I just got a second hand 2016 250L. It was in immaculate condition and only had 98 miles on it. While riding it around it started to loose coolant at an alarming rate all over the left side of the engine, as well as the inner faring and even some onto the upper left side of the gas tank. I originally thought that maybe the overflow had decided to let go of some coolant while the bike was getting used for the first time. But while inspecting it today the overheat light came on and it is still leaking coolant while running. The bike currently has 190 miles on it. Any help would be greatly appreciated. Here is a picture of the coolant on the side of the engine. https://imgur.com/a/fMenb
I can only suggest you clean it up pretty well and then run the motor with the bike stationary to identify where the fluid is leaking from, then post back to the forum. I would imagine that your warranty is still valid but only a honda dealer could confirm that.
Start with the easy to see stuff - worm gear clamps on the hoses, the hoses, the gasket on the water pump, then the radiator. It might not be as bad as it looks as the air flow shoots stuff around pretty well under there.