Radiator Fins
Increasing the radiator fin count, or number of fins per inch, provides more surface area for the transfer of heat to the cooling air. However, increasing the fin count increases the restriction of the radiator to cooling airflow. Lower cooling airflows result in lower heat transfer. In every installation there is an optimum combination of fin performance and core restriction that will produce maximum heat transfer. Increasing the core restriction from this optimum point by increasing fin count will reduce the heat transfer performance of the radiator. The Motocross Bike is a tough enviroment for radiators, as ideally louvred fins should be best, however they are easily blocked.