There's often a bit of variation in tire diameters, even within the same model range. Have you tried another identical one? Also, don't fill it all the way before going around the circumference ensuring it hasn't moved while inflating.
@withered_preacher started
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There's often a bit of variation in tire diameters, even within the same model range.
Have you tried another identical one?
Also, don't fill it all the way before going around the circumference ensuring it hasn't moved while inflating.