DF250RTB 2012.

I have a question and no one has been able to answer it.. I have checked the bike and unable to locate the source:
The Problem:
I get a slight oil leak when my DF250RTB on the kickstand, it's a very slow leak. I put a newspaper below the leak.. But if I don't ride for a while the all the slow leak
dripping shows..

Where could the leak come from " could it be the gear seal or chain drive gears... any ideas..


Thanks..

I hope this not in the wrong area..