[quote=Autostream]OK, so I'm not about to have 5 sets of wheels, but may have to look at making my stockers bullet proof.
I lower the pressures significantly, but I suspect that because the tires are rolled in so much for the narrow rim that the sidewalls are not flexing as much as they could/should, particularly with a strong tires like the Dunlop D908 RR...would this also be a correct observation?

exactly,,,,if the tires are too stiff,they will not round out to get the proper profile for spreading the load better,,hence they just drop down and bury themselves,,,REMEMBER the key notion is FLOTATATION when it comes todealing with sand
there are several great tech articles that i read years ago showing the dynamics of what transpires in sandy circumstances
so getting a large soft foorprint is what we are after
QUESTION:
If I was to bring my stock wheels over in September (be in USA for 4 weeks) what rims would you recomend for travelling outback Australia and sand?

if ya spend more time in the sand then the hard pack then i think the oem rim sizes sound good to me,,,,we can improve a bit on the strength and durability of your wheel ,,possibly go with 4.25x18 Sun/Excel rims ,,lighter and strong without the crazy big tire bead of the oem Behrs....which BTW are a major pain in the butt to break the bead on on your stock oem Behrs
if ya spend 50 -50 time on road and dirt then 3.50x18 is your better bet and to reiterate,,,the hot set-up for mostly trail/dirt riding is 2.50/2.75 x18
Here's a good example of conditions...
http://www.advrider.com/forums/showthread.php?t=152387 but maybe with a little more sand.

i just love those conditions,,,billabongs n all
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