I was having the same problem at 35 to 40 MPH. I found that my tires were under inflated sightly. In order to increase the mileage I have been running 50 Pounds of pressure in the front and rear. I run the ME880 Metzlers and can average 20,000 miles on the back tire and not give up any performance in the curves. As a matter of fact I am dragging my rider pegs in the curves. I have run Bridgestone and Dunlop tire too. I feel the Metzlers out perform any other tire I have used.