Different saddle means different bike fit??

[!TREK4ME!]

Hey Guys,
I've got two identical road bikes, set-up the same way, with all the same components and everything, except the saddles are different. One is on my go fast bike and it is 160mm wide and the other is 145mm wide. The 145mm saddle bike I use more for touring and have a front bar bag and rear bag with rack. Both of the saddles are the same length, just that one is a little narrower than the other.
My question is:
The measurement on both bikes from the back of the quill to the front end of the seat is the same, but the one with the narrower saddle seems stretched a little more than the other. Why is this??
Also, should there be any differences in bike set-up between a touring bike and a go fast bike??
Thanks,
PJ

[nfmisso]

For me it is all about comfort.

Measurement comparison should be from the center line of the handle bars to the center of the saddle.

[RBurrelli]

You are likely positioning yourself further back on the narrower saddle. That would be a normal reaction.

[!TREK4ME!]

Awesome !!...
Thanks !!!...,
PJ