I was talking about the full length ones when inverted, so the long part of the valve stem is on the inside of the rim acting as a plug for the original hole in the outside of the rim (which is now the inside when flipped).
If the original valve stem is on the inside of the tire when the tire goes flat, wouldn't the weight of the machine decompress the tire to the point where the original full length valve stem will push against the ground/inside of the tire when it rolls past that part of the rim?
I'm not sure if it would, it's just something that popped into my head, considering the length of the factory valvestems are like 1- 1 1/2'' long.
~Bill