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View Full Version : Flat Tire...can't pump air in?



VeganBikeChick
08-14-2011, 04:43 PM
So my front tire was low on air...I tried to pump it up using my $25 REI floor pump...I wasn't getting any air in and the pump kept popping off of the valve. I thought the pump was defective since it was a cheapie and I hadn't had problems with it popping off the valve before. I went ahead and put a new tube on the bike and tried inflating that one....pump popping off again, no air getting in...

So I returned the pump and got a new one... This one screws onto the valve. I again attempted to pump up my (now new) tire tube, and and meeting resistance immediately and the gauge is reading 160 on the pump so I'm not attempting any more, but not getting air in the tire either...Thoughts??

pll
08-14-2011, 04:49 PM
I think the Novara Carema comes with presta valves. After opening in the valve (unscrewing the valve cap), sometimes you need to break the seal by depressing the top and letting a little bit of air out. Then you can pump. To see a presta valve open, check the top picture from this page in Sheldon Brown's web site: http://www.sheldonbrown.com/brandt/presta-schrader.html

Becky
08-14-2011, 04:52 PM
I don't know if this is what's happening to you or not....

Sometimes, my pump doesn't immediately seat on the valve when I first put the head on and pump. If I wiggle the head just a little, I'll hear a "tick" and the pressure gauge drops. After that, I can pump normally.

You could also try unscrewing the valve and giving it a quick tap to unstick it before pumping...

Velocivixen
08-14-2011, 04:53 PM
Do you happen to have Presta valves on your tubes? Do you know there are 2 different types of valves? So if you don't know, there are valves that look like the ones on car tires and they are called Shrader valves. You just hook up the pump and pump them up. Presta valves (google for an image if you like) has a metal tip that you must unscrew before air can go in or out of the valve stem. I don't mean the black plastic cap that you screw on, I mean a metal tip that unscrews which allows air to pass in/out. Sounds like you could have a Presta valve that you have not unscrewed. That would explain why no air is going in.

Velocivixen
08-14-2011, 04:56 PM
As an aside, we have a great floor pump that had one side for Shrader valves and the other side for Presta valves. Well it worked terribly for my Presta valves on my bike, so instead of purchasing an entire new pump, the bike shop sold us just the end piece with hose and it is a one size fits all (both types of valves) and it goes on great. It's not a screw on type, but a clamp type. Problem solved.

Muirenn
08-14-2011, 05:05 PM
First, make sure the nozzle assembly is seated properly. The innards (gasket?) can become loose. The raised part of the gasket should be inserted into the inner assembly, with the flat portion visible when you first unscrew the nozzle. Hand tighten the nozzle to the right once you verify the gasket is inserted the correct way.

Just play with it a little if you are not certain, but look at it before you remove it.

Next, make sure you:

1. Open the Presta valve on the tire all the way by unscrewing to the left.

2. It's easier for a lot of people to rotate the wheel until the Presta valve is in the bottom portion of the rim (so sticking up), rather than on the top or sides.

3. Make sure the large pump handle of your floor pump is all the way in, or closed. This ensures there is no excess air in the pump hose; excess air in the hose makes it harder to get a connection.

4. Keep the lever of the pump nozzle closed until after you put the pump on the presta valve. After you feel/hear it pop into place, open the lever of the pump nozzle. If you open the nozzle lever first, it may work, but pop off a lot of the time. And it's more difficult. After you finish pumping, close the lever. Then remove the nozzle from the presta valve. Tighten the presta valve. Cover with valve cap.

Edit: I had to figure out each of these steps on my own. Sigh.

But basically, either the nozzle assembly needs to be seated and tightened, or excess air pressure in the pump is making it impossible for you to put air into the tire, becasue the pump needs to be completely devoid of air and closed when you hook it up.

pll
08-14-2011, 05:11 PM
Here is an excellent video with Georgena Terry showing how to pump a tire with a presta valve: http://www.youtube.com/watch?v=9byRp9e2USU

VeganBikeChick
08-15-2011, 10:29 AM
I am such a goof!! Completely forgot to unscrew the Presta valve before attempting to inflate the tube. I've been filling my tires 2x/month at least and can't believe I forgot such a simple thing!

Thanks for all of the replies, TE. You're the best!

gbunker
08-15-2011, 10:34 AM
I am so glad to learn that I am not the only one who has done this! :D
Gillian

trickycoolj
08-15-2011, 10:46 AM
I bought a cheapie pump at Target last year and couldn't figure out how to get it to work this year. Went and bought a nicer floor pump at the LBS and actually looked at the tag before tossing it. Turns out the nozzle lever operates opposite of every other one I used as a kid, sticking up to pump, folded down to put on/take off. Whoops. :o On the plus side, this pump is supposed to work on both types of valves without adapters that I'd probably lose!

Velocivixen
08-15-2011, 11:14 AM
@VeganBikeChick, no worries. I'm glad it was something easy to deal with. (You could always say you were just "testing" us! lol)