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Old 08-27-2012, 11:38 PM   #9 (permalink)
ksa8907
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the most i can say on the matter is to suggest anyone contemplating buying a different than stock size consider what that means about the pressure on the contact patch.

the smaller diameter means you have more pressure on the contact patch, because the contact patch will inherently shrink from front to back (think higher angle of attack). if you go narrower instead, you also increase the pressure on the contact patch, but at a faster rate. if you go smaller and narrower, you get much higher psi on the contact patch.

i wont guess at what this means to traction, handling, etc... BUT, the rubber that tires are made of can only handle a certain pressure before it deforms too much, just something to keep in mind. small tires + heavy car = bad.

never thought about it until my met 245 class when we talked about rolling metals. instinct makes you think they would use a large diameter roller, but they actually use a small diameter roller that is actually in contact with the metal, because it has a smaller contact patch and requires less pressure. also there is a phenomenon where once metal starts to deform it deforms rather easily if done fast enough.
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