Depends on Frame STA, and Your Femur length, etc.

I got a Bike, Koga WTR, with a Zero set back Airwings tour seat post
and, now like the Cane Creek Thudbuster seat post with set back Better ..

short adjustment rails of the B17 that was on the bike made it worse
so the saddle went first, then the Post.
Added the illusion of a lower STA, by using a 180 arm crankset (I'm Not a Spinner)
saddle further behind the pedal at 3:00, the downstroke.

You can get seat posts in diameters that match your frame , from like Thomson in the right size .


./.