For three months storage all you'd need to really do is leave it on a battery tender. No harm in changing the oil though before you're riding again.
I had my GenII off the road for 16 months. All I did was keep the battery charged, changed the oil every 6 months, did full fluids and filter at 12 months and started it up for 20/30min every other week. Fuel and oil should be good for around 6 months before it starts going off, but make sure your battery is charged up.
If you can cycle through the gears on a stand etc.. it would be of benefit, as I did have my clutch play up a little bit,
but even then it wasn't until around the 8 to 10 month mark.
I had my GenII off the road for 16 months. All I did was keep the battery charged, changed the oil every 6 months, did full fluids and filter at 12 months and started it up for 20/30min every other week. Fuel and oil should be good for around 6 months before it starts going off, but make sure your battery is charged up.
If you can cycle through the gears on a stand etc.. it would be of benefit, as I did have my clutch play up a little bit,
but even then it wasn't until around the 8 to 10 month mark.