Why no tall thin tyres?

[Chicken Drumstick]

This is more curiosity than anything. But why is there such a limited to no choice of tall thin/narrow tyres?

In days past 9.00 x 16 was fairly common. But today there isn't anything really quite like this. Anything this tall is always way wider.

Even the common Landy 7.50 is hard to come by these days in an aggressive tread with many being just a 235 and different numbers on the sidewall. Indeed I bought some competition tyres a couple of months ago, advertised as being available in 235 and 7.50's. But they where identical when put side by side.

7.50" = 190mm and should be way narrower than a 235.

I understand a thin tyre on a small diameter rim would likely equal a wobbly side wall. But with common 17, 18 & 19" rims, it'd be nice to get an off road biased tall narrow tyre. Something like a 35.7.50R17 or a 37.9.50R17 or 18

Big fat tyres may look cool and serve a purpose on many terrains. But narrow tyres still have a place too, only nobody seems to sell them

This kind of sums it up.

A 235 that is wider than a 255. And we already know 7.50's get passed off as 235's... so a 7.50 (190mm) which is then wider than a 255 (mm) tyre.

And the 9.00 x 16 being sold as a 35.10.50 ignoring the fact that 10.50" is obviously 1.5" wider than 9.00"!!!!!!!!!!!!!!!!

[missingsid]

I must be even older than you then as I see a 9.00 as a wide tyre!

My guess is that they are made for larger trucks than small LRs?

To be honest I am still looking out for serviceable SATs as they are my fav tyre!

Simex are nice but too large for a Series 1 I think??

I notice that the selection shown has one US tyre so always going to be wide, and remoulded which are dependent on the original carcass used.

Marc

[tacr2man]

The width is section width when fitted to the stated rim for that size , so you cant just go measuring the tread width .

The tyre companies make what the market buys , call for 900x16 is small now as most vehicles that used to run those tyres . are now on 17.5 rims eg light trucks. The other thing is as the tyre diameter goes up the vehicle that run those sizes tend to be bigger , and need a higher load rating , which translates into a hard ride when fitted to smaller vehicles , It was the same years ago when fitting a wider tyre than 750 , eg 825 . 255/100 16 is the "new" 900r16 equivalent. The other thing is as tyre size (diameter) goes up the tread patterns required are different as the usage is different , so you dont get the small mud terrain type blocks . HTSH

[Chicken Drumstick]

The width is section width when fitted to the stated rim for that size , so you cant just go measuring the tread width .

I've often wondered if there was a standard on how to measure tyre width, but I can see no evidence of this.

For example, you say the width is when fitted to the stated rim, but most/all tyres have a range of rim widths you can use, e.g.

A BGF MT in 235//85R16 is rated for 6.0-8.5 wide rims. But the tyre is still a 235 no matter which it's fitted too. Other tyre sizes such as a 305/65R17 have a wider range from 8.5-11.0 rims.

And you can't deny that there is a lot of variation in sizes. Take a look at a Michelin XZL in 7.50 and a Fedima Extreme Evolution also in a 7.50.

The Fedima's are almost half as wide again.

[Jamie_grieve]

Is there any evidence for a difference in performance of a tall thin tyre on wet clay, wet grassy side slopes, ice & snow, fuel consumption etc compared to a wider tyre? Should we be comparing contact patches rather than diameters?

[g&t]

I'm no expert but narrow tyres are considered the best choice for snow & mud. Many people retro-fit 235's on Range Rover classics but I stick to the original 205 spec on mine for the aforementioned reason, plus wider tyres result in marginally more strain on the steering & increased road noise.

[garrycol]

Michelin XZL 255/100R16 are tall and narrow and are often used as an alternative to 9.00x16s.

Garry

[tacr2man]

In tests a tall narrow tyre when aired down works better for flotation in sand than a wider shorter tyre , uses less power as well. The footprint of the tyre is relevant to performance depending on what you are looking to do, and by that i mean a lot to do with the surface you are on . eg snow , a very wide low pressure tyre will allow you to travel on top of the snow , but tractive effort will be limited , depeneding on the frangibility of the snow. If on the other hand the depth of snow is limited , then a tall narrow tyre with a smaller footprint will increase the ground pressure and allow to cut thru to firmer ground underneath in order to gain traction .

Climbing a muddy bank a floatation type tyre may severely limit the traction , that is required to get up the bank . Its a very specific usage question that the right answer depends on . HTSH

[101sean]

I used to have 255/85R16 on my 110 which although being larger diameter were relatively narrow.compared to 285s most fit on lifted 110s.

9.00s or 255/100R16 tend to be an almost exclusively military or large utility 4x4 size and very difficult to come by, second hand ones are often old and cracking. XZLs are hideously expensive new but Yellowsea in China are doing a good copy that you can get through ebay, fully e marked and speed rated.. Previous cheap 9.00s like Petlas or Danubiana weren't much better than agricultural tyres.

[discomikey]

i had a set of 235/70 (bambini) insa sahara tyres which measured at 265, i always assumed it was a moulding error or something. maybe not

[ToyRoverlander]

People in general like the looks of a big wide tire, so there's more demand for them so that's what they make and sell... basic economics.

I actually quite like my 315-75x16 offroad. No skinnies for me anymore.

[Chicken Drumstick]

People in general like the looks of a big wide tire, so there's more demand for them so that's what they make and sell... basic economics.

I actually quite like my 315-75x16 offroad. No skinnies for me anymore.

Don't get me wrong, I like big wide tyres too. I usually run some 33.11.50 Simex's. But there is no denying narrow tyres have a place and on certain terrain they do "bite" better. And for me, importantly the vehicle turns better. If you compete in trials, then a tight turning circle and the way it turns is important. And based on back to back tests I have to say narrow tyres do as a rule turn better, and with the right rim allow more lock before you rub the radius arms.

But the thing is, if you want a genuinely narrow tyre, such as a true 7.50 or narrower, you really are limited on what is available and you can't get anything any taller than 31".