Stoner's Tarminator. Yes, it's bug and tar remover, but whatever is in it sinks into the rubber and actually removes EVERYTHING from the rubber. Including mold release and the lubricant the tire shop uses to mount the tire. This is especially important on Michelin tires as they are hard to get clean enough to accept a tire product, and that's what you want, for a product to actually sink into the rubber rather than float on top. I've used many other "rubber cleaners" and nothing works as good as this.