Presta-to-Schrader Valve Adapter

What is a Schrader Valve?

The Schrader valve, also known as the American valve, consists of an externally threaded hollow cylindrical metal tube that is typically coated in rubber, and into which a valve core is threaded. The valve core is held in the closed position by an internal spring.The Schrader valve is used on virtually all automobile tires and motorcycle tires, as well as some bicycle tires.

What is a Presta Valve?

The Presta valve, sometimes called the French valve, is typically used in high pressure and performance bicycle inner tubes. It is made of an outer valve stem and an inner valve body, often with a lock nut often securing the stem at the wheel rim. The smaller hole for a Presta valve makes it possible to have extremely narrow wheels without losing strength in the wheel. The air pressure in an inflated Presta tire holds the inner valve body shut. A small screw and captive nut at the top of the valve permits the valve to be screwed shut and ensure that it remains tightly closed.

Why do I need an adapter?

If you carry a hand-pump, and/or C02 inflator while you ride you likely do not need an adapter. However, filling up a Presta-valved bicycle tube at an automobile filling station requires an adaptor, while a Schrader-valved tube does not. Any further questions?