Generally speaking Zs are heavier but that body and neck wood make up the main concentration of the weight.
I’ve played a fully loaded Z3 6 with a lighter weight ash body and a maple neck that was barely over 8 lbs (Jared smiths bass). I was shocked how light it was compared to mine.
Of course we are also talking about 6 string basses too so the added mass of the wider neck, heavier pick ups and more hardware comes to play.
both of my newer Zs are 10lb basses for sure. My old maple and alder voodoo is a heavy 8 IIRC and my previous Ash/ Maple was a nice 8 lbs.
That said, in regards to the neck wood, @MascisMan , I agree the wenge neck is amazballs, however, depending on your tonal preferences and such there may be a better and conveniently a lighter option for you.
For something brighter and snappier the roasted ash maybe a superb option, or for a more mid open content maple is still tha bomb. Perhaps Ovangkol for something a bit more sultry and woody?!?
Wenge… articulate, focussed, punchy.
options for sure.