When is a Tyre Not as Good as it Looks?

The quick read that will save you time and money!
What to look out for in your tyres and what to do to keep them in great shape.

As motorcycling becomes more and more leisure orientated, with many of us using bikes for recreational purposes rather than a daily commute as the case may have been in the past, it’s important to look at, and consider, the implications of the age of a tyre.

All tyres have a Tyre Identification Number or TIN number. This is also known as a DOT number in some markets and is pressed into the sidewall of the tyre during construction. It consists of a list of numbers. The last four are the ones we’re concerned with. They denote the week and year of manufacture. For example, a DOT or TIN number ending in 0511 tells us that the tyre was made in the fifth week of 2011.

Thanks to advanced methods and conditions employed by all the manufacturers – including Michelin, Bridgestone, Pirelli and Dunlop – in their distribution and storage systems, new tyres can be kept for years without degrading. This isn’t, however, the case once the tyres have been fitted to the rims of a bike.

Pressure points

There are a number of issues that affect the life and condition of all tyres, including motorcycle tyres. Just one of these would be how well the pressures (link to our blog on pressure when it goes live) were monitored and maintained. Even on a bike that was simply parked up and had its tyres go flat, the damage to the carcass and belt could render the tyre useless and/or dangerous.

Blowing Hot and Cold

Other than the radial structure failing, other factors that concern us include exposure to changes in temperature. The bike may have been run enthusiastically, allowing the tyres to come up to a wonderfully high operating temperature before being parked up and allowed to return to an ambient one, sometimes for a long period of time.

Sun Burn

Another factor that affects tyres is exposure to sunlight. UV rays are harmful to pretty much anything that is exposed to them, including all parts of a motorbike, and tyres are no exception. In this case they have a bleaching and drying effect on the tyres and the rubber will lose its pliability as a result of being over-exposed to the sun.

Wet and Wild

Moisture is also a factor in tyre degradation, with everything from mould to leaching to breaking the seal between the tyre and the rim being an issue. The steel belt in the tyre can become oxidised and unreliable as a result. The failure of the seal between the rubber and the wheel rim is the most likely culprit when it comes to the tyre degrading when in storage. Often overlooked is the tyre valve itself, which is more than capable of failing due to age.

So while your tyres are looking good at first glance, with decent tread depth, all may not be well. If other factors become obvious on closer inspection, such as a loss of flexibility in the rubber itself, a lack of lustre in the tyres, a network of cracks on the side walls and in the crown and shoulder of the tyre which appear within the threads, it may be time to ask someone who knows a little more than you to take a look at them. Ride to us at Essendon Motorcycles & Mowers any time to get your tyres checked for free.

Aged tyres simply don’t perform as well as new ones. One of the big benefits of putting on a new set of rubber is that the industry is updating their products all the time and continuing to provide a huge choice of sizes, including ones that will help your classic to handle with a little less character and a lot more predictability.

Going back to the TIN or DOT number, if your tyres are more than five years old then it really is time, in the interests of safety and performance, to have them replaced. If nothing else, you’ll be reaping the benefits of all the positive changes in tyre construction over the last half decade.

Want to find out more? Check out our blog, and download our Essential Guide to Choosing the Right Tyres and How to Maintain Them

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To find out more about Essendon Motorcycles & Mowers and our services please contact us directly on (03) 9351 0055 or visit our website!