It’s a time honored tradition. Nascar fans and drivers converge on the track for the weekend and eagerly wait for the race on Sunday. That is, until Mother Nature intervenes, washing out the race and postponing it until Monday. This scenario plays out 3-4 times a year without fail; and each time, race fans inevitably ask why the drivers simply can’t run in the rain.
The answer depends on the tires on the car. Nascar tires are not normal tires. They have no grooves or tread, enabling them to get the most grip possible on dry pavement. These tires, called slicks, would not be able to hug the ground under rainy conditions. A film of water would form between the tire and the road, causing the driver to hydroplane, lose contact with the ground, and spin.
However, times are changing. Nascar introduced rain tires in the Xfinity Series, using them on 3 separate occasions at road courses. Drivers are able to race with grooved tires on these courses–the lower speeds create far less wear on the treads. On high-speed tri-ovals, however, rain tires would be worn out and ground down within a few laps. Nascar has rain tires on standby for Sprint Cup road course races, although they’ve never been used. Look for them the next time it gets damp at Watkins Glen, Sonoma, or even a short track like Martinsville.