I assume aerodynamics weren´t made for Mach 2 as the B-1B is relatively slow (around Mach 1.3) ?
The original B-1A was a true Mach 2+ airplane at altitude. The B-1B has been slowed down quite a bit due to design and mission mods, but still retains most of the high-speed aerodynamics of the earlier model:
1) The variable engine inlets (the real key to Mach 1.5+) were replaced with simpler fixed inlets to reduce cost;
2) There was significant structural beef-up to allow the airframe to perform low-level penetration missions, quite a change from the high-level mission originally intended, as well as a much larger on-board electronics suite for self-defense. MTOW went up from about 350,000-375,000 lbs. to over 477,000 lbs., without any increase in thrust, so performance suffered accordingly;
3) As the mission was changed from high-altitude to low altitude, max speed also dropped with the increase in air density at low level.
It would be interesting to see a B-1R, but I really doubt if one would ever be built.