It this normal sound from kz550 ltd?

Hi im new about kz 550 what problem can be in my kz 550 ltd. ? 50.000 km 1982

Without the airbox connected it will need rejetting to run properly.

To make sure all cylinders are firing at idle, you can spray a little water on the header pipes from a small spray bottle.

To me it sounds out of sync and maybe one cylinder not firing at idle.

With no airbox is will run poorly. Install the airbox with filter - then see how it runs. Ed