I'm wondering how long i can leave my bike alone without doing any storage prep? ie, how many days (roughly) b4 the battery dies and oil settles too much(?) etc without moving the bike or starting it up?
well, you can go as long as you want to try to push it. i left my bike alone after just changing the oil for around 2.5 months at its longest, and it came back alive when i pulled it back out. however, there's really no reason not to take some precautions if you're storing it for a while. changing oil is a quick, cheap, 30 minute job. and then you just need to pour some stabil in the tank, put some more air in the tires, and pull the battery out. all stuff that's really easy to do, and in my opinion, better than hedging your bets only to come back and find out you have some more problems to deal with.
would taking the bike out once a month for a spin be good enough not to have to do the storage prep?
like i said, it's all in what you want to wager. however, i'd bet that once a month, on a decent little ride should keep it in check.