I use automotive car wash solution. I believe I got the gallon jug of it at Costco. It's cheap and easy to use. It cleans well and rinses spot free. The brand is Meguire's. It won't hurt anything on the bike either, and I don't think it would be detrimental to the flat paint on the SE model. I usually just rinse the bike with the garden hose, then use a soft terry cloth towel to wash off the painted parts of the bike, and a soft bristle car washing brush for the engine. I don't use it for anything else. Then rinse again and dry off with a clean towel. What I never do is direct a strong stream of water directly to the ends of the wheel axles or any of the electronic components. I know the bike is designed to be operated in all kinds of weather, including the rain, but there's just no point in inviting disaster.
"Don't sweat the small stuff---it's all small stuff"
'09 650 VStrom