I've got the mudlite xtr max is 7psi "i beleave" and I run 5psi in the front and rear. My buddy has the mudlite XL's and runs 6psi in the front and rear. Its kinda a trial and error thing as to what you like, just don't go to low or you can de-bead the tire when its in a bind or push stuff between the rim and tire bead which would cause a slow leak.
2007 Brute Force 650 SRA, HL springs, Jetted, UPP intake,VFJ clutch and prim/secondary springs, HMF full sys, Dynatek, 28in Zillas on SS108 14in rims, 2.5in intake & 2in cvt Snorkles, Rad Relocated to rack
"I thought an ATV was going to be cheaper than building another mud truck, haha"