Has something changed in tyre valves?

[GideonReade]

I've had a number of occurrences in the last couple of years where, on preparing to add some air to a tyre, the Presta valve core has come loose. Sometimes just a gentle hiss hastily tightened, sometimes rather more rapidly emptying the tyre, and once shooting the valve core clean out of sight.

But only in the last few years.

Is this because I've started using Schwalbe tubes, or has something changed, or have I just forgotten an age old problem?

(Presta, 700c, usually about 60psi max. To peak Road Morph.)

[Brucey]

both Continental and Schwalbe use screw-in inserts for presta tubes (not all makers do). What has changed is that they don't always tighten them properly in the factory. It is a good idea to tighten them properly (eg with a small spanner) when you first fit the tubes.

cheers

[landsurfer]

Vittoria tubes are often available from Planet X for £9.99 for 10 .... and they are faultless.
Buy some.

[reohn2]

Vittoria tubes are often available from Planet X for £9.99 for 10 .... and they are faultless.
Buy some.

Yes good tubes but P X only sell limited sizes.

Once the valve core is tightened up in Schwalbe or Conti tubes they're faultless tubes too,been using Schwalbes for donkeys and the odd Conti tube without problem.

[landsurfer]

Yes good tubes but P X only sell limited sizes.

Once the valve core is tightened up in Schwalbe or Conti tubes they're faultless tubes too,been using Schwalbes for donkeys and the odd Conti tube without problem.

Good point, well made ...

[Roadster]

The connectors on Lezyne mini-pumps are notorious for unscrewing presta valve cores upon removal, causing instant deflation of the tube after one has just expended significant time and energy on pumping it up. If you've recently bought such a pump and haven't yet used it, check that your removable valve cores (if fitted) are well tight before you do. Don't ask me how I know this...!

[iandriver]

Threadlock on the valves with those pumps has been suggested before.

[rmurphy195]

I've known the valve caps to grip the valve when taking them off - the yellow ones made of softer plastic seem to do this a lot.

[CJ]

I like those screw-in valve cores. The possibility of them unscrewing is easily avoided and on the plus side:
1) Keep a few old cores from much-punctured tubes and you can repair any faulty valve.
2) If you have severe puncture problems you can thus add slime (or similar product) as easily to a presta-valve tube as to schraeder.

[ratherbeintobago]

I’ve just bought a Unior 4mm spanner for tightening valve cores...

[RickH]

The connectors on Lezyne mini-pumps are notorious for unscrewing presta valve cores upon removal, causing instant deflation of the tube after one has just expended significant time and energy on pumping it up. If you've recently bought such a pump and haven't yet used it, check that your removable valve cores (if fitted) are well tight before you do. Don't ask me how I know this...!

The newer connectors with a pressure release button (to depressurise the hose) are supposed to help stop the adapter unscrewing the core.

I've not encountered any problem with cores unscrewing using mine (but I do also habitually check the core is tight when first using a tube).

A recent foray into tubeless tyre territory means I now have a tool specifically for the job of tightening (& removing) valve cores that I've added to my on-the-road toolkit.

Valve core tool

DSC_0574_crop_219x309.JPG (51.65 KiB) Viewed 1263 times

[Brucey]

....A recent foray into tubeless tyre territory means I now have a tool specifically for the job of tightening (& removing) valve cores that I've added to my on-the-road toolkit.....

you might want to also check that you can remove the valve from the rim when the tyre is flat. Usually you can't, because the locknut is made snug when there is pressure in the tyre. You might want to carry a small pair of pliers to help you remove the valve, should you wish to fit a tube.

cheers

[RickH]

you might want to also check that you can remove the valve from the rim when the tyre is flat. Usually you can't, because the locknut is made snug when there is pressure in the tyre. You might want to carry a small pair of pliers to help you remove the valve, should you wish to fit a tube.

You're probably right but I've also got some plugs (that some folk call "anchovies"*) to stuff in holes that sealant won't fill. Maybe I'll get a tyre damaged beyond that sometime but, from my experience, a very rare occurance - I think twice in the last 10 years I've suffered any bad tyre damage/failure & the most recent of those (the previous one was 2008) was bead failure, so the spare tyre I usually carry was more use than anything else (I was running tubes in that instance & don't fit lockrings with tubes).

[Brucey]

somewhere between 1/10 and 1/4 of the punctures that I have had in recent years have gashed the tyre badly enough that a tube would have to be fitted to a tubeless tyre and a boot is needed with any tyre. It is easy enough to make the tyre rideable again with tubed tyres, rather less so with tubeless. I am not looking to change to tubeless anytime soon...

cheers

[flat tyre]

I recently had the same problem with the presta valve unscrewing when using my mini pump (topeak), twice after pumping away for a few minutes, I managed to get the tyre re inflated with CO2. I have tried putting some Loctite on the valve before reseating it when I got home, just wondering if this is going to present problems later on and if it will be sufficient to stop it unscrewing with the pump again?
I prefer to use screw in valves as I am using tubeless tyres so will need to remove the valve at some stage for sealant top up.