Originally Posted by
pakossa
Is this another one of those "starting point" rules, or is it more definitive? I checked my fit, and found somewhat of an overlap (assuming I'm doing it correctly, and that you're referring to the vertical plane -- see photo). I arrived at this reach by going as long as I can with the reach while still being able to pedal at "full power." (If I increase the reach just a cm, or 2, my power drops at least 20%. I assume this is due to my ridiculously short torso-to-leg ratio.) Or, could that mean my saddle position isn't quite right?
Attachment 545437
Note that your upper arms do not make a 90° angle with your torso. They should. I would increase reach until they did. I don't believe you about the 20% power drop with increased reach. I doubt it would make the slightest difference. The only difference really is in long distance comfort. Without that 90° angle, you're always using muscles in your arms and torso which don't need to be used. Over many hours that begins to tell on you.
Re saddle position: Only you can tell if you feel balanced on the bike. I don't think it's possible to see that from a photo.
In general, you want it to look like this in terms of pedaling, fit, and balance: