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Old 10-18-2011, 12:39 AM   #11 (permalink)
puddleglum
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Rondo - '07 Kia Rondo EX
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Quote:
Originally Posted by mcrews View Post
tire hop in the rain is caused by the rain not getting pushed thru the treads.....ie worn uot tires.
Despite what 'might seem' logical, a tire does not "blow up like a balloon'.
Yes, a 10psi tire is flat.
but a tire at 40 psi IS NOT bigger around than a tire at 36psi.
A tire at 40 psi is not curved or bulging in the middle.
First, it just cant happen. there are several steel belts.
second, by design, a tire's flexability is in the sidewall. not the tread.

What I trying to say is that your thought process is a little flawed.
Tires 'wear uot' by wearing against the road. by 'rubbing'. 36 or 40 will make no decernable difference in the life of the tire. BUT it will cost you mpg.

you really ought to review the vast number of posts on this topic.
First, the center wear issue
I'm not convinced you're correct on this in all situations. I thinks it is generally true for low profile tires and it should be true, but I have have had several sets of 75 series name brand tires over the years burn out the center tread, usually at only 35psi. I'm just saying not all tires are created equal.

Second, a tire is going to be effectively bigger at a higher pressure because there is less sidewall deflection, even though the overall diameter doesn't change. Personal example. Last Summer on vacation, tires were set at 43psi, my GPS recorded a 1.8% odometer error. Last trip on the highway, they were only at 38psi and GPS recorded 2% error. I know it's not a lot, but still, they had to be a little smaller with the lower pressure.

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