Thin tyres v Wide tyres on sand

I still have skinnies on my hilux and have never had a problem on the sand. Been to Stockton a couple of times when the sand was very soft and never required snatching. Just keep your pressure down and you'll be right.

Cheers

I've had skinny tyres and fat tyres over the years with different 4x4. I now have a troop carrier. Until last weekend I have never done a direct comparison between 750x16 Road Grippers on 5.5 inch split rims (standard fitting for 78 series troopy) and BF AT 265x16 on 8inch 100 series rims on the same vehicle in the same sand. I had a preference for the split rims for the all round bush combination, ease of changing tyres etc.

Last weekend I fitted a set of BF ATs and went back to Bribie Island to test where I had previous difficulty. Set at 25psi was amazed at the difference. Probably half the engine effort. I deliberately went into the softest sand I could find and was left very impressed.
The only downside is changing the tyres with R&R beadbreaker I found it impossible to get the bead to set so I could pump them up. That leaves me with a worry of changing them in the bush. The local tyre man gave me some tips on how to get the bead to stick but I haven't had the oppotunity to try that out yet.
So, yes you can get where you want with skinny split rims but you can further with less effort with more suitable fatter tyres.
Just my experience.
egards
Ian

ditch those poxy cheese cutters NOW!!! :)
yeah theyre great in the bush if you wanna repair a tyre... but i mean really - how many flats have you had that you couldnt repair ON the rim? maybe i don't get out enough :(

and Willem I know you're a split rim fan... as was my old man (probably for similar reasons... simple, dependable, one less thing to go wrong, etc - same reason he hated electric windows, electronic dashes... anyway - im getting away from the point)

from a practicality / repair point of view they are great... from a looks point of view they are ordinary.

as far as how they perform in the wild... i only did some light sand work with the old splits before i switched to the (slightly) wider 235's.... the 235's seem to bag out better at higher pressures - if you're prepared to go below 18 psi you get good results with the splits... with the 235's i can sit on about 22psi and get a similar contact patch.

but then again... i have read others on here post that they live in the desert and they run splits because they perform BETTER on the sand than the fats!!!

no doubt you'll get a lot of conflicting views on this topic... something you need to weigh up for yourself i guess.

cheers!

KG

Its not the width but the length hats inportant so the skinnies would do the job just like the fats. Whatever you reckons a fair thing, although 235/85's are a great thin/fat compromose, had em on my Mav and they were great.

Bonz is on the right track here. When you deflate your tyre, sure the sidewalls 'bag' out. But your tread doesn't get any wider and it's not your sidewalls thats keeping you up, it's the tread 'flattening' out front to back. You are getting a longer contact patch, not a wider one.

As to skinny or fat? Well, it's debateable but IMO your vehicle works a bit harder with fats as it IS pushing a little hill of sand in front of the tyre and the wider the tyre, the wider the hill it is trying to climb over. But the difference is probably so small as to be "a bee's d!ck of **** all".

akarosco, stick with your skinnies for the cost factor of changing over to wider rims and tyres.

SK

After running fat & skinny tyres on 3 different cars I found very little difference between them. The narrow ones may sink deeper but push a small amount of sand in front. The wide tyres float higher but the hill of sand in front is also wider.
If I had to pick, the fats would have a slight advantage in some sand conditions although I prefer the bulldozer approach.(long & skinny) Cheers Craig...........

akarosco.
750's are the go on sand. as stated by others, I was watching a documentary on the Sahara desert, there were 2 vehicles, one with 750 and the other had wide 15" tyres,the one with the 750's was towing the wide tyre machine over the dunes.You dont get dryer sand than the sahara. Eric.

I may be the only member here to run fats 275/75/16 and standard 750 / 5.5 skinnies on the same beach the same day, the time difference was changine the tyres in the car park. Why??? I had to settle this arguement for my self. The results the skinnies were a little bit slipery on the back end. thats it! it went just as far. Test beach was Tims thicket WA Tyer presure was same 15-18 i think but both set by Staun tyre deflatores.

My experance on a diff beach.....I pulled my camper @ christmas over river mouth @ Pallingup ct weight was 750+ I got through on 12-15 psi all round. Coming the other way was a Hilux towing a boat being pulled by another 4wd, the hilux had fats.

Post 9117 said I was stupid but my reply I saved as I couldnt load it was
"My view is that you are no better off in the pocket !!!!!!!!!!!!!!!!!! "
Quiet the contra, I needed tyres and rims for my new camper as it uses less fuel rolling rather than scraping away the metal, lol. New set of fats was $1200 and I don't think they performed well on the beach, so why buy more of what you don't like???
MY $ MY choice I choose to have 2 spares on the CT (extra spare was < $200) as apposed to $2000+tyre/rim for a duel wheel carrier on 4wd (you do the maths)
Ps I think long term Round oz next year 3lt better of for every 100kms (30,000 km,s x 3%saving = $900 saving) (wow I think they now add up to FREE) and I can have up to 3 flats before I need to fix 1 up in the cool of the day not the heat!!!!
PPS everybody has diff needs

I should + the skinnies are 3 kms better or the fats were 3kms error (gps)

Hope this helps.

Go with the Wider tyre as they give better flowtation as the print is almost the same as a skinny but twice as wide. The 4by will flow along the sand with less effort in my experience.

33 X 12.5 Muddies on 15 X 8 Sunraysia's didn't stop us on Fraser Island. More than once. Anywhere! Including the tracks that we were advised to stay away from 'cos they're too soft, (by people on this forum amongst others!)..... Indian Head, Northern Tourist Track, Wathumba Rd et al..... at 22 psi as well, and no track damage 'cos no wheel spin.
Just my 2c worth
Not trying to inflame a tyre war, just relating what works for us.
:-))

I seem to remember a comparo done between skinnies and wides in a 4wd mag last year (i think it was) and the wide tyres won in the overall sand, mud and rock traction stakes based on better flotation as mentioned in a reply above.

Sorry i can't remember which mag but i do read 4wd monthly more than any of the others so it could have been in there. It was heralded as the definitve wide vs skinny tyre test or something similar.

Once again, lots of variables..

Tire conditions, suspension, weight of car, weight of drivers right foot, weather conditions....

We did Robe last Oct with the club, 2 convoys of 8. All with 10.5/12.5's, and only once did we strike an issue, that was an unexpected washout, one bloke stood on the picks and car behidn nearly ran up his ginger. So we had 2 stuck.

But as for driving around, all running 18psi, not an issue. One flat tire on a rocky shelf, but could have been driver issues.. ;)

There are arguements for both.
Thin will cut in and dig, wide will push etc..

Trial and personal preference really. I havent had cheeze cutters, so cant comment, but 90% of 4b's that we saw at Robe had 10.5s at least.

YMMV

akarosco have a read of this tire bible

Scroll down about 2/3 of the page and you'll find a bit on contact patches.

Generally on sand, if the contact area were the same, skinny and long is better than wide and short. This is true because the narrower leading edge creates a small area of sand build up over which it must climb (it's like a mini hill being constantly created in front of the tyre as it pushes through the sand. It has nothing to do with floatation (remember the contact area is the same) but the vehicle will not work as hard to maintain forward motion so it will use less fuel.

One problem with the 750R16 on split rims though is that because of their construction you cannot safely reduce pressures to the same degree that you can with a radial on a JJ rim. This means that you you are more likely to be able to achieve a bigger contact area with a radial and therefore achieve better flotation.

Flotation depends entirly upon the contact surface area and the weight of the vehicle. Unfortunately, it is almost impossible to determine what the contact area would be for any given tyre at any given pressure without doing a test similar to that doe by 4x4 Monthly some time ago (where they fitted different tyres at different pressures to the same vehicle, jacked the vehicle up and inked the tyres and then let it down again onto pieces of paper to get a "foot print").

Sorry :)

I got bagged out last time I made a comment about wide tyres on this forum, however I stick to my guns, I have had skinny tyres and I've had wide tyres, there is a lot of sand here in WA, and wide all the way mate.
But don't be fooled, wide does not mean you don't let your pressures down, you let them down the same amount as you would with skinny tyres, otherwise your wasting your time.

I reckon I get better traction on Sand when I let my tyres down from 25psi to 20psi on the Sand. Whether it was on the original HT's or Cooper ST's, the lower pressure makes big difference.

Currently runnning 30*9.5 Cooper ST's - run them at 20psi and they go anywhere on Sand.

Cheers,

Glenn.