Carbon fibre wheels.
 

Leading on from the "Aluminium Radials" thread on this board.

In the 1970's Citroen experimented with Carbon fibre wheels for their SM model.
Sadly little progress seems to have been made since then.

Does any one know of a source for these for road cars?

And why do F1 , Indy cars etc not use them?

Cheers , Pete.

My guess would be the heat generated by the brakes.

I read something on this awhile back... there are a few companies (at least one) overseas that make CF wheels, but they're not available for street use.

I *think* it has something to do with torsional loading, etc, that makes them more likely to decay and be damaged in short order vs. alloy wheels.

Even if you could get them, and get them imported, it's still illegal to run them on the street, as they're not D.O.T. Approved, and probably won't be any time soon. I'm sure there is a concern over the wheels being made of "fabric" or something.

This, of course, applies to US DOT, not Aussie. Have no idea about foreign (to me) countries.

I've been eyeing up a set of carbon fiber wheels:

http://www.zipp.com/_media/images/dy...ubular_set.jpg

http://spidermouse.us/images/smilies/wink3.gif

Do those have tires on them?

I saw somewhere... (might have been a joke) latex compound bike tires... very low weight rating, but they were supposedly LRR tires for bikes..

Most "carbon" bicycle wheels are only carbon fairings attached to an aluminum rim. The properties of the aluminum make it less likely to self destruct in a pot hole or something like that. After seeing a true carbon wheel colapse after a 5mph collision with a dog in the Tour de France there is no way I'd want one on my car.

As far as sturdy bicycle wheels I like American Classic's line of aero rims. The difference in aero is negligable for us mere mortals, the wheel is lighter, and costs a lot less.

Back in the 80's Carroll Shelby was building some great little hot rods based on fwd Chrysler platforms. The Shadow based 89 CSX had fiberglass reinforced plastic rims called fiberides. They were lighter than the alloy wheels but never really took off and to find a 89 model with those is EXTREMELY rare considering that they only made 500 of the Shelby CXTs. The wheels were fine for road use, but on road couses many of our Shelby/Dodge Auto Club members have found that the centers start to melt causing the lug holes to soften up and wallow out!

89 CSX-VNT Info

you remember the TV show "pacific blue" which had all kinds of bike cops? those were all spinergy carbon wheels. there is an al strip on each side but the rest is cf, spokes and all.

there are carbon wheels out there for cars, very rare, race only.
there are more options for carbon wheels for bikes and motorcycles

F1 & Indy race cars have many Carbon Fiber components but no CF wheels because
... given this characteristic of CF to delaminate (essentiall shatters into shards and dust, much like glass would) it is much too risky to use it for the wheels of an open wheeled race car capable of speeds in excess of 300km/h. Given the high potential for contact of all sorts in open wheel racing, I can’t imagine seeing a car traveling at those speeds and having it’s wheels delaminate from an impact and essentially turn into dust leaving only the rubber behind.

Carbon fiber is beyond EXPENSIVE. :eek: Up to $59 per yard.
Carbon Fiber/Graphite from Aircraft Spruce

The CF wheel in the attachment weighs 6.1 lbs. and cost $4000 per wheel. :mad:

fiberides
 

I attempted to locate a single wheel over the wrecking-lot parts-locater network for an Earth-Day exhibit and never scored.I understand that they weigh only about 8-pounds.Should one of your race friends want to part with one of the "ruined" wheels,I might purchase one for future exhibits.For street use they might have been okay,as they did receive DOT certification.From a mass standpoint they're quite remarkable!

Its to do with the tensile strength of carbon fiber and the low coefficient of thermal expansion

Wheels get hot they also get shock so you want a strong material that has a bit of give in it, carbon fiber is just too stiff to be reliable in the application of a wheel. When the wheel gets a heavy impact and the tensile strength is exceeded the wheel will explode rather than get bent like a normal alloy.

I think they do, since they're tubulars. Lightweight is good for climbing, but you get better momentum for flat course and downhill with a slightly heavier wheel, as long as the weight is at the rim and not the hub.

Saw a gimicky looking thing a while back that was basically weights on springs you attach to the wheels. At low speeds, the mass is near the hub for better acceleration. At higher speeds, the mass is closer to the rims for better momentum. Interesting concept and apparently, on the right course, can increase average speed.


But back to carbon fiber: carbon fiber failing is pretty high on the FAIL scale, far more so then the metal alloys.

This was also a concept that was used for a variable gearing system on bikes. I never personally saw one in use, but I saw them displayed at the local bike shop when I was a kid, and it didn't seem like too many people bought into it.

Faster you went, larger the rear sprocket would get... only in final gear though, and it had extra sets of teeth that would fill in the gaps to keep the sprocket "round" so the chain wouldn't leap.

I don't think they were that light or all the really fast Shelby/Dodges would scarf them up for use on their cars in place of the Borbets.

E-mail me your name, address, and phone number. I will put a feeler out on the two national forums and send your info ONLY to those that have rims available.

ataylorracing@comcast.net

:thumbup:

I meant the fast Shelby/Dodge drag racers, not road racers.

Thanks to all who posted.
There are some valuable points for further consideration there.

Pete.

The rarity of them, and relative difficulty to replace, might be a good reason they don't use them.

Hi,

The Britten V1000 had handmade carbon fiber everything -- the wheels were constructed in a "skin & bone" method, with carbon fiber:
http://static.panoramio.com/photos/original/5718288.jpg

The whole bike was just 138kg (305 pounds):
Britten Motorcycle Company

carbon fiber also isnt good with "shock" nor is it flexible.
i hear alot of the monocoque design cf bikes disintegrate after harsh use.

but i know they make carbon fiber sidewalled tires. not cheap stuff, and they only come in low pros i believe.

hear from whom?

i saw a guy repeatedly pick his cf bike up over his head and throw it to the ground in a fit of anger after flatting on a first lap escent and losing contact with the pelaton - the bike took it all in stride

awesome material

i ride with many people and unless it's a big crash, i've never heard of frames going

i have witnessed cf fork failures but that's a pretty demanding job


i have a set of these wheels, but have been too busy to try them out

http://www.pezcyclingnews.com/photos...no/toposet.jpg