OT Mark, but why are you not going with the 335s again? Too much difference between those and the fronts? What fronts are you using now, I know you were trying the larger 305s for a while.

 

the 335s pinched the tire enough that the tread width was near the same as the 305, but it had more rounded edges so there probably was even less contact patch . I also felt that the shorter sidewall made it a little looser even with lower pressures. The fit was so tight that I did have some very slight rubbing, but I would deal with that if the tire was actually wider they are heavier too.

I have raced with the 305s up front. there are some subtle trade offs vs the 275s, as the right hight went up 1/2 " and the tires are near 4lbs heavier per tire.

mk