I am in desperate need to replace the rear meats on my SPD Tricub. The originals are one-piece balloons with no size imprinted. I have inflated these to recommended circumference and measure OD at 18½” and width at 10¾-11”. I am trying to size a tire/wheel to match these dimensions as close as possible. I’m looking at various tires 18x10-8 to 20x11-8 (rim diameter is immaterial at this point). I have also physically measured several ATV-type tires and get various results compared to the imprinted size… i.e. 22x8-10 = actual 20¼” x 9”and 24x11-10 = actual 22½” x 12”.
It there a way to predict actual physical dimensions based on the specified size? I know that the rim width can affect the size to some degree. I'm trying to avoid ordering something and be too far off on the size. Any advice appreciated.