TYRES or TIRES, depends on you country.

[mike smith]

I brought up the subject of Nitrogen in my tyres/tires. I have been told they hold the pressure better, bollocks they do, my pressures are all over the place. A mate of mine has a tyre/tire shop and he says there is no place for nitrogen on a 4wd and he wants to purge my tyres/tires of the gas and just put air into them, so i will let him.

Now about the above topic. The Michelins i have on, although very new when i bought the vehicle, are like bloody great balloons. They are 275/70/16. Now the questions is this, can i fit narrower ones and what effect will it have. I see people put bigger tyres/tires on, why i ask. What is wrong with smaller ones. I cannot afford over $300.00 each for new tyres, but i have found a number of Chinese imports that get great reviews and they are loads cheaper than something like BF or Michelin or Good Year, in fact for a full set of Goodride, it would cost me approx $500.00, now thats a bargain and they are brand new.

I am also reading that the company that makes these tyres, also make many of the far more expensive tyres as this company makes tyres for at least 7 major companies including BFG.

Now any real opinions, without sarcasm please, i get fired up as you know.

 

[moggy1968]

wide for show, skinny for go!!
Unless your somewhere like iceland skinny tyres (which is of course THE correct spelling) will offer significantly better performance off road than wide , providing it's a tall tyre that airs down well.
The whole argument in favour of wide tyres for lower ground pressure is utter bollocks spouted by people trying to justify buying something that is basically just for the look but they won't admit it, or who don't know what they're talking about. To make any kind of advantage in ground pressure you need proper icelandic 44 inch jobbies or bog swampers, but outside those specific environments they will be pretty shit.

 

[Towpack]

Nitrogen does hold pressure better, period. It’s been proven and is used by top race teams for this and other reasons. Wether it is beneficial on road vehicles, 4x4’s or otherwise is subjective. If you’re losing pressure you have a leak(s). What is this tyre company that makes tyres for others including BFG?
I had some Runway Euduro AT’s (Giti Tyre Co.) fitted prior to replacing them with BFG AT’s and I found them reasobably OK on the road but the wear rate was high. At the rate the BFG’s are going I reckon they will last 2-3 times as long.
People fit wider tyres for various reasons. Gererally, for road use, they will improve ride and road holding, maybe at the expense of more road noise due to the increased contact patch but tread pattern obviously plays a part here.

 

[mike smith]

Ok, do you use nitrogen in your tyres, i dont care what the people who sell the stuff say, it does not hold pressure on my truck anyway. My son races a drag car and he only uses nitrogen and after one run of less than 10 seconds, the tyres need to be checked and re filled or emptied as the case may be.

Its a marketing tool to get people to pay to put air in their tyres. I know many drag racers who dont use it, i know many race car drivers who dont use it, because its not easy to maintain pressure. So if you are using it in yours, then good luck if you are not having problems.

 

[moggy1968]

People fit wider tyres for various reasons. Gererally, for road use, they will improve ride and road holding, maybe at the expense of more road noise due to the increased contact patch but tread pattern obviously plays a part here.

your driving a 4x4, not a sports car. In wet weather wider tyres reduce grip and increase the risk of aquaplaning. Wider tyres do nothing for improving ride, a deeper sidewall will do that. Wider tyres are also more prone to effects like tramlining.
Nitrogen is the kings new clothes, just another way for companies to sucker people into parting with their money. I'm not interested in 'subjective' opinion, show me one piece of research that shows any degree of benefit at all in putting nitrogen in the tyres of a 4x4, there is none.

 

[mike smith]

What i am asking is this, what smaller tyres can i fit and what advantage do they have.

 

[Ben Stratford]

Prices and range of some tyres available here for info Mike:

Larger tyres will lift your diffs off the floor Mike. So decide how high you want them. Too big or small may change your gearing. Then look at tyre width as others have said and try to match to how you will use the vehicle. My opinion is wide is for sand or snow, narrow for mud and gravel. On road it doesnt really matter as long as you drive to the conditions. Wider will aquaplane more.
Some tyres last longer and some of these are more expensive.
If you think you will air down and back up then the tyres with side wall strength and tread around the shoulder of the tyre may protect from punctures more easily.
Also think about availability. If you want a matching set but can only get a tyre in sets of 4 or find that only one store sells them in your suze then this could be problematic.
I used runway enduro on an 80 for over 50,000 miles but mostly on road.
Nexen roadian were also very good on road.
Off road, cooper discoverer A/T were very good on my HJ61. BFG A/T on my HJ60 have been very good in Snow and off road. On road so far they have done about 25k miles and still feel good. Just my thoughts Mike.

 

[Towpack]

your driving a 4x4, not a sports car. In wet weather wider tyres reduce grip and increase the risk of aquaplaning. Wider tyres do nothing for improving ride, a deeper sidewall will do that. Wider tyres are also more prone to effects like tramlining.
Nitrogen is the kings new clothes, just another way for companies to sucker people into parting with their money. I'm not interested in 'subjective' opinion, show me one piece of research that shows any degree of benefit at all in putting nitrogen in the tyres of a 4x4, there is none.

Wider tyres can be an issue in the wet in a relatively light weight high powered sports car certainly, in 2+ tons of low powered 4x4 I think not. Tramlining, really? Here in Sheffield I drive on tramlines every day and find the opposite is true. In fact, tramlining (or even white lining on motorcycles) is more to do with tread pattern. The 275’s on my LC ride over the tramlines with ease, my Bro’s car with 185’s is a nightmare. I personally don’t use Nitrogen as I don’t think the benefits are worth the cost/hassle, that’s why I said it’s use is “subjective”.

 

[Animal Mother]

Your tyre size is dictated by a number of factors. If you meet these factors, you can swap to an appropriate size. The factors are:

Rolling diameter - you should try and maintain the factory diameter of your wheel/tyre combination, in order to; ensure the speedo is accurate, maintain correct gearing, not place undue stress on driveline components. Some differentiation is acceptable though (that's where the tyre calculator link below will help).

Wheel width - the wheel width will dictate the maximum and minimum tyre width.

Wheel diameter - wheel diameter will, in some cases, may reduce the availability of some tyre brands/models.

Use this: https://tiresize.com/tyre-size-calculator/

A good tyre option for you (avoid the cheap chinese shite) would be 265/75R16 Cooper STT. You'd gain a little (acceptable) diameter, lose some width (within the acceptable width of the wheel I believe) and get yourself a reasonably priced well regarded tyre.

 

[clivehorridge]

wide for show, skinny for go!!
Unless your somewhere like iceland skinny tyres (which is of course THE correct spelling) will offer significantly better performance off road than wide , providing it's a tall tyre that airs down well.
The whole argument in favour of wide tyres for lower ground pressure is utter bollocks spouted by people trying to justify buying something that is basically just for the look but they won't admit it, or who don't know what they're talking about. To make any kind of advantage in ground pressure you need proper icelandic 44 inch jobbies or bog swampers, but outside those specific environments they will be pretty shit.

I’m not taking issue here, the tall & skinny vs short & fat debate has been raging for years and probably will continue...

I’ve no problem with the “wide for show, skinny for go” scenario, but I like wide and certainly don’t mind admitting that it’s partly for looks, but I can’t rule out other benefits.

“skinny tyres (which is of course THE correct spelling) will offer significantly better performance off road than wide, providing it's a tall tyre that airs down well”.

Isn’t that a contradiction in itself? Why air down? I know the answer, to increase the footprint, so why not have a bigger footprint in the first instance?

I’m not arguing either way, to me it's down to personal preference and personal experiences. It’s just that every piece of justification for either argument seems to fail.

IME, the only time I’ve felt unsafe in my 80 on asphalt was when I had the original tyres on it which were in good condition, but were 215/80/16s, on the standard steel 7” wide rims, bloody lethal on the road IMO, especially in the wet.

Sorry Mike for not addressing your question yet, or maybe I have. I can only say I wouldn’t go narrower than the width recommended by Toyota, you’re likely to compromise your insurance if nothing else.

 

[moggy1968]

I’m not taking issue here, the tall & skinny vs short & fat debate has been raging for years and probably will continue...

I’ve no problem with the “wide for show, skinny for go” scenario, but I like wide and certainly don’t mind admitting that it’s partly for looks, but I can’t rule out other benefits.

“skinny tyres (which is of course THE correct spelling) will offer significantly better performance off road than wide, providing it's a tall tyre that airs down well”.

Isn’t that a contradiction in itself? Why air down? I know the answer, to increase the footprint, so why not have a bigger footprint in the first instance?

I’m not arguing either way, to me it's down to personal preference and personal experiences. It’s just that every piece of justification for either argument seems to fail.

IME, the only time I’ve felt unsafe in my 80 on asphalt was when I had the original tyres on it which were in good condition, but were 215/80/16s, on the standard steel 7” wide rims, bloody lethal on the road IMO, especially in the wet.

Sorry Mike for not addressing your question yet, or maybe I have. I can only say I wouldn’t go narrower than the width recommended by Toyota, you’re likely to compromise your insurance if nothing else.

Evidently you don’t understand how airing down works, or the negative effect of a wide tyre in situations where airing down is beneficial. There is no contradiction if you understand how it works. This is well documented by people considerably more knowledgeable than us and the information is out there if you care to look. I am not suggesting going narrower than the manufacturers recommendation (although that recommendation in the uk may be driven by fashion rather than function and may well be different in other markets where function is more important). Your argument about wet weather performance is also contradicted by all the well researched scientific evidence out there and your experience is more likely down to the type and make of tyre rather than anything else. A narrower tyre will be less prone to aqua planing than a wide tyre of the same make and tread pattern.

 

[moggy1968]

Wider tyres can be an issue in the wet in a relatively light weight high powered sports car certainly, in 2+ tons of low powered 4x4 I think not. Tramlining, really? Here in Sheffield I drive on tramlines every day and find the opposite is true. In fact, tramlining (or even white lining on motorcycles) is more to do with tread pattern. The 275’s on my LC ride over the tramlines with ease, my Bro’s car with 185’s is a nightmare. I personally don’t use Nitrogen as I don’t think the benefits are worth the cost/hassle, that’s why I said it’s use is “subjective”.

That rather depends on the width of the tyre doesn’t it! Modern 4wds produce a decent amount of power and a lot of torque, but that’s not the point, your ability to stop and get round a bend bears no relation to the amount of power your vehicle produces (unless your getting into the realms of power oversteer) Yes a 4x4 weighs more than a sports car (which also has significantly better brakes and handling) but the tyre size specified by the manufacturer is the optimum for that type of vehicle, going wider than that is likely to be detrimental in the wet. High performance sports cars can be quite a handful in the wet, that’s why wet weather tyres for racing are narrower than dry ones. It’s all relative. A wider tyre also tends to have a squarer profile making tram lining more of a problem, although I’m not sure to understand what I mean by tram lining, it’s nothing to do with trams!! It’s very dependent on the individual tyres profile I’ve had different tyres of the same size and some are worse than others, it depends principally on the edge profile.

 

[Towpack]

I know exactly what you meant by ‘tramlining’, hence my mention of ‘whitelining’ on bikes which is how it’s always been referred to. It’s more to do with tyres following the contours and imperfections in the road surface. The term was derived (obviously) from the effect of driving over real tramlines. My mention of them was to put a perspective on the problem. Driving on even the most poorly hard surfaced roads is nothing compared to real tramlines. If the vehicle and tyres can handle those without much problem then I can’t see ridges or lines or overbanding etc being issue.

 

[Gr8Yota]

On the Nitrogen question my understanding was the advantage was that you don't have the same moisture as with air? On the leakage...if your wheels/tyres leak they'll leak air or nitrogen regardless. Be sure leakage isn't confused with variations of pressure due to temperature.

On the skinny or wide it depends on the terrain you wish to cross, the vehicle weight and personal preference for your driving style. I like to stay close to OE but increase the height if/as much as possible without needing to re-gear. I ran 255/85 R16 on my KZj70. Currently run 285/75 R16 on my FJ so wider but better suited to the vehicle I think.

 

[Shayne]

Standard tyres are likely chosen simply so they can lie about fuel consumption , but bare in mind they have to estimate what kind of driving you do .

Smaller tyres will give better mpg around town because its all stopping and starting , a pushbike with little wheels is much easier to peddle up hill than one with big wheels .

But if your doing long distance at high speed bigger tyres carry you further for less effort so better mpg .

The fat v narrow tyres debate for me is a no brainer , in all but very specific situations the narrow win hands down which is why the worlds military run skinny tyres , they just look rubbish .

I cant find tyres fat enough for my liking but i don't give a damn about fuel consumption and never have my fat tyres failed me where skinny tyres might not have .

This here is a handy website if your considering alternative tyre sizes http://www.kouki.co.uk/utilities/visual-tyre-size-calculator

 

[Chas]

“skinny tyres (which is of course THE correct spelling) will offer significantly better performance off road than wide, providing it's a tall tyre that airs down well”.

Isn’t that a contradiction in itself? Why air down? I know the answer, to increase the footprint, so why not have a bigger footprint in the first instance?

I've always been led to believe that airing down doesn't alter the width of a tyre (well very little) it's the length of the footprint that changes and gives extra grip.

 

[MarkW]

Correct Chas its essentially a caterpillar track effect from airing down

on road wide low profile tyres are the best option for performance although can result in more tramlining and a harsher ride

best grip in the dry is a slick tyre, but downright dangerous in the wet

best wet tyre is by far Uniroyals Rainsport, these are astonishingly good. A friends very low powered fiesta wipes the floor with cars with 300+bhp at Castle Combe in the wet, not to shabby in the dry either

Off road tyres will never perform as well on tarmac as a road tyre.

Skinny vs Fat is an age old debate both have different advantages. There has been a great video around after the snow of an old model T ford on skinny tyres driving past 4x4s.

Nitrogen is only worthwhile for high end race cars where every fraction of a second counts, otherwise its a sales gimmick to extract more money from you

 

[Towpack]

Smaller tyres will give better mpg around town because its all stopping and starting , a pushbike with little wheels is much easier to peddle up hill than one with big wheels .

IME a push bike with smaller wheels is no easier to pedal up hill, that's just down to gearing. A bike with small wheels will obviously be geared differently to one with big wheels for a given speed. In fact, a small wheeled bike will be harder to pedal on anything but a really smooth surface as the wheels will feel the smallest potholes and undulations where a big wheel would ride over them. That's why off road dirt bikes have 21" front wheels and not the 16-17" found on most road going motorcycles.

But if your doing long distance at high speed bigger tyres carry you further for less effort so better mpg .

Again, this is down to gearing. Bigger (diameter) tyres will of course be turning slower but, in raising the gearing and the fact they will be heavier will make the engine work harder. That's why some go to the expense and effort of changing diff ratios when tyres much larger than OEM sizes are fitted.

 

[Shayne]

Yes i understand its all about gearing Towpack but for us its a toss up between higher speed at lower revs (big wheels) or increased torque for easier take off (little wheels) we cant alter one without altering the other so its a case of finding the happy medium which would be much easier if the world was flat .

Your a motorbike fan i think so like me you probably have in the past increased power and fitted a smaller rear sprocket to increase speed , I apply the same thinking to my truck and i'm sure if it was as simple as just changing a sprocket i could go down a size without a worry .

Its never far from my mind that the KDJ90 i have runs slightly taller gearing than my more powerful (modified) KZJ90 and an axle/diff swap might well improve the way both trucks perform on 33" tyres .

 

[moggy1968]

I know exactly what you meant by ‘tramlining’, hence my mention of ‘whitelining’ on bikes which is how it’s always been referred to. It’s more to do with tyres following the contours and imperfections in the road surface. The term was derived (obviously) from the effect of driving over real tramlines. My mention of them was to put a perspective on the problem. Driving on even the most poorly hard surfaced roads is nothing compared to real tramlines. If the vehicle and tyres can handle those without much problem then I can’t see ridges or lines or overbanding etc being issue.

That’s ok, it was the way I read it, had visions of Sheffield trams!!