Molded Tyre inserts-yay or nay?

[BrianG]

If they are denser, it would make sense that the tires would balloon less. For a tire to expand outwards, the sides have to come in (tire gets narrower). So, if the foam helps the tire stay at its designed width, the tire can't expand since it can't get narrower. Of course, you'll still have some ballooning, just not as much. Those molded inserts would probably make it easier to put together a tire that is balanced better too since it's not as squishy as regular foam.