Conventional sipes are wide at the top, narrow at the base
and decrease in size as the tread wears down, sacrificing
wet performance with tire wear. Thus, as a conventional tire
wears, it loses its tread pattern and looks more and more
like a racing slick. Wet performance suffers, because
shallower, worn tread channels lose the ability to evacuate
water efficiently. This means more water comes between the
tire and the road, resulting in ess actual contact and
reducing wet traction and handling.
Bridgestone/Firestone's Key Hole Sipe is a tread pattern
feature that helps solve these problems. A Key Hole Sipe is
a slot with a cylindrical channel at the base. In a cross
section of the tire tread, this slot-and-channel
configuration resembles a key hole. As the tread wears, the
"key holes" emerge to help ensure a consistent tread
pattern. These sipes help maintain continued wet performance
and new tire appearance.
