Foot pump not working on Shraeder Valve

[Corleone]

i have never had a problem with this before however, tonight whilst attempting
to replace the tube i have found that when i try to pump some air into the tube to test it out
the foot pump is not having any of it. when i press down on the pump it remains rigid and no air is going into the tube.

i have a set of 3 new tubes and have tried it on another one but with the same issue

it works fine on a presta valve (i had just put a new innertube in on my hybrid and pumped that up with the same foot pump, and have tried it again on the other presta valve tyre and it works fine)

any ideas welcome

 

[User6179]

If I change between presta and shraeder on track pump I have to open it up and turn a part over on the connecter.

 

[Corleone]

I made sure to undo the nozzle on the connector to no avail - i just tried it on the tube which had the puncture and it works fine on this one (obviously it has gone down again now)
i assume i have a dodgy batch

 

[deptfordmarmoset]

So, it sounds like the valve isn't opening. Can you poke around a bit to see whether you can free up the pin thingummy?

 

[Tim Hall]

Are you pushing the pump head on far enough? Schraeder valves rely on the pump head pushing the pin in the valve in, to allow the air in. If the tube is flat you may need to place a thumb behind the valve to give a bit of resistance. Wetting the valve stem to lubricate it also helps.

 

[PGTips54]

I have an RAC footpump that I use on my car and my van.
On the car the Schraeder valves have a long brass thread and the pump fits and inflates ok.
On the van the Schraeder valves have a shorter brass thread before there is an outer rubber sleeve, which increases the valve diameter from this point. This prevented the pump head being pushed onto the valve far enough to allow the pin in the head to depress the pin in the valve.
Consequently, (having pressed the lever on the pump head), the valve would not open and I could not inflate the tyre.
I have overcome this by carefully chamfering the orifice in the pump head so that it will fit over the outer valve sleeve far enough for the valve to open. I used a 12.5mm (1/2") countersink bit in a cordless drill and took great care not to drill too deep or slip and cut my hand.
Valve stems are an overlooked but critical component as they are subject to huge centrifugal forces. I once had a puncture due to one rubbing on a wheel trim.
I know I'm talking cars rather than bikes but I hope this posting proves to be informative.

 

[Conrad_K]

I've been working on cars and motorcycles for the last fifty years. Until recently, I had my own tire mounting and balancing machines. I've worked with a lot of Schrader valves.

It wasn't until earlier this year when I got into 'cycles that I started running into problems with Schrader valves. I have several air chucks and tire gauges and five tires - a bike and a trike.

No air chuck or tire guage will work with all five tires. In most cases, only one of them will work with a given tire. The tire on the back of the recumbent was like that. Since the panniers made getting to the valve stem hard to get to anyway, I replaced the tube. The new one would also work with only one chuck and gauge, but different ones.

I have no idea what's going on with all this.

 

[Dogtrousers]

Bike schrader valves not made to the same tolerance as auto ones maybe?

 

[Conrad_K]

I have no idea. There seems to be a marked lack of standardization on bicycle bits (tires!), but given how old bicycles are, any given bicycle standard is probably senior to any similar motor vehicle standard.

Which is fine, except annoying to bicycle newbies like myself.