This will be an interesting post. Did the fitter say if you needed a larger or smaller bike? a closer reach or a further reach? How old are you? Are you flexible? or not so much? Do you want carbon fiber or titanium?
Usually if there is neck pain your seat height in relation to your handlebar height is too high, which means you either need a larger bike and/or a bike with a shorter top tube to shorten the reach. To see if that is the situation you could install a riser (spacer), and/or flip the stem if you have one of those with a different angled end, this will raise the bar, but to bring the bar closer you'll need a shorter stem. Raising the bar will in effect bring the bar a bit closer but it may not be enough, only trial and error will figure that out.
You might also only need to do some proper exercises and stretching.
"Most cyclists tend to have a sustained contraction in their upper back/neck region while riding. This means inadequate circulation (and oxygen and nutrients) to the upper back and neck region. A sustained contraction means your muscles are under continuous load and not moving (not alternating between a contracted and relaxed state which is desirable).
So what types of things can be done to help? You probably already know that stretching is advantageous to avoiding muscle related injuries. In addition to stretching the neck and upper back muscles, you can also benefit from these two exercises: elbow presses and reverse shoulder shrugs.
Elbow presses are a great blood pumping exercise that helps an ample blood supply reach the upper back and neck region. This will counter the sustained sub-maximal contraction that cinches down on the muscle’s small arteries which occur with long bike rides.
To perform elbow presses, bring your elbows out away from the body at the shoulder level. Then pull your elbows back as far as you can, causing the muscles around your shoulder blades and upper back to contract before you bring the elbows back to the starting point. Continue performing reps until you get a mild burning sensation in the muscles of the upper back and neck.
Reverse shoulder shrugs are also great because they make the muscles in the neck and upper back region alternate between full contraction and full relaxation.
Reverse shoulder shrugs are performed by shrugging your shoulders upward toward your ears and then back down toward the ground and behind you. It is important to do reverse shoulder shrugs (shrugging up and back) rather than regular forward shoulder shrugs. Forward shoulder shrugs have a forward rotation which makes the back hunch forward into a chimp-like posture.
This prevents the muscles of the upper back from contracting enough to accomplish the desired “contract, relax, contract, relax” movement pattern. Doing this exercise properly will get the muscles in the upper back and neck pumping periodically and cyclists will notice a positive difference within a few times of performing the exercise.
There are also some basic neck movements that may help neck range of motion and circulation in the neck. Here are the ones that I recommend:
1. Flexion (chin to chest)
2. Extension (head up)
3. Right and left rotation (chin pointing toward the point of the shoulder)
4. Right and left lateral flexion (ear to the shoulder).
Cyclists can also fall prey to another common problem that occurs in the upper back and neck area known as Thoracic Outlet Syndrome or TOS for short. T.O.S. is a condition in which blood vessels or nerves are compressed, usually by overlying muscles, as they pass from the neck region into the arm. This can cause pain, numbness, and weakness in the arms and hands. Typically, athletes in strength sports like football and baseball are most susceptible, but cyclists may also experience thoracic outlet syndrome-type symptoms.
The difference is that cyclists are more likely to suffer because of muscle tightness or spasm at the base of the neck. Again, muscle movement and stretching are effective in relieving TOS related discomfort."
That above information came from a former distance runner, Ron Fritzke, D.C. currently races his bike in California. He’s been helping patients with their back problems for the last 22 years in Mount Shasta, California. In addition to serving on the sports medicine team at the College of the Siskiyous.
I would try the cheaper alternatives first before rushing out and getting new bike, with any changes and especially exercising and stretching programs, it takes time to see results, but they will slowly occur and could save you big bucks. If you after 3 months and you're still in misery with no signs of improvement than look into getting a new bike, but this time test ride the bike for a long time to make sure it will work for you. You may want to look at various endurance bikes too, these have a taller headtube for increased comfort in you upper back and neck.
Some taller headtube endurance bikes are the Eddy Merckx Mourenx 69; Trek Domane S 5 endurance bike; Specialized Roubaix series; and there are other bikes as well of course.