Tire Won’t Take Air

[Coach13]

So probably a dumb question but I’m a bike rookie so you’ll have to excuse me if it is. I have a tire on my bike that Is low on air, but will not take air from either a hand pump or a small compressor. I am assuming it is a bad valve stem as it will allow me to leave air out but not pump air in. Thoughts?

Are valve stems replaceable in bike tires like they are in car tires?

 

[Doug Briggs]

Is your tire tubeless or does it have a tube? If the former, the stem can be replaced. If the latter, you replace the entire tube to replace the stem.

 

[graham418]

Is it a presta? did you unscrew it?

 

[Doug Briggs]

Is it a presta? did you unscrew it?

Good call. Presta is more complex than Schraeder, but stronger.

This could be more info than you need, but better too much, than too little.

 

[Coach13]

Is it a presta? did you unscrew it?

It is not a presta.

 

[graham418]

If its a cheap chinese tube with a schraeder valve, just throw it out and get a new one

 

[Doug Briggs]

Schraeder valve cores can be replaced. Your auto or bike mechanic could help, but as @graham418 alludes, it is probably easier and cheaper to just replace the tube. Tubes are relatively cheap.

 

[Coach13]

Thanks guys

 

[cantunamunch]

Sometimes it helps to tap the valve mechanically before putting the pump head on. Presta you just tap with your finger on the narrow 'post';. Schrader you use a tool like the dimple on the back of pen type pressure gauges.

 

[Plai]

Stupid question: did you lock (flip the switch on) the bike pump nozzle? See Doug's posted video at/around 1.30
.
Personally I'm voting for replacing the tube, but have had to coach people through the locking of the nozzle.