To find tire size, check your owner’s manual, the driver’s side door jamb, and the side of the tires for a series of letters and numbers. The two numbers off R will indicate your rim size.
For example, if the tire size is P225/45R17, the rim size is 17 inches. Rims for BMWs can be pricey, so you may want to shop around before committing to a particular set.
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