What is the biggest size of rims you can put on a BMW 645?

The BMW 645 typically accommodates rim sizes ranging from 18 to 20 inches. Some enthusiasts may opt for larger rims, such as 21 inches, but this can affect ride quality and handling. It's essential to consider factors like tire size, offset, and clearance to ensure the rims fit properly without causing rubbing issues. Always consult with a professional or refer to manufacturer guidelines before making modifications.