I’m sure there’s a perfectly rational, scientific explanation for this. Or, alternately (in the case of car tires) perhaps a law that prohibits it. That said, I’ve been unable to find any.
Why DON’T tire manufacturers produce different colored tires? Seems like you can customize every other part of a car.
This might help: http://www.omg-facts.com/view/Facts/40939
Tyres are black because carbon black is a cheap additive that greatly increases their strength and lifespan.
when I was a kid I had a BMX-style bicycle with blue tires, so it’s not unheard of. As I understand the physics, though, the carbon black (soot) which gives tires their black color is there to improve abrasion resistance. Assuming that, a non-black tire might wear out a lot faster in the absence of other abrasion-resisant compounds.
there was a manufacturer a few years back that offered tires with colors, but it was only a narrow circumferential strip or two in the tread. I’ll see if I can find a link.
ETA: found it, the BF Goodrich “Scorcher”
looks like it was a really sticky racing/high performance tire, so tread life wasn’t so big a concern.
There are colored bicycle tires.
I would imagine that car tires would be very difficult to keep clean.
Bicycle tires are offered in several colors. The colored tires are typically inferior in at least two figures of merit: Wear, Traction, resistance to weather checking (dry rot), wet traction, rolling resistance.
I think it is possible to color a tire. The problem arises in the fact that any rubber product in contact with asphalt is going to turn an ugly shade of black, so that beautiful red, blue, whatever is soon going to be dingy gray/black in color. I can’t see a tire maker out there that would want to be assosiated with a product that looks like hell shortly after you use it.
It is interesting that rubber wire insulation comes in many colors. I failed to take advantage of working for a wire company to check the specifications for different colors or see if their formulation was different. Perhaps if you don’t use any carbon black, you have to go easy with the other fillers such as calcium carbonate and clay.
I do know the toughest cable of all, mining cable was usually made in bright orange or yellow for visibility in the mine. You don’t want accidently cut an extension cord in a damp location carrying 480 volts on conductors the size of your thumb. Mining is highly mechanized and the equipment is all electrical underground. Much of the surface equipment too.
So I would think you could make good tires out of the same stuff.
I think I have seen hype on coming colored tires now and then. Maybe obbn is right about the appearance.
I may well be wrong, but I suspect that the rubber on automotive or truck tires needs to be far more tough and durable than the rubber coating on any sort of electrical cable – even that used in mining.
All car tires need to have some carbon black so that they can meet a minimum conductivity. Even silica filled tires, which would be a light grey color if all silica, have a few percent carbon black added.
There have been a few attempts to produce different colored tires, but they all are just a laminated layer on the sidewall of the tire. This is also how whitewalls are made. This is an added cost to the tire, though, and can also compromise the sidewall strength since the rubber is no longer filled.
You can also get tires that leave colored marks on the pavement or colored smoke when you burnout.
I highly doubt that even tough mining cable is used the way that tires are regularly used, considering the abrasion on the road plus added friction from the brakes, while keeping a certain pressure inside and being exposed to heat and cold, contraction and expansion.
A wire insulation just stays around the wire. The temp. inside a housewall or a mine will fluctuate far less than for an outside tire. There’s no pressure from air inside. There’s no abrasion, since cables don’t move.
In addition, coloured cables are sometimes prescribed (for electrical wires) or make sense (in mining), so the companies don’t mind the small difference; whereas car and bike tires are bought by end-consumers, who mind a cost difference very much.
IIRC the most common wire insulations today are vinyl (PVC) and teflon. I don’t think rubber is used much anymore except for the “jackets” over multi-conductor cables.
I have a blue bicycle tyre that is designed just for turbo-trainer use and it says ‘not for outdoor use’ on the sidewall. I’m guessing it’s a hard compound to stand up to the turbo-trainer and would have rubbish traction outdoors.
Guess a few of you know little of mining cable and conditions in mines. The cables are continously being drug over rocks in all kinds of weather outside. It gets quite hot in underground mines.
When you look at what some people spend dressing up their trucks, I am sure you could charge a premium for them.
What were “whitewall” tires? I have vague childhood memories of them being something that made a car special. Did they have other colors available besides white?
Red, but it usually wasn’t as thick as a white stripe was.
Carbon black also provides a cheap and readily available form of UV resistance. Without it, your tires would crack. You can formulate rubber with UV-resistant components but they would be more expensive. I would bet that you can get colored car tires, but it would not be as cheap as the mass-produced tires with carbon black.
You can have certain types rubber made with just about any Pantone color you want.
Tires are usually blends of natural, SBR, and EPDM compounds because of their properties. The bushings in your car are almost always natural rubber. The weatherstrip on your car is usually EPDM or a thermoplastic EPDM formulation, Sarlink or Santoprene.
The equipment we make for the mining industry has to be MSHA approved. We use neoprene compounds to get MSHA approval (not that other material cannot get approved) because it is self-extinguishing. I would suspect a lot of parts for the mining industry use neoprene.
The new Corvette headlamp gaskets are Neoprene. The H2 headlamp bezel closeout is neoprene.
Whitewalls (now) are just a layer of colored rubber added to the tire carcass during its construction. At one time, tires were made of just natural rubber, colored white. Natural rubber tires disintegrated a lot faster than current blends. Carbon black slows the disintegration.
[Danny Torrance]Redwall … redwall![/DT]
I just watched a commercial for Yokohama tires made with orange peels. The tires were, very disappointingly, not orange.
Whitewall tires. Very popular in the 50s and 60s.
http://static.howstuffworks.com/gif/1957-corvette-7.jpg
Redline tires. Popular, especially on muscle cars, in the 60s.
The original Hot Wheels diecast cars had redline wheels, mimicking this look:
http://www.cash4redlines.com/CudaRedline.jpg