C Arnold wrote:
In less than a week's time I've had two inner tubes fail when the valve
stem pulled out of the inner tube. The tubes have Presta valves and I'm
using a Park Tool tire pump. Any thoughts as to what is going on here?
Besides being annoying it is starting to get expensive. And yes I'm
releasing the lock before trying to pull the pump fitting off of the
valve stem.


Some brands seem prone to this.
If you have more of the same tube, leave the locking nut loose or skip
it completely -- it'll help some.
Try a different brand next time .

David