Originally Posted by grampi
Originally Posted by BMWTurboDzl
Originally Posted by grampi
I don't get it. There isn't more rubber on the larger diameter wheel size tires, in fact there's less rubber because they have shorter sidewalls. Is it more costly to manufacture tires with a larger diameter hole in the middle? Makes no sense...
Why would you think there's less rubber? It's fairly obvious the larger tires require more material just by the weight difference. Demand also impacts cost. Unique tire sizes have limited demand which drives up cost per unit. A unique size can be large or small vs the population.
PS A/S 3+:
245/45R20 - 30 lbs
245/45R18 - 28 lbs
I guess the bigger hole in the middle of the tire adds extra weight...
245/45R20 has larger overall diameter and circumference than 245/45R18, so more rubber is needed on the outside.
Now, if we're talking about a tire with the same overall outside diameter, just different inner diameter, then yes, the one with less sidewall should weigh less, unless that shorter sidewall is further reinforced, say like 245/55R18 vs 245/45R20.