Cars in superspeedway races are required to run tires with both inner tubes and 'inner liners,' which are actually small tires inside the standard tires. When the inner liner loses air pressure and that pressures becomes the same as that within the outer tire, the tire is said to have equalized and a vibration is created. Esses: On a road course, a series of acute left- and right-hand turns, one turn immediately following another.