Make sure you do your valve cores up nice and tight. The screw on fitting can undo them from time to time as you remove the pump.
Lubing the inside of the screw on fitting with some grease helps too.
@Fatbiker started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Make sure you do your valve cores up nice and tight. The screw on fitting can undo them from time to time as you remove the pump.