I've used acetone for many years to save rims.. most foams if not already messed up before soaking do ok. They balloon up at first.. make sure you squeeze all the acetone out and let them air dry outside. They will shrink back to normal size and will actually be a little firmer than they were originally.
Mostly I use this method for the rims only.. I cut the tires off leaving just a band around the rim beads... soak them for a few days in a sealed paint can of acetone and the bands just pull right off...
Be careful though, acetone is very flammable! Actually it can "Flash" from many many feet away if a flame source is present. So know what you are doing first!
Our hobby is very expensive.. so ya wheels may only cost $5-$8.. but if you race a lot it does add up. I usually can get 3-4 times of use from a rim before it is ugly or to used to save... so that is $15-$32.. that's a set of tires or two!
Jerome
