changing out seat post on a rad expand 5

[radex5owner]

So I have the opposite problem that most rider have, I'm short (5'1") and I want to know first the diameter of the seat post to see if I can get a lay-back post where the seat is positioned back. ,  I can still reach the ground when stopped but  have a better pedal stroke for riding.  Because I have the rad basket on, I only have about an inch to work with but feel it will give me the distance for better knee expansion.

[JimInPT]

My MiniST2's seatpost diameter is 27.2mm, which I believe is the same for all Rad bikes including yours. 

I replaced the factory unit with a Redshift suspension post, which I love and has a pretty good fore/aft range on the rails.  It's 350mm long and fits these frames very well.

[handlebar]

So I have the opposite problem that most rider have, I'm short (5'1") and I want to know first the diameter of the seat post to see if I can get a lay-back post where the seat is positioned back. ,  I can still reach the ground when stopped but  have a better pedal stroke for riding.  Because I have the rad basket on, I only have about an inch to work with but feel it will give me the distance for better knee expansion.

Seated to pedal, I can touch the ground with one toe, but when I stop I can sit with the balls of both feet on the ground. The saddles of both my bikes tilt forward so I can easily slide forward and downward as I stop. As I ride, pressure against the bars and pedals keeps me from sliding forward. It's the old-school way to get stability when stopped and full leg extension when underway.

As a rule of thumb, when a rider sits in pedaling position with his foot on the pedal that's in front and level with the crank, the front of his knee should be over the spindle. (It can be checked with a plumb bob or, more elegantly, the plumb line of a laser level.) You may find that a layback post would not help you.

[John Rose]

So I have the opposite problem that most rider have, I'm short (5'1") and I want to know first the diameter of the seat post to see if I can get a lay-back post where the seat is positioned back. ,  I can still reach the ground when stopped but  have a better pedal stroke for riding.  Because I have the rad basket on, I only have about an inch to work with but feel it will give me the distance for better knee expansion.

Would you still be okay for the reach to the handlebars?