SUP Lessons: Stand Up Paddleboard Fin Placement
This is the most common set up, especially among beginners who are most worried about keeping their board straight. The single fin setup allows the paddler to go in a straight line (which is also beneficial for racers) and reduces any side-to-side action that multiple fins may encourage.
Fins are secured in a fin box on the bottom of the board with a nut and a screw. Loosening this allows you to either move the fin forward towards the nose of the board or back toward the tail end of the SUP. If you move it forward, it makes the board easier to turn in the water. Move it back, and it stabilizes the board which helps it draw a straight, easy line.
2-Fin or 3-Fin Setup
Adding lateral fins, or what are colloquially referred to as “side-bites” increases the maneuverability of a stand up paddleboard so that it’s easier to do quick turns or tricks on the water, similar to a surf board. This setup usually means that the center fin is a little smaller than a single fin installation with two even smaller fins flanking it on either side. You can remove the center fin for a 2-fin setup which is also good for surfing and tracking on flat water.
The “side bites” improve a board’s performance and control--placement of them can be tricky. Start with the side bites tips aligned with the back of the center fin. Push the center fin in ¼” increments either forward or backward until you find the sweet spot.
More often than not, SUP racers will go with a single fin setup for flat-water racing. Remember: fin placement toward the back of the board will help you keep the straightest line. Single fin setups don’t promote drag in the water and will help you go straight for long distances.
SUP racing fins also come in varying degrees of flexibility and each has their advantages and disadvantages. Flexibility is helpful if you get into a situation where you might hit obstacles--a rigid fin might send you flying off your board. A fin with some flex to it would give you a little give so you’re more likely to stay on your feet. The benefit of stiff fins, however, is they’re good for longer race boards and keeps you stable through rolling swells, wind, and waves. Flexible fins don’t perform as well downwind.