saddle geometry

[metropical75]

got a new saddle today. A Bontrager (trek).
It's more comfy than the San Marco I had, but I still feel like I should be further back on the saddle. I'm slipping forward a bit.
Is that a function of saddle height, front/back or tilt, or perhaps all 3?

 

[cyclintom]

If you're slipping forward, you're either tilted forward or your saddle is too far back. Or your stem is too long.

 

[metropical75]

I slid the seat forward a bit. It's not tilted. Same stem I've been riding for a decade, not that that necessarily means anything.
Perhaps another bit forward.