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Discussion Starter #1
Long story short I bought a 190/55 for my race bike and while doing research found something that I would like someone else to verify. Does the 180/55 have a larger side contact patch than a 190/50 mounted on a 6 inch rim??? That just doesnt sound right to me..
 

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Sorry can't answer your question was just wondering where in Dallas you live.
 

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werd
 

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Discussion Starter #5
live in hurst
 

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Discussion Starter #6
does anyone use the 180 on there bike?
 

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livnpaintball said:
does anyone use the 180 on there bike?
I've used both 180 & 190 diablo corsa on the street & track and aside from the 'feel' diff of the two tires i can't tell ya if one is layin down more contact patch than the other.
and i ain't about to get off and look either. :crackup:

BD
 

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I've only used 190/50 and 180/55. Of those 2, I find the 180/55 to be the better. I haven't tried the 190/55 because they tend to be a lot more and I'm not sure you really get any real world benefit.
 

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Rambling :rolleyes:

One of the key theories behind the taller profile tires these days (55,60,70 series) is that when at or near full lean angles as well under accelleration when exiting corners the tires are more compliant due to the tallish sidewall hence they lay down a larger contact patch and i suspect theres something to it as more tire manuf have taken this road.

BD
 

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Just a thougt to confuse things . . .

If I remember my physics correctly the contact patch area is a function of the weight be supported and the air pressure inside the tire. If we were to take the ZX-10R as an example (435 llbs/bike 180lbs rider = 615lbs) and a weight distribution under accelleration of 40/60 front/rear there would be about 370 lbs on the rear wheel. With 30 psi of air pressure in the tire you would need a contact patch of 12.33" to support the bike. This will remain constant whether you run a 190 or a 120.

Would there be something about the 180 that gets to this 12.33 square inches better?
 

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swjohnsey said:
Just a thougt to confuse things . . .

If I remember my physics correctly the contact patch area is a function of the weight be supported and the air pressure inside the tire. If we were to take the ZX-10R as an example (435 llbs/bike 180lbs rider = 615lbs) and a weight distribution under accelleration of 40/60 front/rear there would be about 370 lbs on the rear wheel. With 30 psi of air pressure in the tire you would need a contact patch of 12.33" to support the bike. This will remain constant whether you run a 190 or a 120.

Would there be something about the 180 that gets to this 12.33 square inches better?

Don't forget the geometry of the tire as a factor. All else being equal (tier pressure, weight and weight bias) a 50 series tire will create a 'flatter' parabolic shape than a 55 or 60 series tire a smaller contact patch to work with as you get closer to max lean. Of course, the rule of diminishing returns applies - if the taller series tire reaches near vertical at the edges you lose all feel for where the edge is.
 

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I don't think pressure is the key here. I think tire deformation is more important and that may be the contributing factor to increasing the contact patch. And when cornering the amount of load (G force) on the tire can change considerably, even though the weight of the vehicle doesn't change. Completely different realm, but look at the tires on top fuel dragsters.
 

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That makes me wonder what I have on my ten. I have seen a couple of the local guys with 180's on their litre bikes and it just does not look right for some reason. If I can keep the same turn in characteristics and ahve the same sontact patch then I might check out the 190/55 for the next set once I wear out these dunlops. I was thinking maybe trying a set of powers out otherwise it will be the ole tried and true diablos for me.
 
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