1. How you surf. Powerful or strong surfers tend to use bigger stiffer fins providing more drive, speed and hold through turns. The same fin for a less powerful surfer will make the board too stiff therefore harder to turn. However, if you use a fin that is too small or flexible, you will lose drive and speed. Without speed it’s more difficult to turn.
2. Board design. The relationship between your board and your fins is an important one. You can make a bad board go good with the right fin and you can make a good board go bad with the wrong fin. Some basic points to consider. Boards with lots of concave: may require a fin with greater area, more depth or sweep (rake). Boards with vee or no concave: perform better with a more average size or smaller fin. Boards with wider tails (fish): go better with bigger fins. Boards with narrow tails (guns): go better with smaller fins. Board with channels: go better with smaller fins that have less tip area.
3. Surf conditions. Point breaks, reef breaks and beachies all offer different surfing conditions. While one fin may be perfect for your local point break, it may not be the right choice for a short punchy beach break. Fins that are more swept back result in longer drawn out turns which are generally suited to long point break type waves. Fins with less sweep (upright fins) and a wide base are pivotal and enable shorter tighter turns that are good for fast hollow beach break type conditions.
For expert advice and testing go to an official FCS TEST DRIVE CENTRE store. The best way to learn about fins is to try them yourself! surffcs.com