Quote:
Originally Posted by JSH
Larger diameter tires have lower rolling resistance than smaller diameter tires.
Web quote: Tires with a smaller diameter have a higher rolling resistance with the same inflation pressure, because tire deformation is proportionally greater. The tire is flattened more and is “less round”.
This is one of the reasons why giant wheels / tires are all the range on EVs. This is why BMW had special skinny 19" tires made for the i3.
However larger wheel / tire combos tend to be heavier which increases rotational mass and consumes more fuel when accelerating - which hurts city mileage. As with everything there are tradeoffs.
|
Not true, tires with a smaller diameter only have less contact area (resistance) if they are not inflated to a equal weight ratio pressure. Which if you were changing wheels is not something you would miss. In real driving enviroment the net efficiency of smaller lighter wheels is larger so as phase says swapping for smaller wheels whether highway or not is still more efficient
Also using a 5.5j/185mm tire on a regular car pumped up to low contact would have very low grip in wet conditions irrespective of the overall diameter