A couple of years ago, I was given a BMW 5 Series to test. The ride along the overhead expressway was excruciating. Thump, thump, thump on every break in the concrete, so I was interested to read an Australian tester who had written, “Looking for any surface resembling Australian roads, our test cars (X3’s) coped well through a rough patch of road works despite running on 18-inch alloys and lower-profile, run-flat tyres.
According to BMW Group’s chief assessor of driving dynamics Heinz Krusche, the company has been working closely with its five run-flat tyre suppliers to reduce the side-wall stiffness for improved comfort. As a result, deflated travel distance has been reduced from 150 km to 80 km, which BMW stresses are conservative recommendations.”
About time, Herr BMW. About time!