What pressure for 27" Mud Lites

I run mine at 4 psi mostly, but thats just durning the winter. During the Summer I get them up to there max at 7 psi

7 lbs. is a little hard (in my opinion). Start out with 6 or 7 lbs and work your way down to 4 lbs. See what the different preasures feel like with the type of riding you do.
You want your contact patch to be the full width of the tire. If you do a lot of mud, sand and rock riding, you want less preasure. If you ride mostly hard trails, you can go with a little more preasure.

I'm happy with how I run it. I've got 1000 miels on these Mudlites. I keep them aired up because I ride the river alot and I want the tires as tall as possible, better flotation as well.

I've found running my tires at 4 psi I get really good flotation on top of the snow during the winter. the nice thing about having 12" tires all around, these babies get me up on top of the snow as long as I can keep the rpms up. Its a cool thing to see.