It really depends on how you ride up there. I get 1 trackday out of a set of Pirelli Super Corsas or Michelin Pilot Race. I'd imagine that you'd be able to get 2-4 trackdays out of a set of Pilot Powers, if you dont crash on them first. But again, it all depends on how you ride.
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Do you really have to start a thread every time you go on a ride and see a guy with no helmet on?
Does it affect you that much that some random guy 1500 miles away went and paid his own money for a 1000?
Do we really have to fight over who uses the back brake or not?
Do you have to argue over stupid pointless shit on the Internet?