The first number is section width (not tread width), meaning a 225mm tire is 8.85" wide - 225 divided by 25.4 = 8.85". The 45 is the aspect ratio, meaning the tire sidewall is 45% of the section width. Generally speaking, a 225/45 tire should have a 3.98" sidewall (from the very bottom edge that sits, unseen, inside your wheel). If you take 3.98 + 3.98 +17, you'll have the tire's overall diameter = 24.96".
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.