Quote Originally Posted by SadieKate
Pain in that spot for me means a lack of conditioning. More riding and some upper body strengthening exercises.
Everyone made great suggestions, but I agree most with SadieKate and maillotpois (core strengthening). When I stop riding for 2 months it takes me about 400 km to get my back and shoulders used to the bike again. I feel the pain in the shoulders but actually I think it's because of the back's lack of strength. Before I'd throw the fit out of wack, I'd try to ride it just a bit more, unless the pain is acute, in which case fit is definitely the issue.

I had a bike that was the right height but way too long when riding in France recently (I rented a bike and had no choice with regards to size). My shoulders hurt so badly when I had to stay on the hoods for a long time (descending a 40 km hill!!) that I had to stop to stretch. So length could be an issue. But especially if you've been off your road bike for a while, I'd consider