<span class="highlight">Tyre</span> <span class="highlight">pressures</span> for 750-16 splits on sand

I had mine down to 18 psi on my landcruiser weighing about 2500kg.
They were never as good in the sand as tubeless tyres

The wider the tyre the lower the pressure you need to get the necessary length of footprint. Why go lower if you're doing OK at 25psi?

Don

You run the tyres as soft as needed depending on the terrain. Roadgrippers can go down as low as 10psi but you have to be aware that you can run it off the rim at that pressure. If you are doing OK at 25psi then that is fine but if you encounter real soft sand then you could go down to 15psi. I have run down to 10 psi on rag tyres to get a larger footprint. Have run a tyre off a rim at 10psi on a radial though.


Cheers

Its about right Ron , just use the ratio formula for width as a first approximation.

I.E. The standard reccomendation of 18psi X Standard width/Your width

So 18psi X 265/195 = about 24psi (195 is 7.50 width)

Hi Don,
I had these tyres on my old HJ45 troopy, which we went Fraser Island with regularly. 25 is about right. The big issue is that you have tubes and the friction can generate a lot of heat at low pressures, I would travel up to 60kph at 25 psi with no worries, just don't steer too sharply. I would go down to 18 if really needed but then had to reduce speed for the extra heat and re-inflate ASAP. Occasionally get out and feel the tyres, if too hot slow down or up the pressures, the fronts can go lower than the rears too, depending on load.

I just posted this in the other place where donk asked this same question....
With tubeless tyres, it is unlikely that you will damage the tyre or valve if you spin the tyre on the rim (a little bit), but you WILL loose all of the air, break the bead seal and get sand between the seal and rim that makes it impossible to re-inflate until it is cleaned properly.

Regarding speed with low pressures, the figures on the pics below are from Michelin for the tyres I use on the OKA.
Notice the dramatic reduction in maximum (sustained) speed that is required to avoid overheating the tyre, even with moderate pressure reduction.


You can also see why low pressures work so well in soft conditions.

Cheers,
Peter
OKA196 Motorhome

Peter - your pics also show the impact of lowering pressures on the width - for sure on hard surfaces and hard sand the tread is still only in contact with the surface but in soft stuff that bulging sidewall (top right pic) also comes into play and the tyre is effectively wider.

People concentrate on the extended length of tread in contact but in sand etc the overall width of that ballooning tyre also comes into play - so your % increase in contact figures are probably a little conservative.

Nice pics and lesson though.

Garry

With beadlocks on tubeless tyres, you can run them as low a 9 psi, of course I'm talking competition setup

I ran my split rimmed 235/85- 16's at 16 front, 18 rear, loaded to 3.5 t on my crossing of the Simpson Desert in '07, as mentioned you have to be carefull because of heat build up (mainly due to speed) and didn't have any problem on any sand dune going east - west, once the sand dunes eased I pumped up to 20/24 psi for the gibber and corrugations along the old ghan line all the way to Alice.
Once on bituman 40/44psi

Image Could Not Be Found
These 2 have done 50000 ks, for a mud terrian I reckon thats good
Image Could Not Be Found
The front pair have only done about 10000ks.

Shane