put a shock on the bike and it won't spin and I bet you will 60' better as well. I always ran untra softs at 10-12 psi. Those shinko slicks are very tempramental, I would strongly consider a power one. I was personally running 16/45 at 70" 205 suited with 1.33-1.35 60' times and using all six gears in the 1/4 and running 8.4xx at the same mph you are.