Tire size QUESTIONS??
Thread Starter
Racer
Joined: Feb 2003
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From: cincinnati oh
Tire size QUESTIONS??
I am kind of lost on tire sizes, my friend keeps confusing me. Ok the first number is basically the lenth of the tire and the second number is lower the number is the wider it is right?? For instance i have 2 sets of tires, a set of 255-50-zr16 and a set of 275-40- zr 17 so the 17 rims with tires should be wider but they look the same some one help me i am confused i know there is a technical way of knowing but i want to get rid of the mumbo jumbo and just know the basics lol thanks :steering:
Pro
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From: York PA
Re: Tire size QUESTIONS?? (vettespd20)
Check here. :cheers: http://www.tirerack.com/tires/tiretech/general/size.htm
Team Owner
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Re: Tire size QUESTIONS?? (vettespd20)
First number is the width of the tire, second is sidewall height
You should use 275s or 285s on a 9.5" rim, 245s or 255s on a 8.5"
You should use 275s or 285s on a 9.5" rim, 245s or 255s on a 8.5"
Melting Slicks
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From: If you don't weigh in you don't wrestle Road America
Re: Tire size QUESTIONS?? (vader86)
The first number is width in mm, the second number is what is called the aspect ratio, a percentage of the width. So if you have a 275/40/17 you would take 40% of 275mm so 275x.4 = 110mm the height of your side wall, the last number obviously is the rim diameter. :thumbs:
Le Mans Master
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From: If you read this, you'll go blind
Re: Tire size QUESTIONS?? (96CollectorSport)
The first number is width in mm, the second number is what is called the aspect ratio, a percentage of the width. So if you have a 275/40/17 you would take 40% of 275mm so 275x.4 = 110mm the height of your side wall, the last number obviously is the rim diameter. :thumbs:
Don't you love the mixed english / metric system? :rolleyes:
Thread Starter
Racer
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From: cincinnati oh
Re: Tire size QUESTIONS?? (NeedSpeed)
So 275 means that they are pretty wide right?? And if the 40 means how much rubber from the of the tire to the rims right, and if its a 40 that is why its kinda low profile right??
Le Mans Master
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From: If you read this, you'll go blind
Re: Tire size QUESTIONS?? (vettespd20)
Yes, 275 is the width in millimeters. So since, 1in = 2.54cm,
275mm = 27.5cm and 27.5/2.54 = 10.8in, the width in inches.
Now 40 is related to the sidewall height, and in general a lower number means a lower profile. But, since it is a ratio of the height and width, a tire that is say 205/40 will have a different sidewall height than the 275/40.
[Modified by NeedSpeed, 4:14 PM 12/4/2003]
275mm = 27.5cm and 27.5/2.54 = 10.8in, the width in inches.
Now 40 is related to the sidewall height, and in general a lower number means a lower profile. But, since it is a ratio of the height and width, a tire that is say 205/40 will have a different sidewall height than the 275/40.
[Modified by NeedSpeed, 4:14 PM 12/4/2003]
