Presta valve issue

[Trek-chick]

This happened to me twice last summer, although I wouldn't say that it broke off so much as SHOT off. Never found it either time. Using a Park floor pump both times. I chalked it up to the quality of the tube. I believe they were both Q-Tubes, so I avoid those now.

That's kind of what I was thinking. Poor quality tubes. This is the first time it happened to me with any of my three bikes.

[roadie gal]

This has happened to me before, too. I chalked it up to being in a hurry and not attaching the pump properly.

[tzvia]

Yep, aggravating. And these days, it seems that most tubes I find at the LBS don't have removable valve cores which makes the job of fixing it impossible. So I only buy tubes with removable valve cores, and I have the Stans No-Tubes core remover tool (super easy, put it on the valve, and turn) and a few extra valve cores. When this happens, I just unscrew the core and replace it. I even keep an extra in my patch kit because nothing is worse than fixing a flat, getting it all back together, and having the core break when you pump it up.

[jelee1311]

I have had this happen a lot. Not as much now as when I first started riding and I would get the wrong angle pulling off the pump. My husband got exasperated when I yanked off two valves in one day. I have a good pump but it is tight so now I'm very careful when I detach it I also push the valve and release a little air before I attach it.