What size single fin do I need? The size of fin you choose depends on the type of board you are riding, your style of surfing, and your weight/size.
Generally speaking, high-performance boards with 2+1 setups use a middle fin between 7.5 and 9 inches in length, with shorter fins being easier for smaller surfers to turn, while longer fins lend themselves to more powerful turns and stability while on the nose.
Traditional single-fin logs typically use fins between 9 and 11 inches long, with longer fins providing more stability while noseriding but sacrificing maneuverability, particularly for smaller surfers or those without a lot of power.
Where should I place my fin in a single fin box? Fin placement depends on the type of waves you are surfing and the feel you want from your board. Generally speaking, the farther forward a fin is, the “looser” (more maneuverable) it is, but the less stability it provides in critical sections, such as in the barrel or when noseriding.
Sliding the fin back adds more control but makes the board more difficult to turn, which can especially be an issue on longboards, which are already somewhat large and unwieldy. Noseriders typically have the fin as far back as it can go, while boards that are intended to be surfed aggressively and with a modern flair might see the fin moved forward in the box (toward the nose) to loosen it up.
That being said, different people like different feels, so it’sa good idea to experiment and move the fin around a bit between sessions to see what works best for you.
How will the fin(s) size affect performance? Generally speaking, longer fins provide more hold and control, while shorter fins are easier to turn. Meanwhile, wider fins provide more drive but tend to be more difficult to maneuver. That being said, there are a number of other factors that affect how a fin performs, including outline, rake, foil, and flex.
What does flex do in a fin? Flex is often built into the final 1/3 of a fin’s tip, and provides a lively, springy feel through turns. This is due to the fins ability to flex during the turn, then snap back into position as the turn is completed, projecting the board into the next section. That being said, flexible fins are not ideal for noseriding, as they sacrifice stability when on the nose.
What does rake do in a fin? Rake is the amount that a fin sweeps back and is measured by how far the tip of the fin is behind the trailing edge of the fin’s base. Rake makes a fin turn better, while an upright fin will provide more stability, but at the expense of maneuverability.
Does my weight play a role in deciding which fin(s) I should buy? Definitely! Lighter surfers will have trouble turning longer/smaller fins, while larger and more powerful surfers may find that they overpower shorter/smaller fins. The best way to figure out what size fin you want is to experiment with a bunch of different options.
That being said, smaller surfers (below 150 pounds) often use fins between 8 to 9 inches for high-performance boards and 9- to 9.5-inch fins for noseriders, while larger surfers will tend to use 9- to 9.5-inch fins for high-performance boards and 10-inch+ fins for noseriders.
Should I make my fin(s) selection based on the type of waves I'm surfing? Yes! Different fins work for different types of waves and different styles of surfing. For example, long, wide, upright fins such as pivot fins and D fins provide a lot of stability but don’t maneuver well, which makes them good for noseriding in small waves. Meanwhile, more aggressive fins such as rake and flex fins are more maneuverable and work well in larger, hollower waves that call for high-performance surfing.
Do your single fins fit in a certain type of fin box? Virtually all single fins fit in the standard, universal single fin boxes you’ll find on practically every longboard and mid-length.
Why is it important to invest in fins? We pay a lot attention to the boards we ride, but often forget to take into account how important fins are for riding waves. Shaper Dan Mann once said that surfboards are simply the platforms we stand on while surfing our fins.
Because they have such a pronounced effect on how we surf, you want to make sure you are using quality fins built from quality materials. Most high-end longboard fins are made from fiberglass, which provides durability and rigid stability.
