I agree with Fletcher on PSI and application, 5 to 6 is a good starting point, that being said,
It absolutely depends on the tire, I haven't wheeled the MTR's, but with the weight (or lack thereof) of the Zuki, 4 to 8 depending on the trail is probably where you will be.
I have seen stiffy boggers run at ZERO pressure, no beadlocks, no problems.
I have seen wanna be tires like AT's roll off the rim at 10psi
I run my LTB's, NO BEADLOCKS at anywhere from 2-8 psi with absolutely NO problems
Just experiment, with Beadlocks, you can run from zero to six easily, but you get to a point of diminishing returns... you have to experiment, many factors come into play, Flexibility of the tire, age of the tire, driving style, etc...
A good starting point is 5 psi, and adjust from there. You want the tire to conform to the rocks, without giving TOO much lateral movement when sidehilling.
One small thing I sort of disagree with.... I feel that less pressure is good for sharper rocks, and I tend to run the same low pressure with smooth rock, as I do with sharper rocks. I could be wrong, but it seems that a lower pressure will allow the tread (or sidewall) to deflect, instead of being penetrated by a sharp edged rock. The thing that might be different is that the sidewall "squat" could possibly allow contact with sharp rocks that otherwise would not touch with higher pressures... that may be the point there... but with the low weight of these vehicles, you will get less squat with those MTRs at 6 psi than you might think..
uh... yeah... too many words...
uh...hum.. try 5 or 6 psi and tell us what you think.
