I have been around tires and mounting them for years...basically if the puncture is less than an inch or two from the sidewall, the tire should not be repaired...even using the patch-plug method which is considered the most effective. reason is that near the sidewall is a constant flex point of the tire, so many repair attempts fail...plugs work themselves out, patches bend back and forth and crack...etc. Also, for each time a tire is repaired assuming it is done properly and in an eligible area of the tire, that tire loses one speed rating. never should exceed 3 repairs on one single tire and none should be within 10-12 inches of the other.
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