How is tyre width measured?

I know that a tyres width is taken from the tyre section (that is the tyre wall not the tread) the problem is how do you get an accurate size when most tyres have rim protection and different makers have more or less rubber sticking out at the side. Pirelli for instance has a huge rim protector so if you measure its section you may have a 265mm tyre but measures 285mm at the tyre wall?

Asked on 10 May 2024 by robert battley

Answered by David Ross
A tyre's width is measured in millimeters from the tyre's inner sidewall to its outer sidewall, so the presence or otherwise of a rim protector does not affect this measurement.
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