Words and Photography by Bryan Grant
Header photo by Robb Cox
Diagrams courtesy of Bridgestone Australia

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DRIVING STYLE

The way you pilot your vehicle has a huge impact on tyre wear as the rate of wear versus external influences (speed, braking and load) are directly related. As such, it pays to play it smooth.

The faster a tyre turns, the quicker it wears. A tyre that is driven at 70km/h will have a life expectancy 20-percent lower than the same tyre driven at 60km/h.

Obviously, we can't always drive under 70km/h but minimising excess road speed not only prevents being caught on camera, it also promotes longer tyre life. Avoiding excess acceleration and using smooth throttle application will save you big bucks on fuel to boot.

Time to stop! Braking forces also impact tyre life significantly. In this example, braking heavily from 55km/h causes more than double the wear than braking from 40km/h!

An increase on the load (weight) placed on the tyre causes a similar result to underinflation. Based on the factory load rating of a tyre, increasing the load by a mere 20 percent will reduce the tyre’s service life by 30 percent. If you intend on carrying a heavy load, it pays to increase your pressures to suit. Again, this is where the Tyre and Rim – Standards Manual comes in handy.

OLD TYRES = DANGER!

One hazard that is often overlooked is the age of your spare tyre. Tyres 10 years or older are an accident waiting to be fitted. The bond between the rubber and steel/fabric belting weakens over time, and the rubber itself becomes hard and brittle.

Phil Burnard from Bridgestone says that all too often he sees the effects of using an old spare tyre (the image you see here was from a 15-year-old tyre that had lots of tread and ‘looked ok’ to the owner), and they can be potentially lethal.

If you’re unsure of the age of your spare tyre, either see your local tyre dealer to get the best advice, or check out the following.

Locate the ‘Dot Code’ on the sidewall of your tyre, which should resemble something similar to LH9L JCB 0901 (example only). The last two digits of the code are the tyre’s year of manufacture. In the example, this is 2001.

The old theory of putting tyres away in a dark shed for a few years to make them last longer is not good advice at all.

The old rubber may take longer to wear, but the hardened compound means a big reduction in the tyre’s grip levels and hence your family’s safety.

Tyres are treated with conditioners to ensure peak performance and should be used as soon as they are purchased.

LOW PRESSURE = HIDDEN DANGER!

Low tyre pressures are often used for off-roading in sand and mud. However, this practice is potentially disastrous for your tyres, and for the first time I’m not talking about the tread.

When a tyre runs at a pressure too low, it causes flex in the sidewall in a concentrated zone. This flexing action causes friction in the various materials of the sidewall and creates a band of excess heat along this point.

The heat build-up can quickly deteriorate the rubber in the sidewall and cause it to blister. The tyre literally starts to destroy itself from the inside out while there is very little visual evidence of this. This action compounds as speed increases.

This is very important for those of us who frequently run low pressures, then travel on the road (bitumen or dirt) to another track. Personally, I had always just thought that it promotes more tread wear, not knowing about this tyre-destroying factor.

Avoiding speeds of more than 30-40km/h and airing up for extended travel periods will minimise tyre damage

Thanks

Thanks to Bridgestone Australia for supplying the diagrams used in this story.

» Visit Bridgestone Tyres Australia