When i get a rim job I tell her to stay away from my nuts... (but then again, I'm ticklish)
Oops, wrong forum...

I dont know what you guys are talking about, every tube i have ever bought comes with 2 nuts. I put on on the inside finger tight to the bottom of the valve stem and one on the outside against the rim. I have NEVER and i repeat, NEVER, had a tube pop on me from the valve stem tearing.

Just one manual I found.

dirtbikerida63, on 23 July 2012 - 10:08 AM, said:

Well so far I have a loose count of about 25 ripped out valve stems. I like the flexing theory, makes sense to me.

dirtbikerida63, on 23 July 2012 - 10:08 AM, said:

You haven't been riding long enough...

I have ripped out at least 5 having the nut against the rim, now i toss both nuts and haven't had this problem since

The only reason that the tube would rip at the stem was that the rim lock wasn't donig it's job (rim locks need replacing from time to time). I've always adjusted the nut to seat against the rim, but after reading the this post I'll not be doing that anymore.

A few weeks ago, my bike had a flat tire and I couldn't figure out why no matter how much air i pumped into it, none actually went into the tube.  I figured the tube ruptured however it was something else.  I'm guessing that I had my valve stem nut on tight against the rim and it ripped the valve stem halfway out of the tube.

I think i'll run it by the cap from now on.