Imperial and Metric Tyre Sizes - Explained

#tyres #4x4tyres #tyresizes

What do the tyre size markings like 205/45/16 or 315/70/18 or 33x10.5x15 actually mean?

How do you calculate the overall diameter of a metric size such as 235/65/17?

Find out in this video...

Tyre size calculators:

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[Javier-bsnr]

After watching so many videos this is probly the best video on YouTube to explain tire sizes.

[TrevorKelly-fi]

Finally something simple. Everyone else is pimping their business making the video 18 minutes to do what you did in 7min.

[NILpotent]

GREAT STUFF. VERY WELL EXPLAINED. GREAT GRAPHICS AS WELL. CLEAR AS A WHISTLE. THANKS!

[tpv]

SUPURB, EXCELLENT.
Extremely Well explained.
'2 Easy'.

[martinsgutmanis]

Thank you for perfectly explaining, I tomorow have exament and this now I now 👍👍👍

[Hals-Ueber-Kopf]

Great explanation, thanks!
At 3:15 you say the last number refers to the size of the WHEEL in inches, obviously you mean the size of the RIM in inches.
But that is nitpicking :D
Keep it up! ;)

[yumiyetpngtv]

Thanks for the very informative video, it really helps me a lot. 👍🙏

[tonyharrison]

Great explanation and helpful website. Thanks.

[allanhugh]

Good explanation, I also used your imperial to metric converter, works well.

[Mike_Costello]

I notice though because nothing is straight forward with tyres that the rim diameter (17 inch) is not really the rim diameter. It's the tyre diameter at the inside lip or edge of the rubber before it is mounted on the rim. The rim size is measuring the diameter of the rim at the part where the tyre lip seats on the rim which you'd need calipers to measure or an engineering diagram of the rim. Placing a tape measure across your rim while it has a tyre on it and mounted to the car gives confusing results. Also a discussion on tyre age and how to read it on the print would be good.

[MattHawk.]

I hate when ppl say rim instead of wheel when they are talking about the wheel. The wheel is the metal unit that attaches the wheel hub to a car via an axle, while rims are the outermost part of the wheel assembly, so you were right the first time and did not need to (in)correct yourself. Tires are tires, not apart of the wheel. Together it is a "wheel and tire". There is no one word for the entire assembly.

[garrysingh]

Hi mate, I have changed tyre and rims to my isuzu Dmax 2013 ( 215/55 r15 to 255/60r18. Since I changed tyre rear break started making noise when I put on a break. I checked brake pads etc they all in good order. Noise only from rear. This vehicle has shoe drums system in rear wheel. What do you think these causing issue? Any advice

[nevillecreativitymentor]

but can you please explain this 13-400x6 tyre ( I am looking at making a Glider GOAT 4 actually and the tyre reccomended is that)
So its a Ultralight Glider

[FrankMomano]

What would the LT truck tires convert to 275/50/20

[rogergregory]

That 4x4 tyre is only 185 ish on the tread size

[christianlords]

160 r13? then there is another number away from this "R670" a japanese import JDM

[crazyjay]

I am amazed tyres mix units. These days I only measure my willy in inches, when I tell the ladies my size they all assume I am talking centermeters.

[NotKnowing]

Why is "tire" spelt "tyre" in your video?

[RoboBeaver]

Brilliant explanation of a fucking stupid system.

[noahtownshend]

Why do some things get decided to be the stupidest way possible and everybody just goes with it