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Tire speed ratings do not apply to repaired or modified tires. The original rating is done to an intact tire and does not reflect the performance of a compromised tire. Opinions vary, but you can probably only safely get 75 to 80mph out of a patched tire. Those who routinely push the speed limit should replace punctured or damaged tires, not repair them. Don't forget that the speed rating of your damaged tire goes down further with heat, low pressure, and other factors. Tire speed ratings are assigned in optimal conditions, there is no official data as to how tires perform when the structure is damaged, patched, and put back into service.