The carburetor style is correct. I agree it is not genuine Kawasaki as the numbers would be as pictured below. So, who know what jetting this carburetor has. That could be an issue. What do your spark plugs look like after running in this condition? Are they black with dry soot?
You had the carburetor apart. Did you install new o-rings upon reassembly? If the o-rings are leaking internally the engine will run rich. Specifically, the o-ring at the bottom of the plastic spacer where it meets the float bowl and the two other o-rings on the top. One is round to seal the float valve seat and the other is butterfly shaped. Also you will want to pay attention to the air bleeds to make sure they are clear. The air bleeds are two of the smaller holes on the choke side of the carburetor, you will see brass jets pressed in. They are not intended to be removed but with the top plate off, you can clearly see light through them if not plugged. The larger holes are bowl vents. If they are not clear the engine will run rich. The main jets are pressed into the plastic spacer should have a size stamped in them. Might need a magnifying glass to read. To get at them you can use a drill bit and press then in and out. Just make sure you use a drill bit large enough as to not bugger up the metering hole size. The jets also have o-rings installed.
