What is the first thing you do when you buy a car and want to make it stand out?
Racing stripes, tinted windows, a loud exhaust, or a pumping sound system are all fine options – but none come close to adding “mags”.
Light, magnesium-alloy wheels – known as mags on the street – are the go-to aftermarket part which can take your Citi Golf or Toyota Tazz from sensible small car to not-so-formidable street racer.
Nowadays, many cars come with alloy wheels as standard – which are often upgradeable to larger and fancier mags from the manufacturer.
However – whether you are buying a new car and deciding which model to select, or upgrading your second-hand ride with new wheels, you need to take note of how much tyres will cost you.
Bigger rims mean bigger tyres
While ostensibly elementary, it is not a given that car owners will know that getting new wheels often means getting new tyres.
The tyres on your car right now are a specific size that fit onto your wheels.
You can see the size of your tyres on their sidewall – and the graphic below from Tiger Wheel & Tyre provides an overview of what you need to know.
The main elements are the tyre width, profile (a ratio of how tall the tyre sidewalls are), and the wheel diameter in inches.
Other elements include the R symbol for a radial tyre, where the sidewall and tread are designed to function as two independent features.
The load index is also there, which details the maximum load each tyre can take. For example, a 91 load index translates to 615kg.
Finally, there is the speed rating letter. For example, the letter V translates to 240km/h.
If you car currently has a 15-inch wheel, it will be fitted with an 15-inch tyre. Naturally, if you upgrade to 17-inch wheels, you will require a 17-inch tyre.
Profile and width
The diameter of the tyre is not the only size element you must consider, though.
The width and profile of the tyre also play a part in how much you will pay for new rubber, as wider, lower tyres provide better on-road performance – at a higher price.
The best example of this is on high-end sports cars or super cars, which feature very wide tyres with low sidewalls.
This combination provides stability at high speeds, thanks to a wide tyre providing more rubber on the road and more traction. The low profile means less flex in the tyre sidewall, and also enables the fitment of larger wheels for styling and functional purposes.
A tyre’s speed rating will also be taken into account for performance vehicles, and can add more rands to the price tag.
To provide an indication of how tyre prices change depending on their size, profile, and width, we looked at the range of Continental tyres available from the Tiger Wheel & Tyre website.
Passenger vehicle tyres were considered, while run-flat options were excluded. The pricing per tyre is listed below.
- 175/65 R14 – R799
- 185/60 R14 – R949
- 195/65 R15 – R1,129
- 205/55 R16 – R1,375
- 225/45 R17 – R1,549
- 205/50 R17 – R2,149
- 245/40 R18 – R2,299
- 245/40 R18 – R2,799
- 255/35 R19 – R3,199
- 265/45 R20 – R4,699
- 295/40 R21 – R5,099
As you can see above, going from a 14-inch to a 21-inch option can mean paying over R15,000 more each time you need to replace your car’s tyres.
The next question, though, is how often will you actually have to buy new tyres for your car?
Pirelli states that, based on European statistics, the average lifespan of a normal road car’s tyres is between 25,000km to 50,000km.
This peaks at 75,000km “in the case of more laid-back driving”, but can fall below 10,000km “if the driver won’t give up on making the most of everything the car has to offer”.
This means if you drive your car from new to 120,000km in a “normal” fashion, you may have to change your tyres 3-4 times.