Tyre size

dee mm

Right here is my issue, have got myself new wheels Now I need tyres, wheels are 16" things, what is the difference in tyre size? ie. 195/45R16 to 195/50R16. Any ideas, thanks.

Seth Brundle

Use a tyre calculator like http://www.miata.net/garage/tirecalc.html

dee mm

God thats a great thing altogether! Thanks!!

Cosworth

Tyre size are displayed on the tyre as you have sais eg 195/45R16.

What this means is that the tyre is 195mm wide the the side wall height is 45% of the width,and the size of the wheel the tyre is to be used on is a 16" wheel.
If you need 195/45r16 and are thinking of getting 195/50r16 instead ,then don't they might be cheaper but you will have a lot of hassle if the car is lowered or if you have a few poeple in the back the tyre will rub off the inside arch.

Cosworth

Forgot to say that the larger 195/50 tyre will also make your speedo less accurate where the 195/45 will keep it as accurate as possible.

Gary.

mike65

Anyone else struck my the fact the tyre sizes are a mix of imperial and metric standards? I mean how'd that happen?

Mike.

Seth Brundle

I think it is because the major tyre manufacturers initially came from countries that use the SI measurements whilst car wheels were initially made in inches (US decision). The tyres were designed metrically to fit an imperial sized rim.
Some manufacturers were tempted to try and convert the double measurements trend and go fully metric (e.g. BMW) but it flopped!
An interesting link about tyres - www.chris-longhurst.com/carbibles/index.html?menu.html&tyre_bible.html

mike65

kbannon wrote:

I think it is because the major tyre manufacturers initially came from countries that use the SI measurements whilst car wheels were initially made in inches (US decision). The tyres were designed metrically to fit an imperial sized rim.
Some manufacturers were tempted to try and convert the double measurements trend and go fully metric (e.g. BMW) but it flopped!
An interesting link about tyres - www.chris-longhurst.com/carbibles/index.html?menu.html&tyre_bible.html

No sooner had I posted, I did a google and found this http://www.madsci.org/posts/archives/mar2001/985878609.Sh.r.html the page linked you linked to is exellent if a little exhausting.

Mike.

Seth Brundle

it is excellent! there is also a page on that site about oils which is good.

Mercury_Tilt

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Seth Brundle

well they mnentioned changing from 195/45R16 to 195/50R16 so there should be no significant amount of torque required.

Mercury_Tilt

This post has been deleted.

Seth Brundle

agreed - many people who upgrade their wheels dont think about the consequences that it may have on their car. Most Qs here about uprating wheels are about whether or not they will fit on, not whether the offset is correct, whether the arches will fit them, etc.