I seem to be suffering this mystery ES front end rattle as well on the 2018 matte blue bike.
Mortenk has accurately described this clucking sound. It is particularly noticeable over small bumps, driveway lips, small potholes, etc.
I am hard-pressed to think a factory new bike with less than 1000 miles on it suffers from loose steering stem bearings, but damn if the symptoms don't line up almost perfectly.
I want to disassemble the handlebars/triple tree like I want a hole in my head, so I need to exhaust all these other possibilities here first.
I know it's not the two forward fuel tank bolts.
I don't think it's the calipers - but I'll give them a good look anyway.
Back in the Day, we use to be able to remove the triple tree and leave the handlebars in place. Not so sure this is the case on modern-day ES bikes, since they have a wire harness connected at the tops of the forks - what an ass pain this will be, if I have to actually adjust steering head bearings.
So I am hoping I find it is something else.