I've been TireRack tire shopping. Recently, the tire I was leaning toward(Firestone Destination AT) has fallen to number 2, behind the Kumho Road Venture SAT KL61.
This alone is certainly not enough to change my mind, but what I find a little baffling is that the Specs for the FS tire say the overall diameter is larger than the Kumho, but the Kumho states less revolutions per mile.
It is this way in both the tire sizes I am considering.
The Firestone 28.9 diameter LT235/75/15 turns 723 RPmile
The Kumho 28.6 diameter LT235/75/15 turns 706 RPmile
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The Firestone 29.5" diameter 30/9.5/15 turns 706 RPmile
The Kumho 29.3" diameter 30/9.5/15 turns 654 RPmile
The reviews on both tires are excellent, the only complaints on the Kumho are reduced MPG. I'm wondering if the MPG is just being thrown off because the tires are somehow turning less revolutions, due to Firmer sidewalls?
Tirerack states:
Quote:
The revolutions per mile indicates the number of times the tire revolves while it covers the distance of one mile. Depending on the tire manufacturer, revolutions per mile may be either measured in a laboratory or derived from a calculation based on previous test experience.
So do you think one tire was measure in a labratory, the other from previous test results, or do you think the Kumho compresses less under load, and does indeed turn less revolutions per mile, explaining the poorer MPG.
Or do you think the lower MPG reports are due to increased rolling and wind resistance?
If you have any experience with either of these 2 tires you can give your opinion too.
Thanks
This alone is certainly not enough to change my mind, but what I find a little baffling is that the Specs for the FS tire say the overall diameter is larger than the Kumho, but the Kumho states less revolutions per mile.
It is this way in both the tire sizes I am considering.
The Firestone 28.9 diameter LT235/75/15 turns 723 RPmile
The Kumho 28.6 diameter LT235/75/15 turns 706 RPmile
------
The Firestone 29.5" diameter 30/9.5/15 turns 706 RPmile
The Kumho 29.3" diameter 30/9.5/15 turns 654 RPmile
The reviews on both tires are excellent, the only complaints on the Kumho are reduced MPG. I'm wondering if the MPG is just being thrown off because the tires are somehow turning less revolutions, due to Firmer sidewalls?
Tirerack states:
Quote:
The revolutions per mile indicates the number of times the tire revolves while it covers the distance of one mile. Depending on the tire manufacturer, revolutions per mile may be either measured in a laboratory or derived from a calculation based on previous test experience.
So do you think one tire was measure in a labratory, the other from previous test results, or do you think the Kumho compresses less under load, and does indeed turn less revolutions per mile, explaining the poorer MPG.
Or do you think the lower MPG reports are due to increased rolling and wind resistance?
If you have any experience with either of these 2 tires you can give your opinion too.
Thanks