What eco friendly chemicals can be used to soften auto racing tires?

[pkkart]

What eco friendly chemicals can be used to soften auto racing tires?

 

[Metten]

You cannot soften rubber after production/vulcanisation without affecting the characteristics of the tire.
Several solvents will make the tires swell and make them softer, but you actually need another rubber formulation.

 

[GrahamBennett]

Metten is 100% correct.