Ok, so I have bought a replacement tyre for my car. It is for the rear and it is a RWD car. The old tyre was 185 70 R14 so the new one is also 185 70 R14, but when I compare it with the other side they are about 1/4" different in total wall to wall width. Why is this, and is it safe to drive it like this?
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the snooper
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yes its safe, is the difference just down to tread pattern ?
Guess so, patterns are obviously different due to different manufacturers, but the overall sidewall width is about 1/4" different. No more then 10mm anyway.
the snooper
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the tyre dimensions 185 mm width of tyre 70 depth of side wall = 70% of 185 and 14 obviously rim size
brianblock
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Isn't the 185 bit the width of the tyre where it sits on the rim? Not at the tread
the snooper
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as far as I know it the widest part of the tyre which is the tread
185 is meant to be overall wall to wall width I think.
the snooper
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no not wall to wall google it
Shox Dr
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take a walk over to The car Bibles.com there's a few pages there, that tells you everything you would ever want to know about tyres rims etc etc.
I'll post this AGAIN, just in case no one bothered to read it
here's a link incase you can't be arsed to google it
I'll post this AGAIN, just in case no one bothered to read it
here's a link incase you can't be arsed to google it
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Hello Wozzaaah,
"Sorry Alec but it is NOT the tread!
The rim the tyre is mounted to is irrelevant, it's the nominal section width measured from sidewall to sidewall."
The reason I mentioned the rim width is a poster mentioned that the 185 in this instance was rim width, which it cannot be. If you are correct and it is wall to wall that dimension is either for a specific rim width or unmounted?
Alec
"Sorry Alec but it is NOT the tread!
The rim the tyre is mounted to is irrelevant, it's the nominal section width measured from sidewall to sidewall."
The reason I mentioned the rim width is a poster mentioned that the 185 in this instance was rim width, which it cannot be. If you are correct and it is wall to wall that dimension is either for a specific rim width or unmounted?
Alec
BeeJay99
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It's so easy to find this stuff on the interweb; from tyrebuyer.co.uk and many more...
"Tyre size code
Vehicle tyre size are normally shown in the form "185/65R15 88H". You can find this size on the side wall of your existing tyre, or in the vehicles handbook.
The first number, in this case "185", is the width of the tyre at it's widest point, in millimeters.
The next number, shown here as "65", is the ratio of the tyres sidewall height to the width of the tyre, shown as a percentage. In this case the sidewall height would be 65% of the width.
The "R" stands for radial, if there is no letter then it is a cross ply tyre.
The third number after the R, in this example "15", is the diameter of the wheel the tyre is designed to fit, in inches (yes, tyre sizes are a combination of metric and imperial units!)
Tyre load ratings
The next part, "88H", denotes the load and speed ratings. The number is the load rating and the letter is the speed rating."
"Tyre size code
Vehicle tyre size are normally shown in the form "185/65R15 88H". You can find this size on the side wall of your existing tyre, or in the vehicles handbook.
The first number, in this case "185", is the width of the tyre at it's widest point, in millimeters.
The next number, shown here as "65", is the ratio of the tyres sidewall height to the width of the tyre, shown as a percentage. In this case the sidewall height would be 65% of the width.
The "R" stands for radial, if there is no letter then it is a cross ply tyre.
The third number after the R, in this example "15", is the diameter of the wheel the tyre is designed to fit, in inches (yes, tyre sizes are a combination of metric and imperial units!)
Tyre load ratings
The next part, "88H", denotes the load and speed ratings. The number is the load rating and the letter is the speed rating."
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