Answer:
It depends on how deeply we look at it:
The simplest answer is countless, because a bicycle tire has circle shape.
The more full answer is quite complicated, as a bicycle tire consists of three basic elements: the carcass, the bead core and the rubber tread. If you see in the first picture (attached below) - case (a) has the answer "countless", while case (b) has the answer "8", and the last case (with a real bicycle tire has the answer "none" because of the complicated red pattern and other details on it. As for the second picture, because of the word "Gipsy", you can not define any symmetry line too!
Explanation:
This is very very interesting question!
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