Why do they only make metric size tires for 16" wheels?

Chris

Chris

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Since I still have the 16" Moab wheels on my TJ Rubicon, one of the things I noticed when looking for bigger tires is that every single option out there is a metric size tire. For instance, I can't get an actual 33", I have to get a 285/75r16 or a 305/70r16, there is no 33".

I Googled the crap out of this and even asked the guy at Discount Tire why this was, and no one seems to have an answer. He even told me that he had been doing tires for 15 years and really wasn't sure why.

So, does anyone know the answer? I found that kind of odd that this only seems to be for 16" wheels.
 
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I guess the manufacturer has to pick metric or imperial and since the rest of the world uses metric measure...
go with the flow.

Only the USA, Myanmar and Burma use the imperial measure.
 
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I just find it odd that only the 16" wheel seems to be affected by this. All the other wheel sizes have both metric and inches.

Again, not that I care, it's just curiousity.
 
billiebob said:
On topic / Off topic ??

I find this tire conversion calculator cool since it lists all the options for any size

https://tiresize.com/calculator/

click on tire size calculator first
Click to expand...

I use that all the time, it's very helpful!

Personally I just wish the US would get on board with the rest of the world and adopt the metric system... Sheesh!
 
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they almost beat Canada to it in the '70s....

got to google and find out what went wrong but that said,,,,,,

I still think imperial, mph, mpg, feet, inches,........ I always do the mental conversion.

I remember driving south into Bonners Ferry years ago with a loaded 53' hiboy. The sign said MAXIMUM SPEED 30...
I went down the hill at 30kph thinking there must be a trick coming up....
Then I could see the valley/bridge and light bulb in my head.... Ohh 30MPH not 18mph.
The line of traffic behind me was ready to shoot me... and I realized.. in Idaho they might all be packing.
 
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That's got to be interesting!

I always wonder if people in Canada (and other countries) even have any idea of the whole mph, gallon, inch, feet, etc. thing that we use here in the United States. I'm not sure why the US is still sticking with it, but I imagine at this point it would probably be difficult to change everything, especially when you've got all these vehicles on the road whose speedometers read in MPH.

Idaho... That's a hardcore Republican / conservative state. I wouldn't be surprised if they were all packing =P
 
Canada converted in 1977/1978.... we went thru it.... but I still think mpg.
And a 2x4 has never changed.
A sheet of plywood is still 4x8.
and even tho a cup is 238ml... we still buy a cup of coffee.
 
billiebob said:
Canada converted in 1977/1978.... we went thru it.... but I still think mpg.
And a 2x4 has never changed.
A sheet of plywood is still 4x8.
and even tho a cup is 238ml... we still buy a cup of coffee.
Click to expand...

How funny, so I guess some things never change! That makes sense though, I think things like MPG are pretty universal no matter where you go.

I mean I can't imagine in England they say KPG... Maybe I'm wrong though?
 
No in metric... it is Litres/100Kilometers.

https://www.jeep.ca/en_dir/pdf/2014/fuel_jeep.pdf

sometimes the manufacturer shows both, L/100KM and MPG


wpid-window-sticker.jpg
 
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@billiebob, remember when tires were listed as an example 78P? 2 digit number and a letter? Those were the days when tire size shopping was really confusing. (Just dating myself now I suppose). Yes I know this is an old thread.
 
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This is an old thread but I find it interesting.

@Chris - I never realised that 16" tires only come in metric sizes. I run Duratracs like you. About 3 years ago I purchased a set of 31" tires and put them on 15" Ravine wheels for my TJ. About a year later I picked up a set of 16" Moab wheels and bought on another set of Duratracs. I got 265/75R/16's (31.7") and didn't think much of it at the time because we're used to metric sizes here. To be honest, I thought it was more odd that I originally got the 31" tires.

@billiebob - Using the metric system haunted me for my entire career (lol). I started my working life as a Town Planner fresh out of college in 1973. I retired in 2013. I remember being handed a sheet of conversion factors related to our industry and I still have it. It was mostly for distances (ft. to metres, miles to kilometres, etc.) and areas (sq. ft. to sq. metres, acres to hectares, etc.) and most of us memorized the factors pretty quickly. None of us scrapped our imperial ways though and started to "think metric". The reason of course was that we had to deal with a lot of existing drawings and plans and PEOPLE who were generally older and uncomfortable with the change. ALL of our plans going forward had to be in metric and that was fine by us (it made no difference). Later as a Planning Consultant I recall making a presentation to a Town Council in metric and being blasted by one older Councillor for "speaking metric". I jokingly told Council that we usually based our decision to speak Imperial or metric on the age of the people we are tying to confuse. Most of them got the humour ... and to our neighbours to the south ... we spell funny too.

I don't know if this happened where you are but there was talk in the '70s of changing high school and college football from 3 downs for 10 yards to 4 downs for 10 metres. I'm glad that one didn't fly because I love 3 down football!
 
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Yep, this is one of those oddities I'll never understand. You can look all you want, but you can't find 16" tires in anything other than metric sizes. There's probably other size tires as well that this is true for, but there seems to be no rhyme and reason behind it.
 
Metric tire measurements are stupid. Why? Because the aspect ratio side wall will constantly change height based on the width of the tire. Much more sense if it was true tire width by true tire sidewall height and not a percentage of width. A 285/75 is radically different diameter from a 305/75 even though the aspect ratio is the same.
 
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GASnBRASS said:
Metric tire measurements are stupid. Why? Because the aspect ratio side wall will constantly change height based on the width of the tire. Much more sense if it was true tire width by true tire sidewall height and not a percentage of width. A 285/75 is radically different diameter from a 305/75 even though the aspect ratio is the same.
Click to expand...

X2. I've long though that metric size tires were stupid.
 
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