The purpose of tire valve caps

The purpose of a tire valve cap is to protect your valve from dirt, dust and other particles which can enter the outside of the valve, potentially jamming it or contaminating the valve’s core. Tire valve stem caps also provide a backup seal to prevent air from leaking and maintaining pressure inside the tires. How? The rubber seal inside the tire valve cap closes the gap between the cover and the valve stem and make an airtight seal. This helps prevent air from escaping from a slightly leaking valve. In addition, the rubber acts as a cushion between the cap and the valve stem, damping the vibrations to prevent the cap from loosening and falling off. All of Sparkle Rider’s tire valve caps are constructed with a copper nut and rubber O-ring seal within the outer casing of the cap. Unlike caps made completely of plastic, metal valve stem caps can withstand minor impacts and are much more durable. However, they are not recommended for vehicles equipped with TPMS (tire pressure monitoring system). One of the reasons is that the TPMS valve stems are typically made of aluminum and when capped with a metal cap can fuse with the cap.