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Tire randomly loses all air
- Thread starter Boostin
- Start date
If you are sure there are no holes or leaks around the rim, check for a leaky valve stem.
Yeah, I would expect them to help you out. It wouldn't hurt to see if you can find the leak first though, in case they decide there's no problem
I would get that fixed ASAP. If it happens in a corner, you will be in trouble. My initial though for random rapid deflation while riding would be an improperly seated bead and the tire burps when you hit the wrong bump. Second thought would be a cracked valve stem that occasionally opens.
Another vote here for letting RC have a look at it. It has happened enough that the cause should be easy to find.
Another vote here for letting RC have a look at it. It has happened enough that the cause should be easy to find.
Because I avoid them at all costs but I just dropped it off. I did the soap, they did the soap, another shop did the soap, no leaks from stem tire or rim. Even three it in my pool. Nearly high sided getting off 407 this morning cause it lost all air. Il update with the cause if they find it.
Soooo..maybe stop riding it (or at least highway speeds) so you don't have an accident?
centrifugal force on the valve stem, tire spins up fast, valve stem opens against the spring by means of it's own inertia.
Valve stems open the other way, by pushing in. Centrifugal force causes them to seal harder, not open.
That's for easier inflation, especially in rims with spokes or tight metal designs. For example, on the rear tire of my VTX a straight valve stem would be extremely difficult to reach due to the spokes. With a 90 degree valve stem it's WAY easier.
Think that one through again PP. The mass of the stem is trying to fly out towards the tire thus opening. I've never heard of it actually happening though. Given the spring pressure and air pressure pushing it towards the hub and tiny mass, I would be amazed if it was possible.
No, they open by pushing in, not pulling out. If you look at an air chuck used to fill a tire there's a pin in the centre of it that pushes on the opposing pin in the valve stem - when the two meet and force is applied, that's what actually opens the stem to accept air.
Want to deflate a tire? Push the pin in the valve stem inwards, air releases. You can pull on that pin all you want (the same as centrifugal force applies) and it just seals harder.
Edit: Disregard my post, I'm thinking backwards.
Want to deflate a tire? Push the pin in the valve stem inwards, air releases. You can pull on that pin all you want (the same as centrifugal force applies) and it just seals harder.
Edit: Disregard my post, I'm thinking backwards.
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You have the action correct, but your forces backwards. The faster the wheel spins, the more the valve core wants to fly towards the outside and therefore open. I still think this is a theoretical exercise unless you are trying to set land speed records.
Edit: Disregard my post, I'm thinking backwards. Crow is tasty today.
Nope, sorry, it's you that's thinking in reverse. A valve stem points outwards, centrifugal force adds outwards force. The valve stem pin requires inward force (opposite the centrifugal force) to open the valve.
The faster the vehicle goes, the tighter the valve stem seals.
Yes, the valve assembly is being pulled outwards, but remember, the assembly itself is not what physically opens to allow the air, it's an internal mechanism inside it again (that being the valve part of the valve stem) that again, and that's designed to tighten with centrifugal force, not open. The assembly is threaded into the stem and if there's a failure or problem there (bad seal on the valve assembly, or bad face on the stem where it seats) that would indeed cause a leak, but it wouldn't be sudden like that, it would be constant.
Op needs to do a soap test on the entire tire, rim, valve etc etc and find out where the leak originates, as others have suggested.
Nope, sorry, it's you that's thinking in reverse. A valve stem points outwards, centrifugal force adds outwards force. The valve stem pin requires inward force (opposite the centrifugal force) to open the valve.
The faster the vehicle goes, the tighter the valve stem seals.
Yes, the valve assembly is being pulled outwards, but remember, the assembly itself is not what physically opens to allow the air, it's an internal mechanism inside it again (that being the valve part of the valve stem) that again, and that's designed to tighten with centrifugal force, not open. The assembly is threaded into the stem and if there's a failure or problem there (bad seal on the valve assembly, or bad face on the stem where it seats) that would indeed cause a leak, but it wouldn't be sudden like that, it would be constant.
Op needs to do a soap test on the entire tire, rim, valve etc etc and find out where the leak originates, as others have suggested.
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Edit: I'm a dumbass, nevermind.
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You know what, I need to eat crow on this one, sorry. I'm visualizing how the valve stems rest on the heavy equipment I drive and indeed the stems usually sit inline with the rim on a MC. You're right.
OP, what you may have here is a failed valve stem. Go back to the tire shop that did the work and tell them what's happening - chances are they'll just replace the valve and the issue will resolve.
OP, what you may have here is a failed valve stem. Go back to the tire shop that did the work and tell them what's happening - chances are they'll just replace the valve and the issue will resolve.
NGL I was starting to feel kinda stupid there
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