For street tires you do not need heat cycles.
But for DOT R tires it is recommended. When you heat cycle a tire you have to run it at a certain temperature range for 15-20 minutes. When you do a heat cycle it realigns the bonds in the rubber making them more sticky and last longer. I forget the exact science behind it, but it's sort of like magnatizing metal when you rub another magnet on it.
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