You may have hit it on the nose. When I went to the LSB about it last year thinking it was a frame-size issue, they put me on the trainer, took pics, and said that it was just a posture issue, that I needed to roll my pelvis forward. I tried to do that for the later half of last summer but it was unnatural, or at least my muscles didn't want to go there.

While I could look at something with a more upright posture, I really cant afford to sell/buy right now...