Update: I swapped the front wheels and runflat tires with 2 from a set I have in storage. The tires on that set are fairly new, non-runflat summer tires. They were mounted and balanced on to repaired M68 wheels (bent rim from a pothole), then put directly into storage about 3 months ago.
The vibration between 60-70mph is 90% gone, but I am still getting some intermittent mild vibration at around 70-75mph.
BMW CCA member - Peachtree Chapter