What exactly is the problem you are having?
I had removed the decompressioner all together in my Honda 400ex as it went bad and was making noise, Also on the HotCams for the 400ex the decompressioner is not used. I am sure this is the same for the 700xx but I have not had mine long enough to really have any problems with it yet.
As for the Kibbelwhite valves & springs, I have them in my Yamaha Warrior 350 and they work well for me.
2008 700XX - OMF Beadlocks w/Billet Centers & Reinforcement Rings, Kenda Kutters, CCP Steering Stabilizer, ASV F3 Levers, ODI Rouge lock-on grips, Houser Bounce Nerf Bars, Pro Armor skid pad, UNI Filter
2007 400EX - CCP Steering Stabilizer, GT Thunder 450R Shocks, 450R Rear Brake Conversion, YFZ450 Front Brake Conversion, ProTaper Bars, Rath Racing Nerf Bars, Alba Elite Bumper, ASV F3 Levers, ODI Rouge lock-on grips, UNI Filter, Kenda Kutters, Pro Armor skid pad, Armadillo Swing Arm skid pad