By Shell on Aug. 03, 2021
As the final components in a car's engineering chain and the only ones that make contact with the road, tyres are more than just black and round – they play a key role in how a vehicle performs and drives, and even affect safety and fuel usage.
Getting a grip
As a tyre rolls, turns and squirms along the road surface, it generates friction, or grip, and this complex interplay has a wide-ranging impact on how a car behaves. More cornering grip, or 'road-holding', means a tyre can literally hold onto the road longer before it lets go and the car slides. More grip also means more of a car's braking power can be realised for shorter braking distances. It means better traction because more power can be translated into motion, not wheelspin. This is why the right tyres are so crucial. They don't just help a car drive better, they make it safer, too.
A fraction too much friction
The impact of tyres on car performance doesn't end there. Rolling resistance, or how easily a tyre rolls along the road, plays a part in how much fuel a car uses. The more rolling resistance a tyre generates, the more power (or fuel) is needed to overcome it.
Tyres also contribute to the finer aspects of a car's driving character by working with its suspension to soak up lumps and bumps. They can either increase or decrease noise levels, too.
Tyres are designed to work in a specified pressure range and running them at the wrong values can reduce road-holding, comfort and economy while increasing tyre wear. Tyres also lose pressure over time. For these reasons, pressures should be checked every two weeks.
What tyre is best for me?
Most tyres are made to deliver a mix of grip, comfort, quietness and durability that suits most drivers on most roads, wet or dry, most of the time. But because there's no one perfect tyre all of the time, you can also choose from a broad variety of specialised tyres with different strengths and weaknesses. High-performance tyres maximise a car's road-holding potential by using aggressive tread patterns, softer rubber 'compounds' and other measures to optimise grip. But they can wear faster, have higher rolling resistance and be stiffer and noisier than regular hoops.
Other tyres are marketed as a fuel-saving, long-life or noise-reducing choice and use harder compounds, unique tread patterns and other tricks to reduce rolling resistance, noise and/or wear, typically at the cost of sheer road-holding. Get into the 4WD realm and you can optimise tyres for specific surfaces and conditions.
Often the best replacement tyre is what you're already riding on – car makers go to some lengths to pick the right tyre for their cars – but if you're not happy with your current set's road-holding, comfort, quietness, durability or life, start asking your tyre retailer the hard questions. They're well placed to help you navigate the market's bewildering array of options and find the best tyre for your needs.