Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
The 285 dimension isn't really the part that affects odo/speedo or revs. It's not the width but the height of the tire that will affect it.
Actually I'm a little bit wrong here. If you have a 275/65/18 and a 285/65/18 you'd think by looking at the size that they had the same diameter, and just the width was different. However the 285/65/18 is a 1/2 in taller, I'm not sure how this sizing system came about.
'65' in your examples is the "aspect ratio" The tire has a sidewall height that is theoretically 65% of the tread width (so 285mm*0.65= 185.25mm sidewall height).