Today for me after about 5 laps straight i was at about 270 also. I am using OD97t, 30% byrons. When i finish and let her cool down she still feels tight so I guess its fine. I think my problem is that i am on a 13t clutchbell(all I had) So i may be over revving her on the 150 ft straight. I got a 16t and 17t on the way.