How will a standard LC 200 go crossing the Simpson?

Hi Allan

Many thanks for your fast reply and great to learn from your experience and I will ensure I get a quality flag and keep it pointing upwards!!

Re the tyres I am currently running the factory equipped Dunlop Grandtrek AT22's on 17 rims. Toyota are using them on the FJ's and LC and I think a similar version on the Parados. They appeared to be more of a road tyre so I checked the Dunlop website though found no real information. I have emailed Dunlop today to see how they stand up at low PSI though so far no answer. I will share if they respond.

Cheers
Bluey

Bluey, The AT22's should do fine at lowered pressure on sand. Perhaps not the most robust tyre for rough tracks with rocks but fine for highway and sand.

The whole objective of lowering tyre pressure for sand is to increase the tyre's footprint and aid flotation. When the tyre pressure is lowered to 20psi and below, the sidewalls are considerably flexing with each revolution so a more flexible sidewall will generate less heat. Of course, your speed would also be significantly less under those conditions which compensates to some degree. Tyres with stronger sidewalls are less likely to be staked but do generate more heat at low pressure due to flexing of the sidewalls.

I am currently running Cooper S/T. A reasonably wide tyre with flexible sidewalls. They perform well for my heavily laden Troopy on soft sand but they chip and wear rapidly on rocky roads. I have tyre pressure/temperature monitors fitted and have observed no more temperature increase at low pressure with low speed than at high pressure & high speed.

Of course, it is necessary to carry a reliable air compressor to reinflate your tyres. Get the largest you can afford or be prepared to wait long times to get the pressures back up.

Thanks Allan for the advice and education, its interesting and makes good sense.Dunlop never came back to me, I hope their tyres as a lot better than there zero customer service. Either way I will post an update once I have made the trip.

Cheers
Bluey

Bluey

You are going to have a ball. Both in setting the car up and actually going on drives. You wont get it right the first time so be prepared to acknowledge "Hmm Maybe that was not a good buy".

Just a variation on Allans post. For tyre pressures, we ran 20 PSI front and 26 PSI rear all the way from Oodnadatta, up past Finke to Chambers then through Mt Dare and Andando, the Simpson to near Birdsville. That works for our heavy 100 series with Cooper ST Max's 285,/75/16 tyres on the rocky roads in the Victorian high country and gravelly roads, corrugations and sand. We have also never had trouble in water or mud either.

About the compressor. I wouldn't necessarily go the biggest. Time in the outback is nothing. Look at where it is goiung to be stored, what you are going to use it for (lockers etc) and how big or small your budget is.

We got just the ARB CKMA12 – High Output On-Board model and it is installed in a void beside the drawers in the back of the car with a bulkhead outlet mounted right near the tailgate.

Phil

The sidewinder compressor came up as the best bang for your buck in 4wd action magazine (vol 31) comparison. 3rd best for 1/4 the price of the very expensive ones and only a fraction slower the the ones at the very top. Stand by their guarantee too. I'm a satisfied customer not a sales rep. Very worthwhile accessory IMHO. The online vendor offers exploroz discounts as I recall... My 10c.

Phil,

Lowering tyre pressure is not just about "never having trouble". Its also about minimising track damage. You may well succeed in climbing dunes with 20/26 psi but you may also be leaving some track damage behind for following vehicles to cope with. There is no honour in managing with the highest pressure possible. Any more than those who proclaim that they can "do it in 2WD".

The Ranger at Dalhousie Springs told me that he runs at 15psi all round at all times....... and I would think he would know what he is doing.

Phil,

We run 305/70/16 Cooper S/T and on our trip across the Simpson we ran 16 in the front and 17 psi in the back. We weigh in at 3170KG two up with a full fuel and water load. To get to that weight we carry only the bare essentials.

At those pressures and tyre width we get good flotation and do minimal damage to the dunes.

At your own admission you are running about 600kg overweight and at 20/26 psi on fairly narrow tyres there must be some dune damage.

Lyn

Lyn

I would not call 285 tyres "fairly narrow tyres". That's a bit below the belt and not called for. They are the widest that the RTA will permit to be fitted to my car and two tyre sizes wider than fitted at sale. I would love to know what you drive?

One trick I learnt a few decades back was to look at your tyre marks to see if you are running a reasonable pressure. I do and I am.

Re our weight: One day I will weigh the car. It's all been a guess so far. You never know I may be legal and surprise even you!!!

Lyn

I will apologise for having a go at you in my previous post. Also as one of your posts was removed I also think that I upset you and you responded in like manner.

As any other woman who read my posts would know, I have an incurrable cancer. It does not allow my blood to be fully oxygenised and thus I do not have much energy and can not climb or walk far. This series of trips are a real bucket list. We do not want to damage the environment and even carry our own toilet, wood and a large rubbish bin on the rear spare. No waste in the desert. No collecting wood that may be a home for the local fauna, nor leaving the beer can on the side of the camp ground etc etc.

The chemo also stuffed up some of the old brain waves and I get a little carried away. I tend to exagerate, as a lot of men do. Especially fishermen about their catch. Life at home must be a real pain for my wife, but she doesn't complain.

Thus I get "protective" and tend to missread posts.

Cheers

Phil

Hi

As has been discussed many times before the width of the tyre is irrelevant (past a certain point well below the width of available tyres for 4WDs) for sand driving...its the LENGTH of the tyre footprint that is important - reduced pressures increase the length of the tyre footprint which dramatically improves performance in sand..any increase in width (existing or caused as a result of reducing pressures) is inconsequential from a performance point of view - they may look better though :)

A “wide” tyre at the wrong pressure is just as bad a “narrow” tyre at the wrong pressure in sand. At a guess I would say "damage" to dunes is mainly caused by people with the wrong tyre pressures ...not by those with "narrow" tyres.

Nothing wrong with Phils tyre choice (with respect to width) IMHO. My tyres are even narrower (235, albeit a smaller car) – no problem on “sand” at the right pressure.

Cheers
Greg
Sandgroper

Hi Greg,

Tyre width can be discussed and postulated upon until the cows come home.
However you cannot refute the basic physics relating to the pressure resulting from a force supported by an area. Therefore the support offered by a tyre is directly proportional to its contact area which is length x width in contact with the ground.

Where the observations can fail is the apparent increase in width with deflation which is primarily the sidewall bulge offering little or no support in the contact area. However a wider tread area must give more support than a narrower one, deflated or not. It is fundamental. This is not to say that it provides better traction, that is a more complex subject.

Hi

Sorry, that’s what I thought we are talking about ..."traction". Wasn’t refuting that a wider tyre may have more support when parked up – but things change when you apply drive to the tyre and this fact then becomes irrelevant. The theory behind it all is of no consequence - my opinion of the subject has been substantiated by extensive "field trials". I have never had any problems with vehicles using "narrow/skinny" (whatever these terms actually mean) tyres in sand (e.g. standard hilux road grippers are fine).

When driving on “soft sand” you are almost always obliged to reduce tyre pressures from standard road pressures irrespective of how wide your tyres are. If there is any advantage with "wide" tyres with respect to traction on sand it is too small to measure/notice. If there is an advantage how come you still need to let your tyres down? If you put ”wide” tyres on your car and they are better than the “skinny” tyres you had previously ..it is not because they are wider it is because of some other inherent characteristic of the tyre you are choosing to ignore (e.g. larger rolling diametre = longer footprint).

My understanding of the subject is that the length of footprint is most critical (for sand) as that is the direction of drive force - the more sand you are contact with in the forward back direction, the more friction exists between sand grains in this direction… this is how the increase traction is obtained...and less chance of tyre spinning. IMPORTANT FACT: This friction threshold is easily reached with “skinny” tyres by reduced air pressure. Any advantage a wider tyre may have in this respect (because it is wider) does not contribute enough (if any) to this requirement and therefore width makes so significant difference in capabilities with respect to traction on sand.

Anyway – again – bottom line – don’t forget to wave when you see me drive past you on the sand while you are letting your wide tyres down…just like we all have to :)

Cheers
Greg

No Greg, we were actually discussing track damage.

Your:...."The theory behind it all is of no consequence...." In other words, do not confuse me with facts, my mind is made up. Anyway, I was not spouting theory, I was expressing long-established physics.

Your dissertation makes several expressions but none are supported by established scientific facts. They are purely empirical opinion and may or may not be correct.

This "Length" of footprint is frequently touted as being the significant element whereas it is actually the significant result of lowering tyre pressure rather than any width increase. So the footprint area increases, but it would equally increase if you were able to widen the footprint by a similar amount.

Be quite clear, I am NOT saying that lowering tyre pressure increases the width of the footprint, but I am saying that if you CAN increase the width then you also increase the footprint and therefore the flotation which is essential to avoid terrain damage.

If width played little or no part in flotation then why do they manufacture tyres such as these?

Hi

More traction = less wheel spin = less track damage...or have I got it wrong? Is this what they call semantics? Apologies if my experience in driving in sand doesn’t qualify as being worthy of mention - and yes my mind is made up. Wasnt try to pass off my comments as proven scientifc fact, just my attempt to explain why skinny tyres are fine..if I have the explantion bit wrong it doesnt change the fact that you can drive around on sand with skinny tyres. You will have trouble convincing me that "narrow" tyres don’t work as well as "wide" tyres in sand at reduced pressures (Ive done it - thats a scientific fact :) and are therefore are not suitable for driving in the Simpson or any other sandy place (because they may cause track damage or you’ll get bogged).

If the tyres are not spinning they are not spinning...i.e. no track damage..the threshold for adequate traction is easy reached with skinny tyres and wide tyres by reducing tyre pressure. (I am talking about currently available tyres generally used by the 4WD fraternity for currently available 4WD vehicles...not push bike tyres on a 200 series or moon buggie tyres on a Vitara)

No real idea why they make that tyre or for what application. Figure they are designed to reduce pressure at any one point to reduce damage e.g. golf green/lawn or prevent sinking e.g. swampy ground - they don’t appear to be a sand tyre. If it is for a 4WD to increase is ability in sand they would have been better off fitting a set of these:




:)

See you in the dunes with my skinny tyres while at the same time doing no extra track damage :)

Cheers
Greg

Hi again ..just a thought - what do you (or others) consider to be a "wide" tyre and what is a "skinny" tyre?

What minimium tyre width (again sticking to real world applications for existing vehicles/tyres) would result in "track damage" irrespective of tyre pressure?

Cheers
Greg

........"yes my mind is made up."

OK, I won't waste any more of my time then.

"........"yes my mind is made up."

Ive driven around in sand with skinny tyres including up dunes 5 x bigger than Big Red.. no problems - how can my mind not be made up - was I dreaming? If my attempt to expalin why I could do this (sand grain friction in direction of drive force/long tyre footprint blah blah) is incorrect I have happy to be corrected on this matter....but it doesnt change the fact that you can drive around on sand with "skinny" tyres by reducing pressure..and not cause any more track damage compared to someone with wider tyres (who still has to reduce tyre pressure as well ..and if they dont will cause "track damage".) Width of tyre doesnt matter (4WD sand driving application) - its the pressure...my mind is indeed made up on this matter and if you were in fact trying to alter it, good choice to bail out.

No harm done - happy travels.

Cheers
Greg

For once I am laughing. I usually get hung up in one of these, shall we say, "discussions. And this time it isn't me. I am not laughing at you guys just at the relief I feel that it isn't me.

Have a good day.

Phil

Good to see it had some value..

Enough of this ..back to work..got to save up for some wide tyres (and maybe some physics lessons).

Cheers
Greg.

Hi Greg

I actually seen a show on tv many years ago that supports you experiences.

It was when wide tyres were just starting to get popular and they were measuring the actual contact area.
It was shown that when pressure is reduced your normal split rim type tyres had a larger contact area than wider tyres with reduced pressure.
If I remember correctly it was due to the side wall on the wider radials bulgied but the tread length did not increase, whereas the split rim tyres would lengthen the tread instead of bulging which gave a larger footprint.

Chris

Thanks Stephen,

Its good to get some honest feedback and head out there prepared!!

Cheers
Bluey

I meant to ad we have the 4.2TD auto LC.

A few photos and panoramas here:
Trip photo Flinders NT, Simpson, Chambers and Lambert Center

Flowers:
Flowers of the desert

Camping:

Hi Phil

Looks like you had a great, I checked out your photos!! Thanks for the tips and pointers above, they all make sense and I will use then as I get organised.

Cheers
Bluey

The best time was in the evening beside the fire after supper with a good cuppa and stars you would not believe. Enjoy!!

It's not hard just needs good preparation, some common sense and a respect for being remote.

Phil

I agree with PJR but the speed can vary between 20 - 40 kms depending on your mood and the conditions. Each to their own. Keep that fishing rod and red flag hoisted high... The French Line can get pretty busy. Other routes are more of a personal experience.

WE followed the WAA line then down to Lone Gum and up to the French and then of course the QAA out to Birdsville. Only because it is less travelled and was supposed to be the hardeset. We saw one car in the first two days and then after Lone Gum about 6 plus a dozen bikes until Big Red where the "crowds" were. Didn't bother with Big Red.

The only times we were over 20K were the few salt flats and a couple of inter dune spots. The road was smooth but up and down over heaps of "speed bump like" large undulations. ALL the way. I would consider that you may do what we did in three days.

Make sure your shock absorbers don't overheat and break down. It was a real roller coaster. Our Bilsteins were bloody hot and rested at least twice a day. Its hard work for them. Worse that corrugations with the big movement they have to endure.

If you wish to change then consider what a bloke who does a lot of recoveries in the Simpson uses. He has Old man Emu nitro shock sports. And completely satisfied with them. We are moving to them if the Bilsteins break. That's if they do.

Phil

PJR

What were you driving that weighed 4 ton ??
how does your insurance stand up in an accident???

Geoff

I said "almost". It could be around 3800Kg I have not weighed it as I prefer not to know and hope I do not get stubng. I would also guess that most self sufficient 4WD's (Patrols/LCs) that are not tied to a van or trailer etc are also ove. So I heard the other day when we were looking at yupping the GVM.

I also added the wood we took from home at 80KG. It all adds up Geoff.

It's a 100 series 4.2TD.

Whether it's a stock LC or mine it really doesn't change the message in this thread so I wonder why you asked?

You may want a compressor so you can pump up tyres later, an extra spare (in case) and if you want some creature comforts, a fridge (for cold water of course) which would then require a spare battery - or a good esky with solid ice blocks as we did on our first simpson trip 15 yrs ago (when you only saw 2 cars / day - those were the days).

Otherwsie LC will walk it in (don't forget a spade for my type of moments changing mind on direction mid dune).

This post has been read by the moderation team and has been moderated due to a breach of The Personal Attacks Rule .

Forum Moderation Team

Thanks Guys

I have a nice compressor based on 4WD Action review and it seems to work well for the size and price and will definitely take my shovel and the recovery gear.

Cheers
Bluey

looks like you read it too. K1 line is definitely worth a look. Our favorite part.

You might be right Peter

But with Murphy's Law around one corner somewhere in Australia I won't know till I have done it.

Cheers
Bluey
Ps I like you sense of humour, dryer than the Simo I expect

Many thanks.

Cheers Bluey

Very true 2517. But 1 jerry can if you want to detour and follow the K1 and go up and down Big Red 10 times at speed. You can empty your jerry can into your tank on the 1 st day and stick it on your roof and have that extra peace of mind.

Bluey

In the future you may find it worthwhile, maybe not a financial benefit though, but worthwhile to invest in a long range fuel tank. We have one that carries 125 litres of diesel and 55 litres of water. The water is pumped up as required to the rear of the drawers in the back. Of course to a nice chromed water faucet. Why not a bit of "bling"!!

No worries on any trip about fuel. We also take water from home and after the Simpson Desert we still had 5 litres of "home" water in it. No worries about "Bali belly" from "other" water. I have cancer for which the chemo stuffed my immune system. It is weak so I have to be careful. But it is a bonus drinking ones "normal" water. Good for our Canning trip soon. For the Simpson we filled up at My Dare and then could have made it to Marree via Birdsville and the desert if we wished. But we do top up occasionally. Then a top up in Broken Hill which got us comfortable home to Canberra.

Losing the spare tyre underneath is a concern. But touch wood the singlwe spare on the back will do. Last flat was 40 years ago so "touch wood" the single on the rear carrier will do.

Phil

Sounds like a nice set up Phil, and one I will look into long term. All the best in beating your cancer mate, and enjoy your trip down the CSR!!

Cheers
Bluey

On another note, be wary of lifting your cruiser just now as there may be an issue with the CV's once lifted - I am following a thread on another forum with keen interest on this subject.

G'Day Colin

Thanks for the reassurance and the tips, I have taken note and yes it will be my first time out there!

I will go cautiously on the lift, its not in the budget for now and I will do more research if that changes. Thanks for the heads up.

Cheers
Bluey

I believe a 2 " lift is only around $500 fitted (eg Terrain Tamer) new heavy duty springs and trouble -free running. Still comfortable carrying a load or not. Never bottom out.

Bluey

You won't need a lift for the Simpson.

Phil

Thanks Gents

Thanks RobA. Stock it will be.

Cheers
Bluey

Good to know MM. I shall go for it.
Cheers
Bluey

Thanks Rainbowprof, it sounds like you have quite a driveway!! I will definitely take the wipes, nothing like a simple shower while camping.

Cheers
Bluey

Many thanks Dave,

Yes I was planning on playing it safe with a couple of jerry cans and I hope the tyres will make it through!!

Cheers
Michael