ok here's a basic rule about kawasaki engines.
If it is a gpx or uses the same engine, it
will have clutch noise, this is a fact. Depending on the individual bike it may have it only when cold and first starting (my el250 demonstrated this) or may be when warm too.
some do it with the clutch engaged, some with it disengaged, some both. mine did it wiith both at very low revs at cold.
The noise im referring to sounds like a deep clunk clunk clunk that sounds like its doing it once per revolution. Sorta similar to the clatter of a dry clutch system (ever heard a ducati or a guzzi?)
If it's only started doing this (as opposed to 'always' having it) the first thing i'd suggest is an oil change if you didn't just do one as these motors are super narky about their oil changes being every 4000km maximum, 3000km preferred. and then if the noise continues get it checked by a mechanic.
But from general experience a clutch noise not accompanied by unusual behaviour such as clutch slip or burnt oil/eating lots of oil = nothing to be worried about, just be mindful of
