how slow is slow enough?

Hmmmm..Common Sense....have you seen any lately?....LOL


Cheers

Everytime I look in the mirror.
Its sadly lacking anywhere else though :)

I thought that it was generally regarded that 4 wheel drive operators were over-endowed with consideration and heaps of common sense. William, are you seriously suggesting otherwise.

Sure, troopyman, you get a lot of stakes on the Birdsville Track! (and how much bulge do you get with LT ATRs at 26psi?
That wise man says many things, often before he thinks.
Chris (SA).

I just found this in the archive and thought it made a lot of sense:
S&N replied:
what is the "pressure/speed/load equation"? is this an actual equasion or just experience?
Reply 8 of 10
FollowupID: 437522 Submitted: Friday, Jun 30, 2006 at 10:19
Robin posted:
Hi S&N

There is an equation, but as technical details of commercial tyres are kept out of the glossary ads it is effectivily empirical from our point of view.

I think its pretty well universally excepted now that on roads like Birdsville track which have lots of stones , there are two prinicpal factors that lead to tyre loss. One being fracure of tyre by hitting a stone to hard , and the second being heat build up.

Lower tyre pressure reducing fractures but increasing heat , and speed increasing likely hood of either failure.

So to go faster you need to increase pressure to avoid fractures but increasingly move into the likely hood of failure via heat build up.

The question being , what is best combination. Here I guess with lack of information it becomes experience based.

Starting point being a little lower pressure than normal for your load and dropping speed back to around 80 to compenstate for more heat from lower pressure.

Not doing both , increases the likehood of failure , if your car is overloaded/lack of suspension travel /or tyres not so good travel then you need to go lower/slower again than the rest of the mob.

In this trip the 60 series due to suspension and loading was likely to break first.

One tyre shredded first , then the others were pumped up a bit more then a second failed soon after.

Unfortunately I wasn't on the spot , and don't know if a judgement could be made as to failure mechanism

Robin Miller