Lets face it the tyre on your bike makes the primal decision for the rest of the system both where the airflow is going to go and your connection with the road when zipp introduced the tangente line of tires in 2007 they focused on leading edge airflow properties and how they interfaced with the rims zipp worked with an industry leading manufacturer to develop the tire casing and tread compound but did not have as heavy of a focus on rolling resistance for the redesign of tangente tires