Before changing lanes, a motorcyclist should ensure that their speed is moderate. This is crucial because maintaining a manageable speed allows for better control of the motorcycle during the lane change. A moderate speed enables the rider to react appropriately to any changes in traffic, obstacles, or conditions in surrounding lanes. Additionally, it assists in maintaining stability, as high speeds can lead to difficulties in handling the motorcycle, especially in narrow or unexpected situations.
While the other options involve important aspects of motorcycle safety and maintenance, they are not as immediately impactful on the process of changing lanes. Adjusting the helmet ensures safety, sufficient fuel prevents running out of gas, and functional brakes are essential for overall vehicle safety. However, these considerations do not directly influence the immediate execution of a lane change as effectively as controlling speed does. Thus, moderate speed is a vital focus for enhancing the safety and effectiveness of maneuvering in traffic.