You know what would fix the water in oil issue?
NOT LEAVING THE QUAD OUT IN A FUCKING STORM!
Thats why you had water in the oil.
Or an airbox lid without a hole in it.
design/tell us what to do for a nitrous set up for Chris and I'll get one too.
There really isn't much to tell, they make the kits with everything you need to get N2O and extra fuel into the motor. And from there you can get bottle warmers, purge kits, window switches, etc if you feel the need.
X2 there is no way water should be getting in I dont even think the airbox is the issue I ran my 400 ex with out a lid and I never had that problem.
It is 100% the issue. Water can run under the seat right to the open lid. The PCV is ran into the airbox low, so it only take a little bit of water to get to the crank case. Not to mention air filters are supposed to be dry.