Presta Valve

[gaz]

Had my first puncture this morning on my new road bike which has presta valces which i have never used before. I fixed the puncture in no time and was ready to put my tube back in the tyre. attached my pump (which screws on to it) pumped it slightly but when i went to unscrew my pump from the valve, the valve core unscrewed from the shaft that is connected to the tube. No matter what i didn't i couldn't get the valve core to stay connected to the shaft.

Any ideas on what to do in this situation? at present i'm stuck with a wheel i can't inflate!!

 

[SimonC]

Fit a new tube, now that youve knackered this one

 

[SimonC]

What kind of pump is it, never had one that screws onto presta valve, usually just push on.

 

[gaz]

It's a specilaized hand pump with a pressure guage. I will have the same problem with a new tube.

 

[4F]

Normally the pump will have a lever. You push the pump on the valve, pull the lever which creates a seal around the valve.

I think you will find the screw on the valve attachments is for schraeder valves ie the car type

Exactly which pump is it that you have ?

 

[gaz]

no leaver..

http://www.specialized.com/gb/en/bc/SBCEqProduct.jsp?spid=25948&eid=5134&menuItemId=10834

Thats the pump i'm using, i'm thinking about picking up a track pump on the way home. perfect excuse!

 

[addictfreak]

Not sure how you have managed that! The worst I have done with a presta bend the bit that goes into the valve stem.

 

[4F]

no leaver..

http://www.specialized.com/gb/en/bc/SBCEqProduct.jsp?spid=25948&eid=5134&menuItemId=10834

Thats the pump i'm using, i'm thinking about picking up a track pump on the way home. perfect excuse!

See what you mean

 

[ianrauk]

i have the same presta tubes where the valve unscrews. Only found this out when i had a puncture on the FNRttC. Went to take the cap off the tube and I unscrewed the valve. Just screwed it back in and inflated with my pump as usual. They are Continental inners.

 

[Dave Davenport]

I've found that once the valve inner has come unscrewed you need to nip it up with pliers to get it tight enough to stay put when disconnecting a pump.

 

[gaz]

I've found that once the valve inner has come unscrewed you need to nip it up with pliers to get it tight enough to stay put when disconnecting a pump.

I'll try this when i get in. *fingers crossed*

 

[Bay Runner]

I find these values very delicate too, broke one the other day fortunately I was at home. I had to replace the inner tube.

I now use a presta adapter (Only cost a quid)which seems to give better protection - connection than using the presta connector on my floor pump

 

[dudi]

ohh, maybe that's the problem i have with a 3 day deflating puncture in my rear wheel...
I'll get the pliers out and try to tighten it up.

with your pump - will it work if the pump is only screwed on to the valve a few turns? The less it's screwed on, the less likely it is to take the core out when unscrewing.

 

[gaz]

worked the first time when i tested it, but then as soon as i got the pressure up, the same thing happened and all the air came gushing out. damn depressing!

 

[gaz]

just bought some new inner tubes (with the valve connected to the shaft) and a track pump that doesn't screw on..

what should have been a 5 min job, turned into 2 and a half days!!!