After Joe Blow floor pump that didn't last a year, I ordered a SKS Rennkompressor pump. Definitely better quality construction that the JB but having just tried it for the first time, I have a question. The EVA chuck is nice, however when I undo the latch after pumping, it seems to loose a significant amount of air very quickly. Any recommendations or techniques to avoid this? -Thanks

Are you sure its not the compressed air coming out of the pump hose?

I just picked up a pressure gauge to check. Yes, some of it is probably from the hose but unless the pump gauge is off by 10 PSI, air does seem to be escaping from the valve since its lower by that amount when I check it with the gauge.

Great pump construction, but I gave up on the head. I cut it off and installed this http://www.alexscycle.com/misc-/other/hirame-pump-head-yoko-hose-band.html Couldn't be any happier!

I have a Specialized Air Tool Pro pump with a built-in air pressure gauge. After pumping up a tire, and unlatching the pump attachment from the valve head, I can hear a swift gush of air escaping. I've always assumed that this is air escaping from the valve as the valve shuts itself by air pressure compressing that little round, black grommet inside it. If I put a pressure gauge on the valve immediately afterward, I notice that the pressure reading is about ten pounds less than the pressure reading was when I released the pump attachment. High pressure tubes, and an instant gush of air as the valve seats, looks like it causes a ten pond pressure reduction instantly. I always pump the tire up to ten pounds over the intended pressure, and let the valve bleed ten pounds away when the pump is disengaged.

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Well you are also losing air because the hose fills back up with air from the tire when you put the pump head on again. I think you would see a loss of pressure doing this no matter what pump you are using.

My LBS they had a Silca chuck, which I bought. Cut the hose and put in on my Joe Blow. Pumped it to 120 psi and noticed very little air loss when removing the chuck. Checked it with the gauge and sure enough it was dead on 120 psi. Unfortunately the connecting arm doesn't go far enough into the hose. The opening in the hose is a little too small. I like everything else about the SKS but I think I'm going to just get a Silca pump.

I got a floor pump from tesco supermarket chain . It cost around £10 pound and is brilliant .