From what I have heard it takes all the bike can generate to run the lights, horn etc. but when I brought this up before no one responded. I had hoped there was someone knowledgeable enough to determine if I could use an electric vest that drew 47W. Surely someone out there knows how to figure this out.
Leonard,
Not sure that I qualify as "knowledgeable enough" but I'll give it a try.
I believe the stock alternator on the electric start models is rated at 116W (someone correct me if this is wrong).
If you are using say a 60W headlamp, a 10W tail lamp plus a couple of 2W instrument lamps plus a couple of watts for the ignition you would be drawing 76W continuously plus brake lights, horn, starter, etc. intermittantly.
116 - 76 = 40W
In short, no, there is not 47W to spare.
Hope this helps.
Andy