use the sponge for soldering job...wet them...let them dry completely...soak in some liquid which people use to thin building decoration paint (but it is not thinner...i am not exactly sure about the english name but i will try to find it out later), spin you tires on tire truer and rub the spone against the tire like you are sanding your tires with sand paper.....
the tires will get some clean and grippy...like when they are just out of box...and in fact you will smell the same smell....
