I am about to purchase my first road bike, and have am veru confused over what size I should look at. I am 6 ft tall and have been directed to several different sizes. The bike i am interested in purchasing is on sale, but is 54 cm, the owner feels this is big enough, is this only a sales pitch? What sizes of bike fit heights of people? Thanks very much... By the way, the bike is an Orbea, any suggestions?