What precautions, if any, need to be taken before standing the Rincon on its rear. Does the battery need to be removed and will any of the fluids leak?e.g. coolant, fuel (even if its turned off), etc.,.
Turn the fuel off of course. If your gas tank is over half full then fuel will leak out of the vent hose @ your gas cap. I clamp it with a pair of vise grips before I stand it up. Nothing else to worry about.
Another thing you might want to do is to get a friend to help lift it. after you get it about a foot off the ground it gets heavy. I have a hook point in the header over the garage door that I just hook the winch to and simply push the button. It saves on the back. and riding sucks when your back hurts.
Dont forget the gas vent like hondaman said. I stood mine up to put on a skid plate and didn't realize it until I heard the gas dripping! Took me a minute to figure what was leaking! Filled the steering stem up and soaked the seat!
There's really nothing to worry about except personal injury. I've flipped my bike completely and stood it up a number of times. If you have the rear rack extension, it actually acts like a wheelie bar.
If you're standing it up on the rear rack to wash underneath, turn off the fuel, clamp the fuel cap breather hose, and make sure to turn the water pump drain hose to the side or something so you don't spray water up in there. The easiest way I've found to get it on the rear rack is to pop a wheelie in the yard like BDMB's pic and hold it there. (If I'm alone anyways)