I used an old MXer trick, I mixed ATF with 50 weight oil 50/50. The ATF prevents foaming and the 50 weight, well, it does what 50 weight does! Lol! Haven't ridden it yet but they already feel stiffer. Of course it's still rather cool(40s) around here.

 

if the front end sags an inch from full extension with rider, thats about right. look in the manual to see what your preload sag is supposed to be. i think its around 30mm, which is just over an inch. any more than that, you will need to put in spacers to set the preload or replace the springs with stiffer ones for your weight. checking/changing/upgrading you fork oil is a good thing to do anyway.