Deflating in the First World
Absolute tyre pressure numbers are fairly meaningless as you really need to take the vehicle weight, tyre construction and tyre width into account.
A narrow tyre on a heavy vehicle ( think loaded landrover 130 on 235 width tyres) will run a lot higher pressure and still get tyre deformation than say the same vehicle on a 12.5" wide tyres.
A tyre with more side wall plys will need lower pressures to get deformation as well.
A narrow tyre on a heavy vehicle ( think loaded landrover 130 on 235 width tyres) will run a lot higher pressure and still get tyre deformation than say the same vehicle on a 12.5" wide tyres.
A tyre with more side wall plys will need lower pressures to get deformation as well.
I use the "brick test" to get an idea of tyre pressures (and tyre deformation) for a vehicle / tyre combinations that I don't know.
The pic below is from the test when I fitted the 31X10.5 remoulds to the SJ.
Vehicle is lightly loaded for a day outing
The pic below is from the test when I fitted the 31X10.5 remoulds to the SJ.
Vehicle is lightly loaded for a day outing
- Mad Manny
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I fully agree Wooky.
But these guys generally all had 33's or 35's mainly All Terrain Tyres - one guy had 32's.
So its similar tyres to what we run.
Conditions range from Moab Rock, to mud, sand & even snow.
The Canadians driving off road on snow didn't seem to deflate at all.
In one example (4WD 24/7) they specifically mention only dropping to 1.4KpA & then proceeded to wear their winches out at an incredible rate.
But these guys generally all had 33's or 35's mainly All Terrain Tyres - one guy had 32's.
So its similar tyres to what we run.
Conditions range from Moab Rock, to mud, sand & even snow.
The Canadians driving off road on snow didn't seem to deflate at all.
In one example (4WD 24/7) they specifically mention only dropping to 1.4KpA & then proceeded to wear their winches out at an incredible rate.
"No one ever got stuck - in mid air!"
2010 Fortuner D-4D 4x4 'Fearless'
2006 Conqueror Conquest 'Gearless'
2010 Fortuner D-4D 4x4 'Fearless'
2006 Conqueror Conquest 'Gearless'
It might be an Aussie thing with hard tyres.
Have you watched any of the In skip or Fraser Island video clips on youtube.....Chaos
https://www.youtube.com/channel/UCevp8t ... 3vl3Nnkn1g
Have you watched any of the In skip or Fraser Island video clips on youtube.....Chaos
https://www.youtube.com/channel/UCevp8t ... 3vl3Nnkn1g
- Mad Manny
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Inskip Point reminds us that it's not only Rugby the Australians are piss poor at...




"No one ever got stuck - in mid air!"
2010 Fortuner D-4D 4x4 'Fearless'
2006 Conqueror Conquest 'Gearless'
2010 Fortuner D-4D 4x4 'Fearless'
2006 Conqueror Conquest 'Gearless'
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Depends on area of tread
in contact with the ground ...
in contact with the ground ...
... Famous Fiver VoorLoper ...
... Veni Vidi Vici ...
... Veni Vidi Vici ...
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I did a quick fishing trip to the Nambian Coast this weekend - deflated to 1.4bar all round with four adults and two toddlers on board. I did not get stuck once. And this is with standard HT tyres.
I do get nervous about deflating below 1 bar. A debeaded tyre is no fun.
I do get nervous about deflating below 1 bar. A debeaded tyre is no fun.
Ranger Mildtrak
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- KurtG
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Do yourself a favour and watch the first 8min of this video:
https://youtu.be/jALDz8Y5UvI
2Psi = 0.14bar (no, not 1.4)
https://youtu.be/jALDz8Y5UvI
2Psi = 0.14bar (no, not 1.4)

Flex is overrated
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The biggest reason that guy got stuck was because her drives on the beach the same way he wears his silly little hat. That moegoe would have gotten out with his initial tyre pressure had he reversed on his own partially compacted tracks for about 40-50m, gathered a little but more momentum and did not try to get to the harder soil with such a high angle from his initial line of travel.KurtG wrote: ↑Thu Sep 24, 2020 8:47 amDo yourself a favour and watch the first 8min of this video:
https://youtu.be/jALDz8Y5UvI
2Psi = 0.14bar (no, not 1.4)![]()
He got stuck because he is a moegoe.
Ranger Mildtrak
Scorpio Curry Cruiser
A tos-lookin', lunchbox, lipstick and powder puff carryin' home-built trailer
Scorpio Curry Cruiser
A tos-lookin', lunchbox, lipstick and powder puff carryin' home-built trailer
- grips
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I agree. That were my first thoughts as well why not reverse.Ricoffy wrote: ↑Fri Sep 25, 2020 10:00 amThe biggest reason that guy got stuck was because her drives on the beach the same way he wears his silly little hat. That moegoe would have gotten out with his initial tyre pressure had he reversed on his own partially compacted tracks for about 40-50m, gathered a little but more momentum and did not try to get to the harder soil with such a high angle from his initial line of travel.KurtG wrote: ↑Thu Sep 24, 2020 8:47 amDo yourself a favour and watch the first 8min of this video:
https://youtu.be/jALDz8Y5UvI
2Psi = 0.14bar (no, not 1.4)![]()
He got stuck because he is a moegoe.
You will never find me without Stroh or a 4x4 
