Transmission gear breakage (recall 18V-089)
Kawasaki recalled 2016–2018 bikes because transmission gears can break during a hard or missed shift, which can lock the rear wheel. Dealers replaced the 2nd, 3rd and 4th output gears and 2nd input gear free — ask for proof the recall (MC18-01) was done. On the test ride, shift firmly through every gear; false neutrals or popping out of gear mean the box may already be damaged, and that repair means splitting the engine cases.
Ask for repair records covering this item. If it hasn't been addressed and the car is in or near the mileage window, price the up to $3,000 repair into your offer — or make it the seller's problem.