I also have an '09 Stella, but have not had any problems like that because it does not rain in my state, at least not in the part of it where I live. Ask on stellaspeed.com. Something somewhere is grounding out when it gets wet.
I won't spend more on a bike than I think it's worth, but if it's a good deal, I don't seem to have a problem buying bikes I don't need.
2002 Vulcan 750, 2013 Royal Enfield B5
2001 XT225, 2009 Genuine Stella
1980 Puch moped