Too many variables to compute.....rake, trail ,wheelbase, standover, stiffness, deflection, carbon layup....
so all I can say is this - 453.6 grams per pound. You need to drop 1451.5 grams. That is probably the same weight or more as your current Roubaix RC frame.
Unfortunately since none of us have ridden the RS2 yet, its tough to say how it is to remotely give an impression compared to a carbon-stayed aluminum frame.