frogman

I have my road bike dialed in pretty well, comfortable riding, just got back from a 60 mile outing and no issues. I am concerned about the fore and aft saddle position however. It is supposed to be good to set up the saddle position so a plumb bob from the knee cap intersects the pedal center. On my bike the plumb line is 1 1/2" forward of the pedal center. Should I be concerned ?
How critical is this ?

DrIsotope

frogman

I have a longer torso and relativley short legs, I am comfortable with my more forward position it seems. I tried the balance method for finding the neutral position of fore and aft setback they describe where you sit up after pedaling for a while up keeping your arms forward and let loose of the bars to see if my hips shift position fore or aft. I pass the test, I stay in the same place. So even though the plumb line from my knee is forward of the pedal a little I seem to be balanced. I think I will keep things where they are and not worry be happy

Iride01 

As far as using a plumb bob -- I would not make that the end-all-be-all decision for where your saddle should go. Perhaps it might be thought of as a starting point to set your saddle the first time and then adjust from there as your body tells you what feels right after actual rides. IMO.

Cyclist0100

My first question is "How did your saddle get set up in the first place?" In other words, is the saddle in it's current position because you determined through trial and error that's the position where it's most comfortable?

With regard to your question about the "knee over ball of foot" test, which uses the plumb bob to which you refer, it's out-dated, old-school thinking and is no longer considered critical. And to be clear, it's not where your knee is in relation to the pedal, it's where your knee is in relation to the ball of your foot on the pedal with the crank at 3 o'clock.

Carbonfiberboy 

In the first place, "from the kneecap" is incorrect. One drops the plumb bob from the bony protrusion just below the kneecap. That makes a difference as you will see. It's known as knee over pedal spindle or KOPS.

This KOPS thing is not particularly outdated. It's still used as a starting place by many fitters. Having got that right, one then looks at balance, meaning fore and aft saddle position, realizing that changing saddle position will also affect saddle height.

What's critical is not KOPS, it's balance. For most folks, KOPS and proper balance are about the same, which is the reason that shortcut gets used so much. KOPS really has nothing to do with pedaling mechanics. Fore and aft position does affect which muscles get used more and less, but that's trainable and doesn't seem to make much difference.

Cyclist0100

Carbonfiberboy said it much better than I did. Balance and properly positioning your center of mass between the wheels are the critical factors upon which good bike fitters will focus. Done properly your knee position will generally pass the KOPS test, but this is a secondary outcome.