What tires are you using and what kind of mileage are you getting.
I got 14,000 out of my original Metzler MZ4 but I may have been pushing the envelope. I'm going to replace mine before track day on May 9 because they won't pass inspection. I was planning on ordering a set of Metzler ST6? but another RT rider I know just bought Michelin Pilots because they are supposed to get better mileage.