nut on a Presta valve - yes or no?

[kylecycler]

Might be an idea to put a drop of lube on the threads, I've never thought to do so, but just make sure it's not enough for the lube to seep as far as the rim. Wouldn't make any difference if the cold causes it to stick, though. Suppose if you can't unscrew the nut you'd have the alternative of leaving the valve in the rim and just pulling the tube out and repairing it (but maybe not in December, in the rain or snow!).

[Percy]

They seem pointless to me - if the tube's pumped up, the valve doesn't move; if you get a flat you stop and fix it, so I don't see the point of them - but have I over-looked something?

I pumped up the tires on my fat bike, one evening. The next morning one of the tires was flat. At first I thought it was a puncture but it turned out to be that I had forgotten to tighten the nut. I guess the plastic cap must have pressed on the pin and let the air out. I know some cyclists throw the caps away but in my mind, that exposes the valve to dirt which then has to be thoroughly cleaned off before attaching a pump.

[MartinC]

It's not corrosion etc. It's temperature.........

Wow! Every day's a school day. It's always amazing how diverse our riding experiences are. Is it the contraction or frozen moisture? I guess the solution is the time immemorial one of using your bodily supply of warm water! Leaving it off but always keeping the one on the spare tube you're carrying would solve the pump problem when needed.

[kylecycler]

I know some cyclists throw the caps away but in my mind, that exposes the valve to dirt which then has to be thoroughly cleaned off before attaching a pump.

I think I'm right in saying that a lot of us on the forum don't ride in the mucky stuff so we never think about our valves getting clogged with dirt!

As for the 'dust cap' also being to prevent abrasion from the edge of the valve when the tube is in storage, that might explain why Schwalbe valve caps are smooth and rounded, with no sharp outside edges (even though they're plastic, of course).

[kylecycler]

It's not corrosion etc. It's temperature.........

Wow! Every day's a school day. It's always amazing how diverse our riding experiences are. Is it the contraction or frozen moisture? I guess the solution is the time immemorial one of using your bodily supply of warm water!

Oh, please! But yeah, you're right, whatever it takes!

Many's the time I've held a jar under a hot tap to free the lid. Rubber gloves also help with that, and many of us carry disposable rubber gloves on the bike, so I suppose they might help too (especially if you've peed on the valve first!).

[nez]

It's not corrosion etc. It's temperature.........

Wow! Every day's a school day. It's always amazing how diverse our riding experiences are. Is it the contraction or frozen moisture? I guess the solution is the time immemorial one of using your bodily supply of warm water! Leaving it off but always keeping the one on the spare tube you're carrying would solve the pump problem when needed.

I don't know Martin. But twice in my years of riding I have had these little so-and-sos refuse to move even with a gloved hand - you just take the skin off a bare hand. Once off they are not corroded nor were they put on with excess force and I can't help but notice it was freezing and dark when the refusal happened. Eventually you get them off but it's only after a lot of swearing and (once) as you suggest, pee-ing. It would turn a man to Marathon Plus. Luckily I don't commute any more.

[nez]

It's not corrosion etc. It's temperature.........

Wow! Every day's a school day. It's always amazing how diverse our riding experiences are. Is it the contraction or frozen moisture? I guess the solution is the time immemorial one of using your bodily supply of warm water!

Oh, please! But yeah, you're right, whatever it takes!

Many's the time I've held a jar under a hot tap to free the lid. Rubber gloves also help with that, and many of us carry disposable rubber gloves on the bike, so I suppose they might help too (especially if you've peed on the valve first!).

You're right. I carry disposable gloves now. You get the same issue with camera filters on lenses. You can remove these using a rubber band band but they don't make inch wincy rubber bands for tyre tube locknuts.

Maybe a tiny smidge of copper grease might do? Dunno.

[Marcus Aurelius]

I believe that the presence of the nut is actually to do with shipping and packaging regulations, and has no valid technical reason for being there ( unless it’s on a tubeless set up, where there is good reason for it) Personally, where I’m using presta valved tubes, I just use a little square of gaffer tape to stop any rattling issues.

[simonineaston]

It's great to hear all the points of view! I'm gonna carry on not bothering with the circular metal threaded nut but deffo keep using the plastic valve cover. I'd forgotten too that Michelin's Presta valves are smooth, and thus could help the longevity of my track pump head rubber washer

[kylecycler]

Here's what Schwalbe says:

The rim nut fixes the valve in the rim. Some regard it as unnecessary. And indeed, you may well ride your bicycle without a rim nut. It is however helpful when attaching the pump connector, as particularly when the pressure is low the valve may fall inside the rim. With some rims there may be a rattle if the valve is not fixed.

The rim nut must only be tightened by hand. Never tighten the rim nut with pliers, as this can lead to tube damage.

https://www.schwalbe.com/en/ventile

[freiston]

I voted option 1 but I wouldn't word it as strongly as "Wouldn't go without them".

Other posters have said what kylecycler's Schwalbe quote nicely sums up and I concur.

Here's what Schwalbe says:

The rim nut fixes the valve in the rim. Some regard it as unnecessary. And indeed, you may well ride your bicycle without a rim nut. It is however helpful when attaching the pump connector, as particularly when the pressure is low the valve may fall inside the rim. With some rims there may be a rattle if the valve is not fixed.

The rim nut must only be tightened by hand. Never tighten the rim nut with pliers, as this can lead to tube damage.

https://www.schwalbe.com/en/ventile

[mcshroom]

I've found that when using a Continental tube's metal nut upside down, the smooth shoulder on the nut sits in a Schrader valve hole snugly and holds a Presta valve steady.

[ANTONISH]

What tatanab said.
Also I've come across newbies struggling to get a tyre on a rim where they have tightened up the nut before trying to fit the tyre.

[Hellhound]

They seem pointless to me - if the tube's pumped up, the valve doesn't move; if you get a flat you stop and fix it, so I don't see the point of them - but have I over-looked something?

I pumped up the tires on my fat bike, one evening. The next morning one of the tires was flat. At first I thought it was a puncture but it turned out to be that I had forgotten to tighten the nut. I guess the plastic cap must have pressed on the pin and let the air out. I know some cyclists throw the caps away but in my mind, that exposes the valve to dirt which then has to be thoroughly cleaned off before attaching a pump.

You are describing the core-valve.
We are(I think) talking about the collar that secures(?) the valve stem to the rim.

[kylecycler]

What tatanab said.
Also I've come across newbies struggling to get a tyre on a rim where they have tightened up the nut before trying to fit the tyre.

And that could cause a pinch puncture at the valve, couldn't it? I'd forgotten this but I always back the nut right off and push the valve up into the tyre to make sure the tube isn't trapped before I screw it back down again.