Threaded vs. Smooth Valve Stems?

[winphoto1]

Being new to cycling, could someone please state the purpose of threaded valve stems? Is it to make it easier to put the pump on when a tube is new because the nut can help keep the valve stem from being pushed into the rim?

I had my first flat awhile ago and replaced it with a tube with a smooth valve stem. The pump slides on and off so much easier that I don't really see the value of the threads. Maybe I'm missing something.

Thanks for the responses!

[Bill2]

The threaded ones suck. The knurled nut is supposed to keep the valve stem in place better. Love the smooth ones- the rubber seal in the pump head works so much better with them, and I've never had a problem with the valve stem moving out of position.

[kmunny19]

I don't really see the value of the threads. Maybe I'm missing something.

you are not.

[Hooben]

Agreed, the asian companies are just pumping out stuff...nobody knows why. It's like the newbies who ride around with the plastic cap on the presta valve and the round nut around the presta stem...nobody knows why?

[Peanya]

I'm a noob who still uses the nut and prefers threaded. I don't like the smooth ones either.

[Jay Strongbow]

If I'm stuck and need to buy a tube where the stem is a little short for my rims I like the threaded ones because they're easier to pump up when flat but other that that I don't see much reason to care which I have.

[Cheerios]

My pump prefers the extended and threaded.

[Mootsie]

My pump prefers the extended and threaded.

+1 if you have tires that take higher pressures like Vreds, you really want the threaded stems. They stop the pump from "blowing off".

[velodog]

Threaded stems are awful hard on the pump head. They will chew up the rubber gasket to the point that it will blow off the stem before reaching pressure.

[MR_GRUMPY]

The reason behind the threads is that the first inner tubes that used a presta valves were used on 27X1-1/4 or 27X1-3/8 tires that were pumped up to 60 -75 psi. With these low pressures, after time, the tire would whift on the rim, and cause the presta stem to tear. The threadded nut kept that tube from shifting, and saved the tube from tearing.
Modern clinchers are run at higher pressures, so you don't have that problem anymore.

PS. I recomend MTB's to use a threadded presta stem for the reason mentioned above.

[Special Eyes]

Agreed, the asian companies are just pumping out stuff...nobody knows why. It's like the newbies who ride around with the plastic cap on the presta valve and the round nut around the presta stem...nobody knows why?

Excuse me? Sorry, I didn't know that was a requirement for experienced riders....

The Specialized tubes I use have a short length of thread for the round nut and the rest of the shaft is smooth. Perfect. And news for noobs, it's a good idea to use the round nut as it stabilizes the stem when you're jamming the pump head on and yanking it off, which you'll do dozens or hundreds of times in the life of a tube.. Keeps the stem from receding into the tire which can weaken the already fragile area of tube around the stem. I use the plastic cap, too. Shoot me.

[stleon2]

Threaded stems are awful hard on the pump head. They will chew up the rubber gasket to the point that it will blow off the stem before reaching pressure.

So that's why my Blackburn pump took a dump...

[Mootsie]

Threaded stems are awful hard on the pump head. They will chew up the rubber gasket to the point that it will blow off the stem before reaching pressure.

9 years and still going strong on my pump gasket with threaded stems.

[Kuma601]

Smooth stems are much nicer on-off. The threaded stems are a conspiracy with the pump manufacturers.;) The rubber grommet in the Joe Blow head needs to be replaced somewhere around 14-16 months time. No big deal at roughly $2 each. The Silica chuck, the rubber grommet has been durable, I have changed it twice in 20 years. The last one didn't seem as well made though.

[Mapei]

I may be a noob, as I've only been using clinchers since 2000, but I greatly prefer threaded stems, locked with a nut onto the rim. As mentioned above, the threads make it less likely the pump head will blow off the stem...a situation that invariably puts my as yet unshod tootsies in danger. With the stem screwed tightly onto the rim, the stem automatically centers itself in the rim hole, and then doesn't shift (something that happens at practically any pressure for me, especially when I've followed the all-important note to talc the tube). When the tube is entirely deflated, it is much easier to get the pump head onto the stem when the stem fastened down.

At any rate, yes, I'm clumsy. And to hell with the stupid little grommet. They're cheap.

[Mr. Versatile]

Smooth stems are better IMO. They don't chew up the pump head, the pump head seals better, and also goes on & off easier.

Worried about pushing the stem into the rim hole when inflating? Put the pump head against the stem and your other hand around the tire behind the stem. When you push the pump head on apply opposite pressure with your thumb or the heel of your other hand.

Never pull the pump head off the stem. Ever. Place both hands around the tire behind the stem & use your thumbs to push it off. It'll just pop right off without ripping the stem off or making you crunch your hand into the spokes.

[looigi]

Smooth stems are more aero...but I prefer them anyway.

[Matador-IV]

Smooth stems are more aero...but I prefer them anyway.

But threaded are more lighter.

[moschika]

which ever ones are cheaper are the ones I prefer. given the same price, I prefer the threaded with the nut. my floor pump sits more secure and doesn't blow off like it does with the smooth valves. I also find the nut does make it easier to pop the pump head on then with out. after several years of pumping my tires, I'm barely getting shredded washers.

[Harryquinn]

Smooth valve stems for me every time. I've never had any problems with my floor pump blowing off them under pressure and sliding the pump off after inflating is so easy.

Contrast that with the hassle I get from the threaded valve inner tubes that came on my new Scott CR1 Pro. It's a drag to push the pump head onto the things but a real chore getting it off again. I almost changed them immediately for smooth-stemmed ones I carry as spares but, being a cheapskate, decided to wait until they punctured.

That happened with the front one last week. I was pumping it up before a ride and the tube blew. I discovered that the valve base had separated from the tube (a cheap Cheng Shin rather than the Continental I had expected to find).

So now I have one threaded and one smooth on the Scott but as I'm still a cheapskate I'll wait for the rear tube to puncture before changing it to a decent Michelin Aircomp!

[asad137]

On a regular road tire, smooth valve stems are fine. But I have a set of studded winter tires with a very thick, stiff casing. Using a threaded stem with a nut means I can put the pump head on the valve stem on a fully deflated tire without pushing the whole stem into the rim.

Asad

[Pirx]

The threaded ones suck.

You could have stopped right there.

The knurled nut is supposed to keep the valve stem in place better.

Knurled nuts are for Freds. Don't be caught having one of those on your rims...

[Pirx]

+1 if you have tires that take higher pressures like Vreds, you really want the threaded stems. They stop the pump from "blowing off".

Uhmm, in all of my now roughly 30 years of cycling, I have never, ever, had a pump "blow off".

As mentioned above, the threads make it less likely the pump head will blow off the stem...a situation that invariably puts my as yet unshod tootsies in danger.

See above. My tootsies are just fine. In fact, before I read this thread, it had never occurred to me that they might be in any danger.

When the tube is entirely deflated, it is much easier to get the pump head onto the stem when the stem fastened down.

Yep, really hard to push that stem down by pressing with your thumb on the tire.

At any rate, yes, I'm clumsy.

So it would appear.

[ddimick]

Knurled nuts are for Freds. Don't be caught having one of those on your rims...

Unless you're running tubeless, in which case they are mandatory.

[stephen9666]

I like the threaded stems in wheels that originally had schrader valve tubes. It keeps the stem from moving around so much in the larger rim hole.