Saturday, Jan 14, 2012 at 09:38
Speaking of tyre pressures...has anybody seen the "advert" on commercial tv done by
Spider Everett for a show called :Great Australian Doorstep"? He has been featuring a series of advice for would-be outback drivers. One of these snippets of advice is to INCREASE your tyre pressures on gravel roads.
Needless to say I wanted to set them straight and the following is my email to them:
QUOTE:
G'day there,
You're currently running an advert for off-roading tips. One of the tips is to pump your tyres UP when going on gravel roads.
I strenuously urge you to pull that segment and do some PROPER research into the relationship between tyre pressures and gravel roads.
I think you will quickly find that the accepted method of tackling gravel roads is to REDUCE your tyre pressures.....the rougher the track the more you need to reduce them. But, you also need to reduce your speed commensurately.
The rationale behind this makes perfect sense once you stop and think about it.
Imagine, for a moment, a fully inflated balloon being pressed against a sharp object.....it would "pop" quite quickly with very little pressure being applied. However, if the balloon was only partially inflated, it would withstand much more pressure before it would "pop".
The same applies to tyres: When a fully inflated (or "over-inflated" if your previous advice is followed) tyre is used on a gravel road, then every
rock the tyres pass over will be like that sharp object that was poking the balloon.....eventually your tyre/s will pass over a
rock with a sharpish point and you'll suffer a puncture/blow-out. However, if you REDUCE your tyre pressures from, say, 40psi (highway pressure), to say 30psi, the tyre will have a better chance of survival because it can sort of "mould" itself over the sharp rocks.
One very strong proponent of this method is a bloke named Adam Plate, the proprietor of the
Pink Roadhouse at
Oodnadatta, in the SA outback. Adam has changed more flat tyres than most of us have had hot breakfasts!! He has drawn-up a hand-written sheet of suggested tyre pressures for the various sorts of vehicles that are likely to frequent the outback. He provides one of these sheets to anyone who visits his establishment.....most of whom are there to have a coffee and a feed while they wait for him to fix punctures which have occurred because they have had TOO MUCH air in their tyres.
You people have a duty of care to ensure you publish CORRECT info for all those "numpties" who have got "all the gear and no idea"... (my terminology for city dwellers who have gone and bought all the flash gear, but have no idea how to use it).
I have done numerous outback trips. Following the above "system", I have never suffered a
puncture on a gravel road. It is amazing how often you stop to assist a fellow traveller with a
puncture....the conversation almost always goes as follows:
Me: "Mate, what sort of pressures are you running in those tyres".... Him: "Yeh, I don't understand why I had a flat, I stopped and pumped some more air in when we got to the gravel...I'm running 50psi"!!!
Unbelievable!!!!
UNQUOTE
Cheers
Roachie
AnswerID:
474884
Follow Up By: Member - Phil G (SA) - Saturday, Jan 14, 2012 at 21:05
Saturday, Jan 14, 2012 at 21:05
Gday Roachie,
Hope you and the family had a good Xmas,
Yeah, they like to recommend high pressures - the reason is that the tyre can't be blamed and it reduces warranty claims. If your pressures are high, you'll get tread punctures - that's a problem for the vehicle owner. If your pressures are low, you can delaminate the sidewalls - thats potentially a warranty claim.
Same deal with rent-a-cars - they all pump the pressures up.
FollowupID:
749901