Technical Dictionary

Sprung weight

The parts of a car that are supported by its springs, including the frame, engine and body.

Valve

A device that lets air in or out of a tyre. It is fitted with a valve cap to keep out dirt and moisture, plus a valve core to prevent air from escaping.

Variable Contact Patch

A system that maximizes the contact patch area during cornering through a combination of asymmetrical tread patterns and underlying belts.

Variable Integrated Pitch

The process of varying the size of tread blocks around the circumference of a tyre to minimize the noise generated by the tyre as it rolls.

Variable Thickness or Bidirectional Sipe

Two types of sipe technology that increase the rigidity of the tread under loaded conditions, such as cornering, braking, or accelerating. This technology allows tread block surfaces to lock together (in both longitudinal and lateral directions), resulting in precise and responsive steering, short braking distances, and improved transmission of engine torque to the driving surface.

Viscous Planing

Can occur just after a rain shower wets down a dry road surface. Oil on the road surface migrates to the top of the layer of moisture, and can be very slippery, even when the layer of moisture is very thin. Continuing rain lessens the condition by washing the oil away.

Vulcanization

The irreversible process of heating rubber under pressure to improve its strength and resilience.