|
Yes it is adjustable and BMW's typically tell you that you are running a few miles faster than you actually are (could help save you a few speeding tickets)
As far as your tire size... 225/50Z16's, are the same size as 225/50R16's
Width/Ratio/SpeedRating/RimSize.
TireRack.com can explain the numbers more effectively. The R tires aren't rated to go as fast as the Z but they will last longer.
__________________
|