Hybrids and top tube length
From what I've seen, there is no good documentation online about proper fitting of a flat bar road bike. Most especially, since most hybrids are compact frames and most sizing methods don't take this into account. After looking at a lot of charts and bike geometry diagrams I have come to the conclusion that the proper sizing method for a hybrid (flat bar road bikes) should be based on effective top tube length and it should be around 2-4 cm longer than that on a flat bars. Can someone confirm this and elaborate on this subject?
I put the pointy part of my elbow against the nose of the saddle and outstretched fingers come to about three inches from the bars, I'm good. I can work with that. For drop bars, outstretched fingers reaching handlebar is OK.
There's no 'rule' here, it seems to me; it all depends on the ride position (reach) you want. What is true is that a bike sized properly for drop bars will have too short a t/t for most, simply due to the forward throw of the drop bars, which adds anywhere from 6 to 8 or so cms. to the total reach (i.e. when riding on the hoods). So, if you ride say a trad. road bike with a 54 cm t/t, you would probably want at least 56.5, or even up to 59 (as with, say, a trad. xc mountain bike) with flats. Giant, for example, does this with their drop and flat-bar road bikes: a Medium Defy has a 54.5 t/t, a Medium FCR (or the new Rapid) 56.5.