Hoosier is not happy with the performance of their DOT A3S04's and R3S04's.
They are working on an "S05" replacement.
Hopefully they will be out before April 30th.
The most recent S04 and Kuhmo's V710 were forced by the new (late 2003) DOT regs that specified better puncture resistance for street tires. This mandated steel belts rather than the fibergalss, nylon and Aramid belts used in the V700 and S03's.
My personal opinion is that steel belts don't belong in race tires as they deter heat dissipation and actually increase heat retention and heat generation by the need of running higher pressures. Plus the just make the tires needlessly heavier. But this is a Catch 22 type Reg as the DoT could care less about race tire construction and they are only made to the DOT specs as the sanctioning bodies use it to limit true R tire usage in stock classes.
It appears now that when Kuhmo's first batch started falling apart and the needed to ReCall them they also changed to a softer compound. The V700 were 45-50 and the newer V710's are 35. Hoosier kept their A's at 40 and R's at 30 but found that inorder to get even wear and avoid premature tread edge wear & belt failure they needed to run higher pressures (+45 cold)....which reduced grip. I would assume that besides some construction chages that Hoosier will also drop the compound hardness.
I also know that Goodyear is working on new DOT A and R tires.
Should be interesting.
They are working on an "S05" replacement.
Hopefully they will be out before April 30th.
The most recent S04 and Kuhmo's V710 were forced by the new (late 2003) DOT regs that specified better puncture resistance for street tires. This mandated steel belts rather than the fibergalss, nylon and Aramid belts used in the V700 and S03's.
My personal opinion is that steel belts don't belong in race tires as they deter heat dissipation and actually increase heat retention and heat generation by the need of running higher pressures. Plus the just make the tires needlessly heavier. But this is a Catch 22 type Reg as the DoT could care less about race tire construction and they are only made to the DOT specs as the sanctioning bodies use it to limit true R tire usage in stock classes.
It appears now that when Kuhmo's first batch started falling apart and the needed to ReCall them they also changed to a softer compound. The V700 were 45-50 and the newer V710's are 35. Hoosier kept their A's at 40 and R's at 30 but found that inorder to get even wear and avoid premature tread edge wear & belt failure they needed to run higher pressures (+45 cold)....which reduced grip. I would assume that besides some construction chages that Hoosier will also drop the compound hardness.
I also know that Goodyear is working on new DOT A and R tires.
Should be interesting.
