I'm trying to locate a stand up tire pump with a pressure release system allowing you to remove the flip-chuck without letting out air from the inner tube. I'm finding that with the smaller 14" tubes, the air pressure drops so much that I have to slightly over inflate to allow for the loss when removing the chuck. There are decent pumps that have a pressure release system, but from what I have seen so far they are designed for the Presta Valves and I'm not sure if they will work with the Schraeder Valve on the Brompton. Has anyone seen such a pump? I'm not sure, but I think someone posted info on this but I can't find it.