An ERJ170 Captain reported an aileron control resistance during the first four degrees of yoke movement after which aileron control was normal. Maintenance found no control cable anomalies.

Narrative

After takeoff from Runway 17L; we started a left turn to the east in our climb to 5000 feet. As I started the turn I noticed resistance in the ailerons during the initial movement of the controls from top of center. The aircraft turned normally but I was having difficulty avoiding over controlling the aircraft; especially at shallow bank angles. I found myself using more than normal force with two hands to make the initial turn; however; once I was established in the turn the aircraft performed normally. I also found if I released the controls in a shallow turn the aircraft would jerk back to wings level. This was abnormal behavior; usually the aircraft will remain in the bank or smoothly roll back to wings level . During the climb there was no turbulence; so we didn't have any interference from the environment. I stated the abnormality to the First Officer and once we were established above 10000; I transferred the controls to the First Officer in order to take some turns. The First Office also noted the control stiffness to the left and right through only the first 4 degrees. After the initial turn things seemed normal until we relaxed the controls in a shallow bank. The First Officer noted the aircraft jerked back to wings level as well. During this time I called Company; and we spoke regarding the control stiffness. We made the joint decision (MOC; Dispatch; and flight crew) to continue to our planned destination. The autopilot was able to fly the aircraft entire route. During approach in strong surface winds I again noticed the stiffness in the controls. We were able to land uneventfully. We did a control check on the ground and did not notice the same interference as we noticed in flight. After we arrived at the gate we worked with local maintenance to diagnose the problem. The mechanics eventually disconnected the ailerons. I do not know the outcome of the problem.