Why do my inner tubes keep developing leaks through the valve?

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Airlane1979
Posts: 4
Joined: 27 Sep 2021, 11:17am

Why do my inner tubes keep developing leaks through the valve?

Post by Airlane1979 »

Twice in the last week my inner tubes have leaked through the Schrader valve. In the latest one, it was a brand-new tube that I took out and within a couple of hours punctured on the road. At home, I fixed the leak, tested the tube, then deflated it and replaced it inside the tyre. On refitting it to the bike, I began inflating it but after a few seconds it lost all its air through the valve. Why would this be? How can I stop it happening? I'm buying too many new tubes.
axel_knutt
Posts: 1692
Joined: 11 Jan 2007, 12:20pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by axel_knutt »

Are you using dust caps? Is there grit getting in? Are the valve cores coming loose?
“I'm not upset that you lied to me, I'm upset that from now on I can't believe you.”
― Friedrich Nietzsche
Jdsk
Posts: 11131
Joined: 5 Mar 2019, 5:42pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Jdsk »

Welcome.

Are you an experienced cyclist and tyre fixer or have you started recently, please?

Thanks

Jonathan
Valbrona
Posts: 2498
Joined: 7 Feb 2011, 4:49pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Valbrona »

Leaking from the valve, or is the tube splitting where it joins to the valve stem? if it is the latter there may be sharp edges to the hole in the rim that is puncturing the tube.
I should coco.
Airlane1979
Posts: 4
Joined: 27 Sep 2021, 11:17am

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Airlane1979 »

axel_knutt wrote: 27 Sep 2021, 1:54pm Are you using dust caps? Is there grit getting in? Are the valve cores coming loose?
Yes, dust caps. The cores look tight.
Airlane1979
Posts: 4
Joined: 27 Sep 2021, 11:17am

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Airlane1979 »

Jdsk wrote: 27 Sep 2021, 1:57pm Welcome.

Are you an experienced cyclist and tyre fixer or have you started recently, please?

Thanks

Jonathan
I've cycled since I was 5 (I'm 55) but not long distances, just for pleasure or to get somewhere cheaply. My maintenance skills are poor no matter how I try so I need good advice from cyclists who know what they are doing.
Airlane1979
Posts: 4
Joined: 27 Sep 2021, 11:17am

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Airlane1979 »

Valbrona wrote: 27 Sep 2021, 1:59pm Leaking from the valve, or is the tube splitting where it joins to the valve stem? if it is the latter there may be sharp edges to the hole in the rim that is puncturing the tube.
Directly through the valve, no splits in the tube around the valve.
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NUKe
Posts: 4140
Joined: 23 Apr 2007, 11:07pm
Location: Suffolk

Re: Why do my inner tubes keep developing leaks through the valve?

Post by NUKe »

possible the valve its self is loose Shrader or presta? best thing is to take them our and reseat.
NUKe
_____________________________________
Jupestar
Posts: 289
Joined: 29 Feb 2020, 3:03pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Jupestar »

Try a different pump. could be damaging the valves.
Mike Sales
Posts: 6264
Joined: 7 Mar 2009, 3:31pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Mike Sales »

I take it that you have observed the bubbles leaving the valve?
A Schraeder valve core may look tight but still be leaking. Car accessory shops sell a Schraeder dust cap with a core tool, if your bike shop does not. Cheap enough and would assure the core is turned home.
A faulty valve is easily replaced.
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Mick F
Spambuster
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Location: Tamar Valley, Cornwall

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Mick F »

I have four spares for my two bikes each.
All Schrader.

If and when? I need new tubes, they WILL NOT be Schrader as I'm sick to the back teeth of the leaky valves.
Goodness knows why they have removable valve cores.

Seriously thinking of selling my brand new (still in their boxes) spare tubes and buying another make without the removable core option.
Mick F. Cornwall
simonhill
Posts: 3815
Joined: 13 Jan 2007, 11:28am
Location: Essex

Re: Why do my inner tubes keep developing leaks through the valve?

Post by simonhill »

Just to make it clear to the OP.

Are you aware that the inside of the valve is screw in? If it is loose it will leak. The dust cap/tool can be used to screw it in.

PS I have used Schrader for decades and no problems. Schwalbe tubes with steel valve stems
Mike Sales
Posts: 6264
Joined: 7 Mar 2009, 3:31pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Mike Sales »

I used to work as professional mechanic and found so often that a loose Schrader valve core was the cause of a flat tyre that it soon became the first thing I checked.
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Mick F
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Joined: 7 Jan 2007, 11:24am
Location: Tamar Valley, Cornwall

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Mick F »

Me too.
often have a flat or soft tyre after a day or three. No matter how tight I screw the damned things, they still eventually leak.

I ask again .......... why are they removable?
I won't be buying them again.
Mick F. Cornwall
Jdsk
Posts: 11131
Joined: 5 Mar 2019, 5:42pm

Re: Why do my inner tubes keep developing leaks through the valve?

Post by Jdsk »

Jupestar wrote: 27 Sep 2021, 4:44pm Try a different pump. could be damaging the valves.
Yes.

What type of pump head have you been using?

Jonathan
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