Maelochs

Wrong. As the pressure drops, yes, the nut stays pressed against the rim but not with however many PSI of pressure. Maybe you forgot—-rubber stretches. I can pull the stem up easily—- no pressure holding it—-and remove the nut easily.

You don’t use knurled retaining nuts, I do. You don’t know what you are talking about—- sorry but it’s a fact. Having changed who knows how many tubes over decades of commuting and pleasure-riding, and Never having had one stick …. You are doing it wrong, or just imagining stuff. IRL the nuts are tightest when the tire is fullest.

terrymorse 

I can say with confidence that I am not the only person to suffer a sticky valve stem nut. This problem was reported more than once in good old rec.bicycles.tech.

“The deal is that when the tube is pressurized, the valve is forced down hard against the rim, but when it goes flat and the pressure is released, the valve retracts a bit, causing the nut to get tighter.”

—Sheldon Brown, r.b.t 2003

terrymorse 

That makes no sense at all.

The valve stem obviously is protruding the farthest when the tire is fully inflated. Try pushing the valve into the rim under full inflation. You have to overcome the pressure pushing at the base of the stem, I’d guess roughly 40 pounds.

When the tire is deflated, that 40-some-odd outward force goes away, and that little stem nut that you tightened down under pressure is now tighter.

Maelochs

Please read better. I inflate the tire to whatever pressure and tighten the nut. The valve is pulled as far as 80–120 PSI allow.

When the tube is less full I can easily lift the stem a little.

I know some folks worship Sheldon Brown, but I also know I have done decades of riding and changed hundreds of flat—this includes a stint as tire repairer on a cross-country tour with more than two dozen riders, plus decades of urban commuting in terrible conditions—and I have Never faced a stuck nut.

Not sure what is wrong with everyone else and don’t care. It has Never happened to me.

Sucks to be you guys, I guess.

Try gently lifting the valve stem …

Lombard

This is true. However, I have never had a problem unscrewing the collar. And my hearing is pretty good, yet I have never heard much less been annoyed by collar rattling while riding. A big nothingburger.

Lombard

Who wudda thunk??

genejockey 

No, silly - the point is not that it's a big hardship, but rather that they're unnecessary and I lose nothing by removing and discarding them. If you like 'em, great. I don't.

terrymorse 

Nonsense. Please consider a little physics:

When a tire is fully inflated, the valve stem is protruding as far as it ever will. Try pulling on the stem, it won't move. If you tighten the stem nut at this point, the stem will be held there at it farthest protrusion point when the tire is deflated.

Once the stem nut has been tightened under full tire pressure, you will not be able to "easily lift the stem a little" when the pressure is reduced, as the stem is being held at it's "as far as it ever will" protrude point by the nut that was tightened under full inflation.

Eric F 

I commented earlier that I have also had an issue with a stuck valve stem nut. On a tubeless tire, however, you don't have the option to leave it off.

Maelochs

Maybe you don’t understand physics or maybe you just use the word to lend weight to an empty argument.

Don’t cite “physics,” Do Science…. Go out to your bike and try it.

When the tube is smaller it does not push against the rim. Don’t talk—- Do It.

A stuck nut was cross- threaded or jammed.

It is Almost funny when smart people take a dumb stand and defend it.

terrymorse 

Horse. Water. <sigh>

I give up.

John Wick

I give up. sry.

wolfchild

Valve stem nut makes it easier to get an air chuck on the valve stem when inflating a tire. So they do serve an important purpose.

genejockey 

I don't find any problems with that, so they don't serve an important purpose. See how this works? The things you think are not universal.

livedarklions

I agree that it's very easy to pull the stem out from the rim when the tire is deflated. I wonder, though, if it is not possible that the nut might corrode on some stems making it stick in the "too far down" position. I'm with you, I've never ever seen one stick, but I don't know that I'd assume it was impossible--that seems needlessly contentious.

livedarklions

I've been known to push it up from the bottom by pressing on the tire, I must have applied at least 6 ounces of pressure.

livedarklions

The smaller the stakes, the bigger the quarrel.


Honestly, I think the usefulness of these is really dependent on what type of pump you use. I have had some that were basically useless in the absence of a nut, and others where it made no practical difference.

coffeesnob

Do those saddles make your butt look big?