2018 BMW 430i — Coupe M Sport

The 2018 BMW 430i Coupe M Sport shipped with 3 different factory tire sizes, depending on the wheel package it left the factory with (this can also reflect a staggered front/rear setup). Check your tire sidewall or door placard to confirm which one applies to your vehicle.

This trim shipped with more than one tire size (staggered fitment, front/rear, or optional wheel package). Confirm which one matches your vehicle by checking your tire sidewall or door placard.

225/45R18

Section width225 mm
Aspect ratio (sidewall height)45% (101.3 mm)
Rim diameter18"
Overall tire diameter~26"
Revolutions per mile~777

Compare prices at:

225/45R18 (front)255/40R18 (rear)

Compare prices at:

225/40R19 (front)255/35R19 (rear)

Compare prices at:

Other 2018 BMW 430i trims

How to read a tire size

A tire size like 225/45R17 breaks down into three parts: the first number is the section width in millimeters (the tire's width from sidewall to sidewall), the second is the aspect ratio — the sidewall's height as a percentage of that width — and the number after the "R" is the rim diameter in inches. A letter prefix (P or LT) indicates Passenger or Light Truck construction; its absence usually means Euro-metric sizing.

Some trucks and off-road tires instead use "flotation" sizing, like 37X12.50R17 — here the numbers are the tire's overall diameter and width in inches directly, with the rim diameter last.

Always verify against the tire information placard on your driver's-side door jamb or your owner's manual before purchasing — tire size can vary by factory option package even within the same trim.