Try distilled water...it's free of dissolved minerals thus won't leave spots, especially on a hot or warm engine. Works like a charm. You can get it at any food mart or grocery store for about .80 cents.
"A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort."
2014 CVO Road King (FLHRSE)
Titanium Dust and Galactic Black
2015 Freewheeler (FLRT) for the little lady
2012 Switchback (FLD) sold the POS
2008 Heritage Softail Classic (FLSTC)