Flat tire? Check valve stem first!

[ScottRNelson]

From the department of Duh.

I had a tire go flat on me while I was waiting for another rider, less than a mile from my home. Pumped it back up with the tire pump that I carry with me, rode it home, got a different bike, then stuck my other set of wheels on that bike, since I had planned to do that anyway. Let it sit for couple of weeks before getting around to repairing the tire.

After carefully taking the tube out then pumping it up and dipping the thing in water to see where the leak was, it was the valve stem! The guys at Cycle Gear that installed the tire a month ago didn't bother to tighten the core sufficiently. If I had bothered to check that before pulling the tube out I would be done already and not be worrying about pinching a tube - which I seem to do about half of the time.

I'll be sure to remember to check this in the future. Let this be a warning that may help one of you avoid doing something this stupid in the future.

 

[HadesOmega]

Happens to me sometimes. They get loose sometimes. I'll be walking back to my bike and flat tire. Always good to carry a pump on you or the bike and apparently a valve core tool.

Sometimes I feel like someone is playing a joke on me and loosening it. '

Sometimes the core itself could be leaking also, so those old tubes your throw away salvage the valve cores from them.

 

[dravnx]

Happens to me sometimes. They get loose sometimes. I'll be walking back to my bike and flat tire. Always good to carry a pump on you or the bike and apparently a valve core tool.

Sometimes I feel like someone is playing a joke on me and loosening it. '

Sometimes the core itself could be leaking also, so those old tubes your throw away salvage the valve cores from them.

This!

 

[anytwowilldo]

From the department of Duh.

I had a tire go flat on me while I was waiting for another rider, less than a mile from my home. Pumped it back up with the tire pump that I carry with me, rode it home, got a different bike, then stuck my other set of wheels on that bike, since I had planned to do that anyway. Let it sit for couple of weeks before getting around to repairing the tire.

After carefully taking the tube out then pumping it up and dipping the thing in water to see where the leak was, it was the valve stem! The guys at Cycle Gear that installed the tire a month ago didn't bother to tighten the core sufficiently. If I had bothered to check that before pulling the tube out I would be done already and not be worrying about pinching a tube - which I seem to do about half of the time.

I'll be sure to remember to check this in the future. Let this be a warning that may help one of you avoid doing something this stupid in the future.

I've had valve stems leak on me in the past. Specially on dirt bikes, as it is so easy to get a tiny bit of dirt down the stem. I often use my fingertip to put a bit of spit on the tip of the valve stem, to make sure I don't have a leak.

 

[DonTom]

Don't you guys use valve caps? Tire experts say they do more to hold the air in the tire than does the valve. The valve is only designed to not let the air out as you try to fill or check the tire psi. IOW, the valve is for temporary stuff. Should always use a valve cap.

-Don- Rainy Payson, AZ (RV)

 

[ScottRNelson]

Don't you guys use valve caps? Tire experts say they do more to hold the air in the tire than does the valve. The valve is only designed to not let the air out as you try to fill or check the tire psi. IOW, the valve is for temporary stuff. Should always use a valve cap.

Of course there was a valve cap on there. But it was the original plastic one that came with the tube.

What kind of valve caps will hold in the pressure, say, without a valve core installed? I don't think any cap I've ever seen could do that.

 

[DonTom]

What kind of valve caps will hold in the pressure, say, without a valve core installed? I don't think any cap I've ever seen could do that.

I think you will be surprised, as long as it's not a cheap Chinese plastic cap but a metal one with the gasket.

This RV has all the tires filled to 80 PSI. I have external TPMS sensors on each tire, that keeps the valve open at all times. They have been on for years with no problems.

I also use such on all my motorcycles. Never a problem. All the valves are pressed in open at all times.

-Don- in rainy Payson, AZ (RV).

 

[sprorchid]

Yeah, I thought my 1 ish psi per day rear tire leak was a bead leak, then I thought it was the valve stem core, but it's actually the rubber in the angle valve stem itself. I'm too lazy to take the whole tire off just to swap that out.

 

[Tom G]

Can't you just push one side in using your machine and then replace the valve? I would think you have fairly wide rear rims on the back wheel. Just my 2c.

 

[CDONA]

Yeah, I thought my 1 ish psi per day rear tire leak was a bead leak, then I thought it was the valve stem core, but it's actually the rubber in the angle valve stem itself. I'm too lazy to take the whole tire off just to swap that out.

I believe this is the cause of air loss on my new Monkey, I have to top off every week. Angled valve stem is very flexy, and cheap, not screwed down like the angled stems on my old hyper.

Two years ago my TW200 front started flatting every day or two, I tried swapping valve cores, sometimes it would last a week, then flat.
I thought someone in camp was "giving me the business".
I would even try indexing the stem when parked overnite, up or down, easy to get to under the cover or hard, pull the cover for access.
I had to swap tubes to fix.
No holes/leaks with submerged tube in a bucket of water.
No thorns, glass or nails in tire, metal valve cap with gasket.