How Tyre Pressure Influences Vehicle Performance

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Tyre pressure seems like such a small thing, and most people believe they don’t even have time to deal with it. However, it has an enormous effect on the safety and performance of your BMW. Checking your tyre pressure monthly is one of the simplest ways to keep the tyres in good condition, as it helps them wear more evenly. Here, you’ll learn more about tyre pressure and its importance for your vehicle performance.

Why is Proper Tyre Pressure so Crucial?

When tyres have proper air pressure, it helps to distribute the vehicle’s weight evenly across the entire tread pattern, ensuring the stability of the tyre and the vehicle itself. If a tyre is under- or over-inflated, it isn’t as stable, and stopping, cornering, and handling are adversely affected. Over time, the tyre will show signs of uneven wear. An under-inflated tyre tends to show its wear on the outer edges, while over-inflated tyres wear in the middle. In either case, incorrect air pressure means faster-wearing tyres and less money in your pocket. After all, no one wants that!

The Risks of Over- and Under-Inflation

Under-inflated tyres flex more during braking and cornering, and they do not respond as fast as they would with proper air pressure. Therefore, you’ll lose some of the safety and performance benefits the manufacturer built into the tyre. An over-inflated tyre is just as dangerous. It may lose traction because the tyre’s shape becomes deformed due to excessive pressure, diminishing its contact patch with the road.

Over-inflated tyres are more vulnerable to damage. They’re much stiffer and they may not react well to common road risks such as potholes. Furthermore, over-inflation gives even the most luxurious BMW a noisy, harsh ride.

Check Pressure Frequently, When Tyres are Cold

At AutoCraze, we recommend that drivers check their vehicle’s tyre pressure at least one time per month, and anytime you’re planning a road trip. It’s best to check the pressure when your tyres are cold, such as before you leave for work in the morning. Driving generates quite a bit of heat, and as we all know here in Australia, things get quite hot during the day. All of these factors can temporarily increase tyre pressure, and as such, you will get a more precise reading when your vehicle’s tyres are at their coldest.

And, if you were thinking of ‘taking the short way around’, there’s no such thing as a visual pressure check. It’s nearly impossible to tell whether a tyre is over- or under-inflated by simply glancing at it. Use a good-quality tyre gauge, and if needed, adjust the pressure to the level recommended in your owner’s BMW manual or the vehicle’s door placard. This placard is typically located on the driver’s door, and it offers a range of important info about your tyres, such as proper pressure, speed and load ratings, tyre size, and much more.

Going Off-Road

When traversing rough terrain, deep sand, or mud, many off-road enthusiasts will decrease their tyre pressure to increase contact with the ground. They typically decrease speeds as well, because their tyres become less responsive as far as stopping and steering are concerned. However, it’s important to be careful; removing too much air may damage your tyres or cause the beads to roll straight off the wheels. If you’re going off-road, you must remember to add air before hitting the road to go home.

Rock Crawlers

Here, off-roading is taken to an extreme level. Rock crawlers love driving over tall rocks, steep ledges, and other rugged features. Decreasing tyre pressure makes the tyres pliable and soft enough to conform to the rocks’ shape, increasing traction and smoothing out an otherwise rough ride of your vehicle. In some cases, a rock crawler may decrease their tyre pressure to single-digit numbers!

Autocross and Road Racing

As with the other sports mentioned above, the goal is to maximise the tyre’s footprint on the ground. During a road race, tyres get quite hot, increasing their pressure, and race drivers compensate by continually measuring the hot pressure and fine-tuning it to get the best performance possible.
Autocross races are usually short enough so that hot pressure is not as much of a factor, but every race driver must consider other factors such as track surface and air temperature. It’s quite a complex process, and it requires constant measuring, modification, adjustment, and checking to achieve the quickest lap time. With all that, aren’t you glad, as a street driver, that you only have to check your tyre pressure once per month?

In Closing

As we’ve shown here, tyre pressure has a substantial effect on various facets of a vehicle’s performance, whether it’s on the road, off-road, or on the track. No matter what you’re doing with your car, AutoCraze has the best rims and tyres for you.