Do race car drivers weave around on the parade lap to heat their tires?
Dear Straight Dope:
When Formula 1 cars are on the parade lap, you often see them weaving side to side to put heat on their tires. Does this actually work, and if not, what does it actually do?
Race car drivers do weave, and they are trying to heat their tires. However, the object of weaving isn't to warm.
If you've ever seen a set of racing tires close up, you know how different they are from the tires on your family car. Racing "slicks" are just that, treadless tires. But they're not totally slick. The manufacturing process does leave some rough spots and a couple of slow laps scrubs the roughness and debris off the surface.
Equally important, tires aren't at maximum grip when cold and those first slow laps warm them up enough so that they do their thing when up to full speed--like in the nanosecond after the green flag drops.
When you see drivers weaving their cars back and forth, they're also testing to see exactly how the tires grip the surface, how the tires are setting up on the car, how the car is handling with these tires through the track. Sometimes a little suspension adjustment is needed as well; the driver can make that tweak from inside the car.
Dragsters don't have the time or space for laps, so they warm their tires up with chemistry. A solvent is poured on the asphalt and they spin the rear wheels in it before they go. The track is also heated. This warms everything up so they can have their millisecond of glory at maximum grip.
Don't try this at home, even if your commute to work IS like the Gatornationals.