I'm in the market for an endurance bike. I am 6'1, 34.25 inch inseam, arm length 27.25 inches and trunk 24.75. According to Bike Fit Calculator at competitivecyclist.com I need a top tube length of 54.5 to 55 cm. This seems very short. Currently I ride a 21 inch Fuji Absolute 3.0, with an effective top tube of 60 cm. I've ridden two 100K rides on this bike with very little discomfort. I rented a 58cm Trek Domane and rode it for 55 miles with only a bit of shoulder stiffness/discomfort which was surprising since I wasn't used to the new riding position coming from the flat bar Absolute. It had a 56.7 effective top tube (compared to 60 on the Absolute) but I felt a bit stretched which doesn't make sense. What's really confounding to me is that I rode a friends 61 cm Fuji Roubais and only felt slightly stretched with a effective top tube of 59.
I'm looking at 2 used Giant Defy's right now, one is M/L and the other is L. Their top tubes are 56 and 57.5. My first choice for an endurance bike is the Synapse but really just trying to find the best used bike deal on 5 different endurance bikes....Secteur, Sportif, Synapse, Defy and Domane.