Outer Limits 4x4 Board

Hey guys - havent done much sand driving on my 31's and im heading to the dunes over new years - im running cooper stt's. With the 10.5" tyre, is it really worth letting it down on sand? Im thinking increasing the width of the tyre is just going to bog me down and im better to keep them at road pressures (20psi) to keep them on the skinnier side (not that 10.5" is skinny under a zuk). Obviously the tread pattern is going to be digging me in anyway - i just want to make it as easy on the engine and clutch as possible!

Thoughts? Ideas?

its a zook, it will float on the sand anyway!!!

but letting the tyres down doesn't increase the footprint width, moreso the length. which is a good thing on the sand. the larger the surface area you have on the ground the less you will sink.

why do you think the big cranes put wooden sleepers under their outriggers (feet)? its because it spreads the load over a larger surface area and they dont sink into the ground

I would suggest letting them down.I recently tried my zook with 32 in mongrels on a very soft beach down here and it certainly made a difference even with the light weight of the car.I ran them at 12psi in the end so i could get them to bag out a little but its tread length that you want not width which gives you the flotation.

alien wrote:Hey guys - havent done much sand driving on my 31's and im heading to the dunes over new years - im running cooper stt's. With the 10.5" tyre, is it really worth letting it down on sand? Im thinking increasing the width of the tyre is just going to bog me down and im better to keep them at road pressures (20psi) to keep them on the skinnier side (not that 10.5" is skinny under a zuk). Obviously the tread pattern is going to be digging me in anyway - i just want to make it as easy on the engine and clutch as possible!

Thoughts? Ideas?

Its also (if dune running) the extra few inches of compression travel you will pick up ..

more boot and revs.

my 31 mudders love it in the sand.

got to keep them spinning thou

mine get let down to 12 usually but down to 5 quite often.

challenge!

have a go at 20 psi and see what you think!

then go down as low as you dare. I used to go 5 psi on 30 inch and the same on 37 inch mtr. but whatever your comfortable with! I never had a problem and I find it funny when people suggest to let tyres down to 15 psi or so! its a zuk it weighs 1/3 a patrol so put your tyre pressures to suit!
its more about how they bag and look then the actual measured pressure!

20 psi was my road pressure and a visual on the tyres was my psi on sand which was nice and bagged!
if anything run the fronts with a bit more than back as the front will cop side loading while steering. while the back just need to push that sucker as hard as possible up hills!

if your on stockton beach this chrissy/ new year! look out for my stocker lwb blue zook floggin around!

hope that gives you some info
cheers ashley

X2 it's always all about the length of the footprint, not the width.

Let them waaaay down.

Steve.

yeah i know its about length - i was just wondering though if the width was going to adversely affect any gains in length though - but it seems not =)

I used to run my 215/75s at about 7psi in the sand, but now with a 31 i reckon 7psi would be needing beadlocks to keep it on the rim =) hehe

Thanks for the input fellas!

alien wrote:
I used to run my 215/75s at about 7psi in the sand, but now with a 31 i reckon 7psi would be needing beadlocks to keep it on the rim =) hehe

Thanks for the input fellas!

not having a go! just wondering why? whats your theory on this?
ashley

I barely even notice my 31's bagging at 12psi. 5psi would be ok, just drive accordingly

used to run 32 mongrels and heaps of times id get stuck in the sand
if i stopped and tried to take off i would dig myself 2 huge wholes lol

once i lowered my psi to about 20psi i was fine
i wouldnt go much lower though dont know how the tyre would handle it

germo wrote:

alien wrote:
I used to run my 215/75s at about 7psi in the sand, but now with a 31 i reckon 7psi would be needing beadlocks to keep it on the rim =) hehe

Thanks for the input fellas!

not having a go! just wondering why? whats your theory on this?
ashley

taller tyre on a skinny rim (15x7's) - the tyre has more leverage on the bead than a smaller tyre, hence can pull the bead off the rim and leave you scratching your head as to how to get it back on in the middle of nowhere =) lol

alien.

mine spinning hard and my style of driving and on 5psi never had a prob with the 31s on 7' rims.

go 10-12 to be safe and then have fun.

8 psi cold or 10 psi hot, just enough to see them bag out.
bfg's and tyres with harder sidewalls generally take a bit more. I run 31 maxxis mudders

nicbeer wrote:alien.

mine spinning hard and my style of driving and on 5psi never had a prob with the 31s on 7' rims.

go 10-12 to be safe and then have fun.

hahaha well if your driving style wont break the bead then mine certainly wont =)

wideaz wrote:used to run 32 mongrels and heaps of times id get stuck in the sand
if i stopped and tried to take off i would dig myself 2 huge wholes lol

once i lowered my psi to about 20psi i was fine
i wouldnt go much lower though dont know how the tyre would handle it

20psi is road pressure, no wonder you were digging holes. 10-12psi is good.

nicbeer wrote:alien.

mine spinning hard and my style of driving and on 5psi never had a prob with the 31s on 7' rims.

go 10-12 to be safe and then have fun.

I run 9psi on 31X10.5" pedes on 8 inch rims. I'd go 5 psi there abouts on the same tyres on 7 inch rims. Prolly add a few psi for radials.

alien wrote:

germo wrote:

alien wrote:
I used to run my 215/75s at about 7psi in the sand, but now with a 31 i reckon 7psi would be needing beadlocks to keep it on the rim =) hehe

Thanks for the input fellas!

not having a go! just wondering why? whats your theory on this?
ashley

taller tyre on a skinny rim (15x7's) - the tyre has more leverage on the bead than a smaller tyre, hence can pull the bead off the rim and leave you scratching your head as to how to get it back on in the middle of nowhere =) lol

I have 31" baja clawds on 8" rims, I run at 5psi everywhere, neven on the road, as its only a cuppla K to the sand from home.

I have had my lil girl on 2 wheels a few times, never broken a bead.

At 20psi she struggles in 4wd, the sand is very soft, at 5psi, 2 wheel drive and no drama, floats like a boat.

i let my 31 trepadors down to 5 when i'm out on rocks. then drive it home. i wouldn't hesitate doing the same when i go up to stockton.

I don't reccomend driving over 60km/hr or very far on anything less than 15psi.

I was amazed how much easier it was to drive up dunes with lower pressures is! More so in my cruiser with 750/r16 than my zook with 32's. I found the magic number for the zook to be about 8psi the tyres are just bagging out nicely and don't look like popping a bead at all even when given them a hard time