Dunlop valve

The Dunlop valve, (also called a Woods valve or an English valve) is a type of pneumatic valve stem in use—mostly on inner tubes of bicycles in many countries, including Japan,[1] Korea, India, Pakistan, Sri Lanka, most European countries, and a number of developing countries. The Dunlop valve has a wider base than a Presta valve, similar enough in size to a Schrader valve to use identically drilled valve holes in rims,[2] but it can be inflated with a Presta valve adapter.[3] The inner mechanism of the valve can be replaced easily, without the need for special tools.

Dunlop valve stem
Original plug
Modern plug

The Dunlop valve originally used a tight rubber sleeve (see illustration of "original plug") which had to be forced open by air pressure while pumping, but modern Dunlop valves use a different plug (core), making the valve as easy to pump as a Presta valve.

The inventor was C. H. Woods. It superseded Dunlop's original valve for pneumatic tyres.[4]

Dunlop valves are uncommon on bicycles in the USA, where either Presta and Schrader valves are used.

Dimensions

External thread: 0.305 in (7.747 mm) x 32 TPI (1⁄32 in or 0.7938 mm pitch)

See also

References
  1. "Japan Cycling Navigator:Information: Bikes in Japan: Tyres and Tubes". www.japancycling.org. Retrieved 1 June 2009.
  2. "Inner tube buying guide". 8 October 2018. Retrieved 10 October 2018.
  3. Sheldon Brown. "Glossary: Woods Valve". Retrieved 1 December 2010.
  4. Moulton, Dave (21 August 2007). "John Boyd Dunlop". Dave Moulton's Blog. Retrieved 9 January 2013.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.