Pumping up tyres

[geopat]

I fit the track pump to the presta valve and lock it but 9/10 times air from the pump seems to just leak out at the valve when I start pumping. The pressure reader then shows the pressure reducing massively but the tyre is in fact inflating. On the odd occasion I have no problem and air goes in and reading goes up. Must be some kind of connection problem.

I know I'm a muppet so no cheeky comments thanks.

 

[Baggy]

When you've unscrewed the little nut on top of the presta valve, do you push down on the "spike" before you put the pump attachment on?

 

[geopat]

When you've unscrewed the little nut on top of the presta valve, do you push down on the "spike" before you put the pump attachment on?

Yes, done this to ensure there was no blockage and then let some air out. Still happened.

 

[Baggy]

Hmm, in that case, no idea I'm afraid! Could be a faulty pump.

 

[Norm]

Does it happen with all tyres / valves or just one? Are you pushing the pump's nozzle down hard enough onto the valve?

 

[HLaB]

I occasionally find some pumps pernickity and you have to fiddle with them to get the pump to work its usually my cheap aldi and lidl ones. I just have put it on and off until I get it to lock and make sure the valve is fully inserted. Whereas my slightly dearer Ed Co op and cyclaire go on nearly first time. I don't think I'm doing anything wrong in the first instance its just the quality of pump.

 

[e-rider]

the answer depends on your pump but generally you are not pushing it on far enough.

it might not be possible to get it on far enough for a number of reasons depending on how the end of the pump is assembled

if it has a screw plastic cap covering a rubber bit, loosen it off half a turn

 

[geopat]

Thanks all, will push it on a bit harder and see if that works.

 

[screenman]

Bit of washing up liquid on the valve will help it slide on easier, or even (cover your ears if you do not want to read this) a bit of saliva.

 

[oliglynn]

I seem to get a similar problem, attach the track pump on presta valve side, pump, and it won't open the valve & inflate the tyre- just builds up a crazy pressure very quickly in the air line. When that happens I use a schrader to presta converter and use the schrader side of the pump - a bit more fiddly but works every time! Will try loosening off the screw plastic cap & see if that works...

 

[Angelfishsolo]

My mates pump has the same problem. If I push the side of the pump head inwards the air loss stops. IMHO it is to do with the build quality of the Track Pump.

 

[oliglynn]

Mine's a Topeak joe blow II - gets really good reviews in most places ... maybe it's faulty?

 

[Davidc]

Try a smear of grease on the valve thread. Vaseline has sorted that out when I've had it happen.