>I am wondering, what is the official way to measure
>the tire width?
>
>There is a large variation it seems with makers, and I
>am wondering what the right or various methods are.
>
>Is it simply the width (L-R) at the widest point
>measured with a caliper?
That is how I measure it. Make sure that you don't compress the tire. I start too wide, and close the caliper in 0.5 mm steps. When the caliper can't wiggle any longer, you have the width.
However, tire width depends greatly on the rim. The Grand Bois 700 x 30 mm measure 31 mm on my Mavic MA-2 rim (20 mm wide), but 34 mm on a Velocity Synergy rim (24 mm wide).
So which size is correct?
Jan Heine
Editor
Bicycle Quarterly
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