PARIS – Already delayed, the Tour de France sets off Saturday shrouded in uncertainty, flying in the face of the coronavirus pandemic and the imponderable question of how many of the 176 riders will avoid infection and endure three exceptionally tough weeks of racing to reach the finish in Paris.That's if the rolling roadshow gets that far.Staging cycling’s premier race when COVID-19 infections are rising again in France represents both a health risk and an embodiment of French President Emmanuel Macron’s insistence that the country must learn to function as normally as possible with the virus.