Tire inflation?

[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!

[Geonz]

It makes a difference on my bike where the valve is. If it's down between 5 and 7 o'clock, I can't seem to get it to work. I'd have thought pointing down owuld be best... but 11 or 1:00 work best. Getting just the right angle seems to be the trick. (I have the same issues a little bit with the car tires... but my plan is to take them in tomorrow ...)

[shadon]

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.

[mellic]

I would take Geonz advice before you buy a new pump. Turn your wheel so the valve is at the bottom and then try.

[Geonz]

At the top! At the top! (Or wherever it hasn't been... but for me, the bottom was where it didn't work.)

[bcipam]

When you attached the pump nozzle, did you set the "hold" lever? In otherwise, the nozzle goes on and you usually pull the lever up (or down depending on the pump) to latch the nozzle on adn hold in the air. If you don't air comes out.

[Bella]

I also have a dual Schraeder/Presta pump and succeeded in deflating one perfectly good tire. It was nothing but a struggle to re-inflate. I haven't found the magic formula yet - but I dare say I don't feel like experimenting.

[Dianyla]

I've also got the (notso)Smarthead pump that senses schrader vs. presta head. I found that if I don't push the presta valve in far enough it tends to just leak air out as I pump, eventually deflating the tire. I think those pumps work by assuming that a schrader valvestem will only go in about 1/4" inch and a presta will go in more like 3/8" or even more like 1/2".

[maillotpois]

When you attached the pump nozzle, did you set the "hold" lever? In otherwise, the nozzle goes on and you usually pull the lever up (or down depending on the pump) to latch the nozzle on adn hold in the air. If you don't air comes out.

This can be tricky to get right - and every pump is different. I'll bet this was what the problem was. Shadon, you're going to have to figure out how to get your pump locked onto the valve right.