Editable motion curve won't respond

[pizzaplanet1940]

I'm working on a run cycle and need to round out the edges of my leg's motion curve, but the curve doesn't change its shape when I do anything to the splines in the graph editor. (The dead giveaway for this is that nothing happens to the motion curve when I move frame 0's Translate Y value upward.) I've already factory reset Maya and it didn't help. What should I do?

[hamsterHamster]

The description sounds confusing to me, as it is not clear what do you mean with "motion curve" - a motionPath or an animationCurve, Also, you could have posted at least a screenshot or three of your scene and current state of the graphEditor with issues.