82 KZ305 engine swap

I am considering swapping the blown engine in my chain drive KZ305 with a belt drive engine.
Is the counter shaft the same on belt and chain drive, so it will be just a matter of replacing the belt sprocket with a chain sprocket?

Cool project!

Unfortunately the output shafts have different part numbers: 13128-1036 for the belt vs 13128-1032 for the chain.

www.partzilla.com/catalog/kawasaki/motor...z305-a2/transmission
www.partzilla.com/catalog/kawasaki/motor...z305-b1/transmission

However... There appears to be a threaded part on the belt countershaft that's not on the chain-drive version. It's difficult to be sure using just the Partzilla drawings but if you can remove that threaded end you might be all right.

Looks maybe like the sprocket and retainer may fit on the belt shaft with the threaded end not interfering? Again, hard to tell from the parts diagram...
but worth a try.

I don't remember exactly what all I did when I converted mine 15 years ago, but it was easy-peasy andf I had pretty much zero bike experience. You'll need an offset countersprocket or spacers, I want to say 7mm but do not trust that number. I don't remember doing anything special up front other than that.