Eli5: why some racing tyres are slicks and working better than thoses with grooves but road car tyres works the opposite way??

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Eli5: why some racing tyres are slicks and working better than thoses with grooves but road car tyres works the opposite way??

In: Engineering

The difference is that road car tires have to work in wet conditions, and slicks are downright dangerous when there’s water on the road. Because they can’t channel water away from the contact patch, they offer very little grip on a wet road and hydroplane easily.

That’s also why racing cars don’t use slicks on wet tracks.

Road tires have to account for weather conditions. Racing slicks are designed witout grooves because they only race on dry flat asphalt. Not having grooves causes the tire to heat up faster and grip the asphalt better.

Because race tracks are clean dry asphalt. The grooves in tires allow water to pass through a bit allowing the parts that stick out to make good contact with the road when it rains. Slick tires in the rain wind up hydroplaning almost instantly making them very dangerous.

When cars are raced in the rain they swap out for grooved tires.

Because in a racing car, “better” means “faster” while in a normal car “better” means “better stability & control in all weather.”

Slicks are the fastest option for dry road. When it rains racecars will also have grooved tires to prevent hydroplaning (grooves are slower than slicks but you’d rather be slow than spin out and crash)

Normal cars have to be able to drive well in all conditions- sun, rain, even snow. There is not as much pressure for tires to be as fast as possible because, well, most people are driving near the speed limit anyway. On the other hand, there’s a lot of pressure for tires to have good stability, since driving with slicks in the rain and snow won’t get you very far.

So it just comes down to your definition of “working better.” For a race car, “working better” means “having optimal speed” so you choose slicks (weather permitting). For a normal car “working better” means “having optimal control” so you choose tires with a tread.