Thanks for all the responses. I figured it had to be mostly form. I plan on picking up a trainer this weekend for the winter months and will definitely use it to do some spinning intervals and practice my cadence.

My saddle is right on as far as I know, I don't rock and according to all measurements I've done its correct. I dont have any issues with the saddle height otherwise, so I figured it was something I just needed to work on and get a better pedal stroke technique.