Its coolant. From the weep hole on the left side of the engine, runs down the stator cover and drips to the floor. While the bike is moving, the coolant flows along the casing and down to the exhaust.
I'm pretty sure you'll find some dried coolant near the water pump weep hole, so I'd take it back to the dealership to have them check it (free of course). If anything, you'll be getting it on record that there's a coolant leak in the event that the water pump fails even more - warranty has covered some of the users on here for a new water pump.
As far as cleaning it goes, I haven't really been able to take it off myself. Baked coolant on the exhaust can shields apparently come off with warm water and paper towels or dish soap + water or some other solvents (ie. WD40, brake cleaner), but I haven't had much success. I just try and wipe it everytime I wash my bike and hopefully it goes away with time.
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