richardcoxid wrote:
One of my “original 5 G/Y “G” rated tires was always 10-15# low on pressure. I must have had the tire and rim “dunked” 5-6 times with NO bubbles visible. One tire shop finally dis-mounted the tire and on removal of the metal stem found that the molded seal had been installed at an angle and pinched between the rim and the stem. They said that when the tire wasn’t rotating it would seal OK, when the tire was rotating there just enough “rim flex” even though it would only flex a few thousandths of an inch it would squeak out a small amount of air every rotation. They installed a new metal stem and seal and the air loss went to “zero”.
Excellent investigative work!