The previous reply has some generally good information. I don't think the original post gave us enough information to really deal with your problem. However I would like to point out this, not to contradict the previous post, but just for contrast. I find that thinking about the "motions' or "movements" is the most harmful thing I can do for my own piano playing. I tend to think in much more general terms, just whether something feels good or not. Usually it is a musical key that will solve the solution.
I am aware that such an idea is hackneyed and sounds cliched. However it is really proven success for me. If a passage is feeling uncomfortable (externally can sound in lots of different ways, including choppiness, for example the LH arpeggios in second page of Liszt sonata gave me lots of choppiness at first) I do things like exaggerate the inner melodic shapes. It is death to try and play long runs as if it was just one straight line. At the end, it may sound like that, but you are actualyl shaping all of the notes inside in different ways.
According to Konrad Wolff, a student of Schnabel, Schnabel use to imagine long scales divided in irregular ways, for instance 5 notes here, 3 there, 4, etc. (from Wolff's book, "The Teaching of Artur Schnabel"). All of these inner groups, inner phrases, have their own shape which correspond to create the effect of the whole shape. This may sound terribly vague. Perhaps if you are interested I can give you some concrete examples. But my point is, when you start to shape these small groups melodically, at least when I do it, I find that the physical problems take care of themselves. And I have found results in this in hugely varied repertoire, for instance Mozart concertos or Rachmaninoff Preludes.
Maybe somebody can elaborate more than I am able. Though if you have any questions do ask.
Walter Ramsey
P.S. I am reminded something that Bernhard wrote a while ago, that even-sounding piano playing requires uneven movement. So when you are working on my vaguely worded "melodic shapes" think also how timing plays a role in any melody, and how you can subtly take time in phrases that won't even be noticed by outside listeners. In other words, perfect evenness is an illusion.