Tires - Dull or Dynamic? Part two

Following is the second part of an article I was asked to write for a tire industry trade publication in the UK. “Tyres International.” I thought you might find it a bit interesting.

“To the untrained eye it might seem like the tire industry has not done much to improve John Dunlop's original. But looks can be deceiving.

Part two
A cost/performance comparison on the improvements in wet and snow traction, ride comfort, low noise, blowout resistance and handling response is significantly more difficult, as the tire of 1920 was so poor in many of these areas as to be considered useless when compared to today's tire.

When one considers high-speed capability it is a little easier. In 1920 most cars were not capable of a sustained 85mph, yet today that is considered an absolute minimum high speed capability for a tire to be sold for use on the public highway.

Material World
Some would have us believe that today's tire engineer is not willing or even encouraged to look at new ideas or materials. Even the use of rubber, both natural and synthetic is used as an example of the perceived lack of advancement in tire technology.

I know from personal experience that alternate materials for both wheels and tires have been investigated but either lack of performance or poor reception in the market prevented those ideas from making it into production. I have seen non-metallic wheels that were too flexible to hold air at high temperatures and too stiff so they shattered at low temperatures. New tire sizes with improvements in safety and mobility were not accepted because non- standard wheels were required. Even well engineered items such as the mini-spare, still meet with resistance and ridicule despite the fact that they can deliver acceptable performance when needed. They even have an impact on vehicle fuel economy when not needed

Rubber band
The basic material in Mr. Dunlop's tire, natural rubber, comprises less than 10 per cent of today's modem passenger radial. Today's tire, with 25-30 different materials, made up of hundreds of different chemicals, is one of the more complex components in a modem automobile. This is especially surprising when you consider that some materials are considered contaminants and are incompatible with other materials in a tire yet we have managed to make these incompatible materials work together to deliver improved air retention and blow- out resistance.

It is likely the concept that tire materials have not changed is a concept only held by those with little training in the an of tire design. There are few materials that are capable of 300 per cent strain for tens of millions of cycles over an operating range of temperatures from -20°F to +200°F while at the same time having a coefficient of friction of 0.8 or higher. Today's steel belted radial could be improved upon and even have its weight lowered, with increased use of rayon, fiberglass or other materials as belt material. There are however, restrictions on pollution or customer resistance to materials other than steel which have so far proven insurmountable obstacles to broad appeal for the average consumer.

Some of our biggest challenges will come in the next decade as we are asked to change from making a product that will last indefinitely under extreme conditions as the tire industry has been asked to do for more than a hundred years. We are now being asked to design a product that will be almost indestructible until the user wants to change it, then the tire should, as if by magic, become easy and inexpensive to deconstruct into its chemical components. Some OEMs are even starting to suggest that old tires should be able to be recycled into new tires with no loss in any performance characteristic.

I have every confidence that the tire industry will rise to this new challenge and methods will be developed to address the disposal and reuse of materials in a tire. It is unlikely the recycled materials will be used 100 per cent in another tire just as the OEM will not be able to recycle the leather car seat into a good as new' leather car seat, but we will incorporate an ever increasing percentage of recycled materials in tires and we will find acceptable methods of recycling them into some usable material or product at the end of their useful life as a normal tire.

To the uninitiated it is easy to look at John Dunlop's tire of the late 1800s and say that since today's tire is still made of "rubber' it is not really any different. Thus some would consider this sufficient proof to postulate the tire industry is not capable of looking at history, learning from it and moving on.

It is my belief that this thinking ignores the advancements in both the materials and performance delivered at a very low cost to the often uncaring consumer.