Valves

[Canardly]

The valves on my road bike have decided they don't like my track pump and are refusing to work. I can undo them manually and the pins move easily. When I try and pump some air in I end up on the ceiling. What is going on?

[Canardly]

This is clearly one of those mysteries of the universe. Will try the lezyne and see what happens. 

[Tewdric]

Have the pins holding the lock lever on your pump head popped out one side?  Rubber grommet thing fitted correctly?  Can you pump a new tube ok? 

[Crumbling Nick]

Would have replied sooner but stopped at

When I try and pump some air in I end up on the ceiling.

I still don't understand what that means.

Withal...

Does the problem occur with presta valves on other bikes?

If it's a dual head pump , i.e. schrader & presta, does the problem occur with schrader valves as well as presta?

The question is whether it's the valves on the road bike, or the pump, or some unusual combination of both.

My (limited) experience is of a track pump that has gradually become leakier at the valve end. Surprisingly that's on both presta & schrader valves.

HTH.

[mrcharly-YHT]

This is almost certainly caused by the pump head not allowing the valve core to move down under pressure.

Either the rubber grommit has become deformed or you aren't pushing the head on far enough.

[jsabine]

This^.

When I've had this problem, removing the pump head and jiggling it has worked. It's also gone away when I've changed the tube. I've tended to assume that the valve stern is catching on the pump rubber in some way.