Im only a bout 140lbs and my MZ Comp fork seems pretty stiff to me. I have the knobs on the top turned to the lightest setting, but i still dont feel like im getting near the full 100mm travel i should. i don't know much about fork adjustment, but is there another way to lighten the tension? there are 2 knobs on the top, are they both the same thing?

Marzocchi MZ Comp... Is that an MCU/oil fork, if my google search is correct. You should either be able to get a lighter weight MCU from Marzochhi or perhaps aftermarket or change the oil to a lighter weight oil (or both, but preferrable one at a time). The MCU might be a good start, but do realize that the cold weather (It should be cold in OK) will tend to freeze MCUs which make them harder than normal so if you're riding now, the stiffness might be due primarily to the weather. But keep that in mind that you can change out the MCU and oil in your fork. I'm even lighter than you at 130lbs and when I had my old Proflex Beast (Girvin Vector fork), I changed the oil to a lighter weight and that helped a bit.

Jay

Change the springs and the weight of the oil.

is that something i can do myself or would i have to send it in?

Stiffness is not a bad thing, providing you can get the full travel. I take it they are new forks, so will need a certain amount of time to "Run-in" I want the other way, and have the heaviest quality springs in my Marzocchi Freerides, and still it feels like a pogo stick. (It's on the tandem by the way) To assist in this I raise the amount of oil used in the forks, and go to the heavier oils that are available. Have you checked that the forks are not overfilled with oil? as this will cut the amount of travell available, and also to a certain extent stiffen the spring.