Originally Posted by dgasmd
Funny. I would have said a 55cm frame as he has shorter legs and what seems like a longer torso/arms. I am 5' 7" with the same insem as him and I am getting a 53cm frame with a 120 mm stem and 38" handlebars
If he has short legs then a 55 would have zero standover clearance and put him in a near Superman aero position. He would have about 3 inches of seat post showing and likely no drop at all.
I'm 5'8 with short legs and this is my 53cm Pedal Force with a 13cm stem.