Losing tire pressure

[Ramie]

I've noticed that I loose about 5 to 6 psi in my rear tire every week (Avon Cobra).  I suspect the rear valve but I seem to recall someone posting about pin hole leaks in one of their Avon tires and was just wondering if this was a problem with some tires.  I purchased 90 deg valve's with the nut on top, I think the current valves have a nut on the inside but I can tell as there seems to be some type of plastic support covering the base of the valve.

[sandy]

The plastic support is probably an original pressed in stem. I've run several sets of Avons with no air loss issues. Spray some soapy water at the stem and wiggle it around. You might find the problem.

[salty1]

 

The plastic support is probably an original pressed in stem. I've run several sets of Avons with no air loss issues. Spray some soapy water at the stem and wiggle it around. You might find the problem.

:cooldude:Also check the bead of the tire for any leak and that the bead is fully seated.

[Cliff]

had a similar problem on the front.  Finally decided to put the tire/rim in water to look for bubbles, since it was a slow leak I decided to raise the pressure first so that there would be more bubbles coming from the slow leak source,  pressure up to 50psi, no leaks found in the water,,,,,,,,,  gave up, dropped the pressure back to normal,,, presto change-o  no more slow leak. 

Suspicion is it was leaking somewhere around the bead edge and increasing the pressure forced a better seating of the bead.  The slow leak never returned for the life of the tire.