motorsports: in Formula 1 there's ONLY carbon rotors! They need several hundred degrees to actually perfrom!

Same for MotoGp brakes where guys like Valentino Rossi etc. use carbon rotors. only when it rains those guys use steel.
 

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Big diff between C-C composites and C-F composites.

Thanks for mentioning that Soya. Now lets start the lesson:

Let's start with talking about the 'weakest link' which is the matrix material which most people know as 'resin'.

Composites are a combination of fiber reinforcement and a resin matrix. The resin system holds everything together, and transfers mechanical loads through the fibers to the rest of the structure. In addition to binding the composite structure together, it protects from impact, abrasion, corrosion, other environmental factors and rough handling. Resin systems come in a variety of chemical families, each designed and designated to serve industries providing certain advantages like economic, structural performance, resistance to various factors, legislation compliance, etc. Only the most common resins of the thermoset family and the ones mostly used in composite construction are described below. Those are Polyester (orthophthalic and isophthalic), vinyl ester, epoxy, and phenolic.
Advanced composites possess enhanced stiffness and lower density compared to fiber-glass and conventional monolithic materials. While composite strength is primarily a function of the reinforcement, the ability of the matrix to support the fibers or particles and to transfer load to the reinforcement is equally important. Also, the matrix frequently dictates service conditions, for example, the upper temperature limit of the composite.
Now, the upper temperature limits for an epoxy resin are around 400degF, so that defines the limit at which the material can be continuously operated at. If you watch Formula 1 a lot you will notice that near the exhaust section of the vehicle all the carbon-fiber components are liberally decorated with stickers that record the maximum temperature (they turn color in the heat). This is so the engineers can know if any part was operated near it's maximum temperature so that it can be replaced before the next race or test.

Now, the Carbon-Carbon composites as used in F1 brake discs and the nose of the Space Shuttle is an entirely different type of composite that has much higher manufacturing costs associated with it. You can also tell visually the difference in C-C composites and CF composites because you can see the fibers in CF whereas in C-C it's mostly a dull black.

Carbon-carbon composites consist of highly-ordered graphite fibers embedded in a carbon matrix. C-C composites are made by gradually building up a carbon matrix on a fiber preform through a series of impregnation and pyrolysis steps or chemical vapor deposition. C-C composites tend to be stiffer, stronger and lighter than steel or other metals. It was developed for the nose cones of intercontinental ballistic missiles, and one of its most widely known as the material for the nose cone and leading edges of the Space Shuttle. The Brabham team pioneered its use in the brake systems of Formula One racing cars in 1976; carbon-carbon brake discs and pads are now a standard component of Formula One brake systems.
BTW, I found a link to one of those carbon-carbon brake rotors for motorcycles, currently selling at $1000 a piece!

And, of course, the required graph comparing different materials: Tensile strength vs Temperature. Please note the slope of the line drawn for Epoxy/Uni-Directional Carbon Fiber Composite That means the material with the highest strength went to the lowest in about 100deg C! Pretty scary!!
 

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