Originally Posted by
Fly2High
With all this discussion, I have some questions:
1. The OP is short torso, long legged. Some say to get a smaller frame and a long seat post. Wouldn't this put the rider in a very aggressive position where they would look like a guy on a high bar stool reaching for a napkin that fell at the base of the stool?
2. When you raise the seat, doesn't reach also get affected since the seatpost is never vertical and slightly laid back?
3. Doesn't every rider strive for a similar angles on the bike (forward lean, arm to back, elbow, knee, etc.)?
4. What if the OP is looking for a more upright, endurance posture? If you are fitting the OP on an endurance frame and will result in a racier posture, what if the OP doesn't want that? how will they get an endurance posture? Is it not possible? Same for the reverse, if they end up with an endurance posture but really wanted a race posture.
5. With the OP's long legs, how do you prevent the knees from hitting their chest if they are on such a high seat post and they are leaning well forward?
6. I do not understand how the OP would be able top get a handlebar to seat heigh with zero difference in height (endurance setup) with the suggestions offered? Please explain.
thanks for the clarification. I am close to being in this boat too.
Endurance bikes generally have taller head tubes, so the issues you ask about re: drop to the bars would be alleviated that way. On a smaller, aggressive frame you would use steerer spacers and a flipped up stem to svoid the problem. On a larger, aggrssive frame you would use a shorter stem to deal with the long top tube.
Reach is not affected by raising the seat. The distance fron the seat to the bottom bracket needs to be a constant for a given rider. Thet is a first principle. You don't dick with that. Then reach is measured horizontally from the bottom bracket to head tube. That doesn't change with seat tube height either. So no, rider reach to the bars is not affected improperly by seat height. When the seat is at the right height, the saddle setback will be right assuming constant seat tube angle. Supposing you go from one frame to a different one with a different seat tube angle? Each degree is worth 1 cm of setback. Over the range of common seat tube angles in adjacent sizes there can be a +/- 1 cm difference in saddle setback more likely 0.5 cm. Most saddle rails can easily accomodate that. What goes on in front of that is what we are talking about.