Quote Originally Posted by Running Mommy
It may be your pump! IF you have a pump that has a head for both presta and schraeder valves, it may be the pump. Occasionaly my pump will not recognize that I just inserted a presta valve, and it blows air out the other side!
I thought I was nuts until my husband had the same problem with it. I guess there is a little mechanism inside that doesn't always work?? Because it does it every once in awhile, but for the most part it works. Frustrating for sure!
I could see where it seems like it's taking air out because the pump is pressing on the valve and so air is being released.
Anyway, that's my best guess. Sorry- no real "answer" for you!

Hmmmm...I think I'm gonna go find a presta specific pump then. I don't need agrevation like that...it completely through me off my grove for getting ready for the ALC...

Now to work on riding down hill.