The best Harley seat for long rides is one that offers both comfort and support. A good quality, well-padded seat will provide the rider with a comfortable ride while still providing enough back support to prevent fatigue during longer trips. When selecting a seat for your Harley, consider features such as adjustable lumbar support or an air cushion system to adjust the firmness of the cushion. Also look into seats that offer additional back padding, allowing you to customize your comfort level even further. Be sure to check out reviews from other riders who have tried different types of seating before making your decision - it's always better to be safe than sorry!