Does the thumping go away after a few miles? If not it's likely not a tire. Bias ply tires flat spot when they sit leading to a thumping ride on cold start. As the tires warm up the flat spot goes away.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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