Bill, my Haynes manual No. 3466 BMW R850 & 1100 4 valve twins, has an electrical diagram section at the rear of the book.
It's in colour and is in sections, as in frame circuits, engine circuits etc, etc.
It's not the greatest but as a bonus it tells you how to do nearly anything except how to pull the gearbox apart and things of that ilk.
Mick.
Ps:- buy the hard back version, lasts through heaps of services and bending by greasy fingers far better than the soft cover version.