Perhaps someone has put some radweld or similar in the expansion tank in an attempt to fix the weep from the radiator.
Whatever, take it back and insist on an xt660 as a service bike while they replace the rad under warranty and flush and replace the coolant. While you have the service bike try and do thousands of miles on it.
Good luck with this. It's a right ball ache when a new bike goes wrong and you are dealing with a bull****ting dealer.
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