Presta to Schrader valve adapter to pump racing bicycles up to 10 bars (148 psi).

thingiverse

Presta to Schrader Valve Adapter. The adapters I found on Thingiverse either leaked air or were too thin and broke after using twice, so here's an improved version. Features: - Easily reaches 10 bars (148 psi) for racing tires. - Excellent seal with the pump chuck since no external thread is used that leaks air. - Extra-long stem to prevent the chuck pin from pushing against the valve tip, making it hassle-free when connecting the pump. - Virtually unbreakable. -------------------- Information on Different Valve Types and Names: - Presta valve, also called Sclaverand or French valve, has the smallest diameter and is used on performance bicycles with small rims. - Schrader valve, also called American valve, is used on almost every motor vehicle worldwide. - Dunlop valve, also called English valve, uses the same thread (5V2) like Presta. The Valve Threads Follow a Special Norm, the ISO 4570. Details: http://www.iso.org/standard/30078.html and http://mdmetric.com/tech/thddat26.htm Presta Valves Details: - The external threads at the tip of Presta valves are 5V2, measuring 5.2 mm in diameter and 1.058 mm pitch. - The external threads on the main body of Presta valves are 6V1, measuring 6 mm in diameter and 0.80 mm pitch. - As the valve is closed with a screw, a cap on the valve is not mandatory. Schrader Valves Details: - The external threads on the main body of Schrader valves are 8V1, measuring 7.7 mm in diameter and 0.794 mm pitch. - The air chuck must depress the spring-loaded pin to inflate the tire. - A cap has to be used to prevent dirt from entering the valve. Valve /// ISO 4570 /// Diameter x Pitch Presta tip /// 5V2 /// 5.2 × 1.058 mm Presta stem /// 6V1 /// 6.0 × 0.80 mm Schrader /// 8V1 /// 7.7 × 0.794 mm