The manual recommends kayaba 01 fork oil ( i believe its 3-5 wt, but I'm not for sure). The adjustable range is 45-95mm. Remember this is with the forks fully compressed, without the springs. You measure from the top of the forktube to the oil. Some company's sells a tool to measure oil level(racetech and motion pro have it for sure) Also if you dont have a service manual(good stuff), www.themotorbookstore.com has one for $20.96 plus $7.00 for shipping(thats where I got mine) If you call your local dealer they should be able to tell you the the exact oil weight, and the adjustable oil range(or capacity) for your forks.
In my experence the forks work best with the Kayaba 01, though 5wt will work. You can use a turky baster and pice of rubber hose to set the level if you like, just be sure to measure it correctly, as described above.