AMuzi wrote:

Air going in passes through the top pin hole
under the rubber tube segment and into your
inner tube. Air cannot go back out the other
direction through that hole so one must undo
teh top nut to let air escape (as you noted
in prior post).

Right, then the preassure from inside the tube
dislocates the whole thing, away from the
opening to let the air out?

But just isolating the valve, how does it (the
valve) work? The rubber is a loose lid over
a cylinder. Blow from within the little pipe,
the lid lifts just a bit to let thru air.
Blow from the outside, it stays down?

(Here the "outside" is actually the inside of
the tube.)

Is this correct?

Why does the Dunlop deteriorate? The rubber
looses its freshness/moisture to shrink and not
cover the hole? What about lubing it?

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underground experts united
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