Our Tyres 101 will help you better understand your tyres and how to look after them. Tyres are the critical link between our cars and the road. No matter what your cars EURO NCAP rating is, or how many airbags your car has, if it can’t stay stuck to the road, you’re in trouble.

In our experience, it isn’t that people don’t want to look after their tyres – it’s just that you don’t know how to look after your tyres! Mumbo-jumbo like balancing a tyre, rotating tyres, tread, walls and the like is just way too complicating. Nevermind the secret codes written on them!

Never fear – Carter is here to help!

There are a couple of important basics that will get you on your way. Here are the three key areas of tyre basics:

  • Tyre 101 – understanding what makes up a tyre
  • Tyre care – how to proactively keep your tyres in good working order
  • Tyre damage – what to watch out for


Tyres come is all shapes and sizes – as well as different rubber composition. Each car is designed to be used with a particular type of tyre. Check your User Manual as well as the side of your driver’s car door to get the standard tyre information for your car.

The information on your tyre tells you a couple of things:

  • The manufacturer (Goodyear, Khumo, Continental, etc)
  • The tyres measurements (diameter, width and wall thickness (the measurement from the
  • The tyre hardness (how hard or soft the rubber is)
  • Modern tyres now also include treadwear, traction and temperature ratings above the basic tyre measurements

Let’s take a look at why these factors are important

The Manufacturer

Getting tyres from a reputable manufacturer is important. This will ensure that the quality of the tyres, the specifications and performance characteristics can be trusted and are in line with international manufacturing and performance standards.

The Measurements

The three big numbers on the tyre represent:

  1. The width of the tyre in millimetres: In the image above from Goodyear, the first number is 215 – indicating that the tyre is 215mm wide, from sidewall to sidewall
  2. The aspect ratio of the tyre in %: this is the cross sectional height of the tyre (pretty much from wheel rim to edge of the rubber) compared to the width. In this case the cross sectional height is 60% of the width
  3. The rim diameter in inches


Tyre numbers


Why are these important?

The wider the tyre, the more contact you will have with the road. That is why big Jeeps and Hummers have really wide wheels (you can see it clearly when driving behind them). This gives them more grip. Obviously, the wider the tyre, the more expensive the tyre as it takes more rubber to make it bigger.

The cross sectional height protects the rim from bumps and sharp edges in the road (such as the edge of a pothole). While a “low profile” tyre with very low cross sectional height may look cool, you can very easily dent your rims. Damaged rims not only look bad but are also a safety issue as cracks can form or it may not secure your tyres properly. A low profile tyre is stiffer and offers good performance in handling and cornering. Great on Kylami Race Track. Not so great navigating potholes on William Nicol…

Rim diameter improves ride quality. Think about the little wheels on a toddlers plastic push bike. Ride that over rough paving and the vibrations could chip your teeth. Now ride a mountain bike with 29 inch wheels over it and you barely feel the roughness. Same principle, just applied to cars. You’ll feel fewer of the roads bumps and corrugations with larger wheels – that’s why SUV’s meant for dirt roads have large diameters to improve ride quality on rough terrain.

Obviously, your car is made to run with a particular type of tyre. You cant buy Hummer tyres and put them on a Smart car. Check the user manual and ensure you buy the correct tyres.

Tyre Hardness

Many debates have been had over tyre hardness. The basic principle is this: the harder the tyre the longer it will last. The softer the tyre, the more grip you will get on the road. The balance is to have tyres that last but grip the road sufficiently.

This is more of a trade off and issue with SUVs. Gravel roads are really tough on a tyre. Soft tyres will really be put through their paces and not last long. So, buy hard tyres. BUT, you generally drive on highways and tarred roads before you hit the gravel – so buy soft tyres for road safety. See? Tough trade off.

A hard tyre on-road would have less grip when stopping and cornering.

The helpful measurements on a tyre are:

  • the speed rating (generally a letter from Q to V – indicating max speeds from 160km/h to 240 km/h)
  • Treadware, traction and temperature are relative measures for the softness / lifespan of your tyres Check manufacturers websites to understand how various options for your car will perform on and off road



Safe, defensive and calm driving will go a long way to increasing your tyres lifespan. All wheel drive or four wheel drive vehicles often experience longer tyre lifespans due to the traction control systems on these vehicles which distributes power evenly across all wheels. There are a couple of proactive things you can do to get more out of your tyres:

Keep your tyres correctly aligned and balanced

Tyres that aren’t running true can experience uneven and / or excessive wear. Making sure your tyres are correctly aligned and balanced will ensure this is mitigated. Balance and align your tyres more regularly if you hit a pothole or bump; take your vehicle offroad or bump into a pavement.

Rotate your tyres

Your front and back tyres experience different loads and forces – especially in front or rear-wheel drive vehicles. This means uneven wear. Rotating your tyres (swopping the left back with right front; and front right with left back) will result in more even wear of your tyres.

We would recommend having your tyres rotated, balanced and aligned annually. Ask if your dealership can do it as part of your annual or kilometre based service. The cost is minimal and the benefits significant.



Tyre bubble damage side wall



Roads are full of stones, nails, glass and other debris that can damage your tyres. Impact with bumps and edges can cause wall damage. As you were taught in your drivers’ license lessons, regularly inspecting your car and each tyre is important. We would highly recommend having any suspected damage to your tyres inspected by a reputable tyre dealer or your car dealership. Don’t wait until you have a flat! A blowout at 120km/h can be extremely dangerous to you and other motorists.

Damage such as nails and screws can often be repaired with a plug. Wall damage, however, is serious and you should promptly replace the tyre. See image below of a typical wall damage “bubble” that you should look out for.

There you have it, tyre no more! As we said, your tyres are the critical link between all your fancy gadgets and passengers and the road. If you are unsure of anything or suspect any damage to your tyres, consult trusted professionals so you can keep yourself, your family and other motorists as safe and sound as possible.



***Disclaimer: This is the Carter blog-space. This is not a peer-reviewed scientific journal. These are not the thoughts, views or opinions of our business partners, or anyone important for that matter. None of this content is sponsored. We are not technical experts in any of the areas presented. We are just a bunch of people who like to gather information that we believe may be helpful to you.

Do your homework. Find experts. Research. We are just here to provide some thought starters to chew on. Judge us. Tell us we are nuts when you feel we are. Tell us we are helpful when we aren’t nuts. Where scientific studies can be quoted, we will quote them – otherwise it’s laymen-central around here.

Carter makes no representations as to accuracy, completeness, currentness, suitability, or validity of any information on this site and will not be liable for any errors, omissions, or delays in this information or any losses, injuries, or damages arising from its display or use. All information is provided on an as-is basis and confers no rights to any readers whatsoever. ***