I know exactly my size and preference for fit on my current bikes which are both modern design compact frames. I know where to put my saddle in relation to the BB and the best distance from saddle to bar as well as saddle to bar drop. I'm in the process of building up an 80s frame with horizontal too tube, and threaded forks / headset and am trying myself in knots about fit. The top tube on the classic frame is almost 20mm longer (horizontally) than my modern frames. Couple this with the fact that my modern bars are also compact, I'm panicking that the reach on the classic frame (with classic regular drop bars) is going to be waaaay stretched out for me. From my fag packet calculations it looks like even if I find an 80mm quill stem, I'm still going to have 10-15mm more reach than on my compact frames. So my question is, are non compact frames expected to give a more stretched position or is there some factor of saddle height in relation to top tube that I am not factoring in? I am currently riding a 52cm frame, I have about 150mm of seatpost showing. I've purchased a 54cm classic frame.