insa turbo tyres

The Pilgrim said:

I asked in the past, you can compensate wear by pumping 01-02 bar in the rear. I do that and seems ok.

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That's risky, as there's no hard and fast rule as to how much the tyres expand with speed.

It's safest to simply use 4 identical tyres, and rotate them to even out the wear, buying 4 new identical tyres when they are worn out.

The Pilgrim said:

I asked in the past, you can compensate wear by pumping 01-02 bar in the rear. I do that and seems ok.

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Not sure I can see how the maths would work here. While more air may increase the diameter if measured from the ground. The actual radius of the tyre would remain constant. As would the number of revolutions per mile.

The reference is the axle-earth distance. You need rear diameter bigger or equal to front. Bigger psi means bigger diameter, as you mentioned. This is not about tyre specs, is about geometry and phisics.
So, at least in a hurry, pump more, free your mind, protect IRD.

The Pilgrim said:

The reference is the axle-earth distance. You need rear diameter bigger or equal to front. Bigger psi means bigger diameter, as you mentioned. This is not about tyre specs, is about geometry and phisics.
So, at least in a hurry, pump more, free your mind, protect IRD.

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I said diameter from the ground. Not across the tyre. Ie the height with the weight of the vehicle on it. Psi can impact how much deformation. But the total distance around the tyre will be the same. While we “inflate” tyres, they are not like a party ballon that actually stretches. A tyre is a much more rigid construction.

Anyhow, it is your vehicle and potential issue. But I’d suggest that you are maybe only fooling yourself that this is an appropriate way of countering tyre wear and tyres of different heights, with regard to not damaging the AWD system on these vehicles.

Well, allow me an extreme example: big truck before the tunnel / bridge. 2 inch more height, can not go in. Sollution: deflate tyres, lower height (from ground, of course), get the job done.
So, tyres actually are like party baloons, but in a tighter threshold and they hold the car upper or lower as a psi function.
Last try. Why at extreme high pressure the tyre's thread is wearing on the centre?
Rest my case.
Maybe other opinions will bring you light.

Revollution per mile depends only on actual radius, axle-ground.

If the tyre doesn't stretch then it's circumference won't alter, like a tank track.

Sorry for disturbing your peace. I was wrong (was I?)

The Pilgrim said:

Sorry for disturbing your peace. I was wrong (was I?)

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Not really. Or maybe, depending on your individual circumstances.

Threads about tyres pretty much always go like this, you get used to it after a while.

I had this argument a few years ago and experimented with a ride on mower, it went further with the tyres pumped up hard than with them part deflated

landowner said:

I had this argument a few years ago and experimented with a ride on mower, it went further with the tyres pumped up hard than with them part deflated

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The contact area changed maybe, if the tyre is more like a bicycle tyre and pointed in the middle.
We need scientific clarification on this!
As the pilgrim says higher psi and tyre wears in the centre, or is that just because it is the weakest point across the tyre and takes more of the weight or does the tyre in fact flex outwards giving the bigger circumference needed.

Nodge68 said:

It's always best to carry out tyre rotations on AWD vehicles, with the main aim of keeping all tyres to a similar wear.

The Freelander is particularly fussy about tyres, basically all should be the same type, and tread wear reasonably even. However one thing that's absolutely vital is the rear tyres have less wear than the front. Fitting new tyres to the front will cause rapid IRD failure, which will cost more to replace then fitting 4 new premium tyres.

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I do not have prop fitted at the moment could I fit 2 Yokahama A/T tyres to the front I aim to have prop back on in march this year so if I then put front tyres on the rear as they will have a little wear on them and put 2 new on the front would that work?? so I can spread cost of the tyres.

300bhp/ton said:

Not sure I can see how the maths would work here. While more air may increase the diameter if measured from the ground. The actual radius of the tyre would remain constant. As would the number of revolutions per mile.

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I didn't kill my IRD by running on a tyre that had lost pressure then?

That wheel wasn't needing to turn quicker than the others?

Plus of course the radius changes, that is the distance from the ground to the center of the wheel.

J_D said:

The contact area changed maybe, if the tyre is more like a bicycle tyre and pointed in the middle.
We need scientific clarification on this!
As the pilgrim says higher psi and tyre wears in the centre, or is that just because it is the weakest point across the tyre and takes more of the weight or does the tyre in fact flex outwards giving the bigger circumference needed.

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I don't know what google says but with one tyre part deflated on my ride on mower and tipex marks on each tyre the deflated tyre went round more times than the pumped up one, that's the real world