Car & Driver magazine (April 2008), reporting on a simulated “test drive” of the Mach 5 Speed Racer prototype for the live-action movie, includes the following about the special tires:

“And thanks to a breakthrough in molecular application, these ADVAN Sports can change the [tread] compound in accordance to driving surface variations and driver stress levels. The change occurs through the application of RMS (remote mandible sensors) that are mounted on the headrest. Yokohama has discovered that the jaw muscles of the driver are instrumental in reading the subtle changes in stress while driving. The data captured by RMS is sent to the sensors mounted inside the tires in 1/1,000,000,000th of a second. The sensor activates a magnetic charge within the tire’s bead assembly, which then activates the compound to change.”

Magazine found abandoned after a flight cancellation at Boston Logan airport.