SONIC – Developing the fastest SUP race fin

The aim was to increase top end speed for elite paddlers while enhancing the maneuverability and surfing characteristics of somewhat cumbersome race boards. The Sonic is aimed at Advanced to Elite Pro Racers.
By Chris Freeman 3 years ago

The SONIC was developed to be the fastest, most maneuverable SUP race fin on the market. That goal was achieved through the culmination of 12 months of design testing by SUP racers on Maui and around the world. This fin has gone on to win numerous races & has helped our athletes claim multiple world titles, making this this go to fin for many elite and advanced padders. 

Building on the success of the TIGER and MALIKO standup paddleboard racing fins, we wanted to make something drastically different that adds a new dimension to SUP race board tuning. From the Sonic’s early conception, our aim was to make a race-winning SUP fin that gives our athletes the advantage in the heat of battle. The Sonic was created to increase top-end speed for elite paddlers while enhancing the maneuverability and surfing characteristics of otherwise cumbersome race boards. While Intermediate paddlers will find the Sonic adaptable, it is a fin built specifically to enhance the performance of Advanced to Elite Pro Racers.

How did we develop the SONIC SUP race fin?

In many ways the Sonic was a dream project. Our other SUP race fin model—the Tiger—proved so successful that there was no real rush to bring out a new product, and that enabled us to be free-thinking and try a wide range of concepts and foil variants. Detailed foil analysis and 3D modeling are the fundamentals; this is what our designer Tom Hammerton spends his days toiling over so paddlers can find maximum enjoyment and performance on the water. Where modeling produces the baseline information, real-world testing on the water ensures that the mathematics are correct both in theory and in the ocean with multiple variables apparent. Our initial prototype fins are all made in black G10 material, precision milled in our factory to enable us to rapidly test multiple options while keeping development costs under control.

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Testing: How we made The SONIC the world’s fastest SUP race fin

We began with our extensive testing on flat water on Maui with Fiona Wylde & Bernd Roediger, we are lucky to have the Kahului harbor, flat, no wind and ideal for GPS testing. At the same time Leo Nika and Sonni Hönscheid were testing the prototypes in Europe in a wider range of conditions. The testing process took considerable time with the collection of quantitative and qualitative data, comparing and contrasting our models with a bunch of fins from leading brands and input from a range of paddlers. We are luckily to have access to a range of boards and special thanks must go to SIC Maui, Naish, Starboard & Kanaha Kai Maui, who always make sure we have the latest race gear to test on. When testing you need to be careful to interpret but not over analyze data, especially when there are external forces (e.g. elemental factors like wind, chop or human factors like effort and fatigue). While GPS data is important, often it is the qualitative data—feel, responsiveness and rider versus rider comparisons— which help guide ultimate design decisions. Our project management software enables riders to give instant feedback to Tom as he looks for trends in the rider chatter. What might seem like a throwaway comment to a rider can be the golden piece of insight that Tom is listening for.

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How big should my SUP race fin be?

As we went smaller with our prototypes we were going faster, but what is too small? As you reduce SUP fin size the potential speed increases and the course time thus decreases. However the variance in speeds/times also increases with less stability and tracking ability created by less surface area, and at a point going smaller becomes a riskier strategy for racers. As we reduced the fin size in our prototypes, some riders started to get slower course times even if there average and peak speeds were higher. They were having to paddle longer because tracking was lost. Eventually we reached a size so small that all riders were finishing slower. There was an observed increase in speed as we reduced size, then we reached a point where any further decreases in surface area resulted in deteriorated performance. That’s the balancing point we sought to perfect with the Sonic.

While some smaller paddlers (e.g. Fiona Wylde) were able to go smaller most paddlers experienced their peak speeds and quickest times using the 18cm with the v4.1 foil. Fin size is just one aspect of design, but our proprietary foil is truly the biggest factor in making a fin fast and remains constant no matter the fin size. At any size, the foil is the most influential factor in determining speed. During our testing for pure speed we also tested how performance changed as the water state became rougher. While it is more difficult to achieve accurate GPS data in these conditions, qualitative feedback from the riders is very informative (it is truly amazing how elite paddlers can feel small changes). It’s more challenging to paddle in rougher water and hence a smaller fin is harder to ride in these conditions. The 18cm version we settled upon gave us enough stability in the rougher conditions while the 17cm prototypes were too small for most testers in confused waters.

Responsiveness: The SONIC fin must turn quickly

The new fin had to improve the maneuverability of 12’6” and 14′ race boards. On flatter water we aimed to increase the responsiveness with foot steering rather than railing the board to change direction (needed with bigger fins). We wanted paddlers to stay as flat and fast as possible, so the Sonic SUP race fin was tuned to enable riders to steer their boards without the need for aggressive rail work. Testing showed that these changes enabled riders to fine tune their path for hitting buoy turns and reduced recorded GPS distance. Another observation was that the increased steering ability aided riders while drafting—they found it easier to stay in the wake and also to overtake competitors.

The most fun aspect of testing was the surfing component. Race boards are always tricky in surf, but the Sonic minimizes the clunkiness by loosening up the turning ability and enabling improved carving and flow. The goal of a quality SUP race fin acting in surf is to be able to link flowing turns so you can maintain your speed and also conserve energy. After extensive testing, we accomplished that to perfection with the Sonic.

The advanced maneuverability of the Sonic translates into enhanced downwind performance, and the combined speed and flow of the fin enables paddlers to catch, surf and connect the downwind bumps more than ever before. As the fastest downwind paddlers aim to paddle less and surf more, this is what we were looking to further enhance.

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How is the SONIC carbon SUP race fin produced?

Our Pro Carbon SUP race fins are produced using Resign Transfer Molding (RTM). RTM is primarily used to mold components with large surface areas, complex shapes and smooth finishes, hence it is ideal for making premium quality fins. This production process delivers the best possible strength to weight ratio. We use steel molds as they produce higher quality results than other, cheaper materials. Our quality control (QC) process is the most rigorous in the SUP fin industry and any fin that doesn’t meet or exceed our quality benchmarks is destroyed. Once the factory QC is complete all Pro Carbon fins come to Hawaii for final inspection by Chris and Tom. Only fins that have been signed off as perfect ever get to enjoy the water.

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What do the paddlers say about the Sonic SUP race fin?

“I use the SONIC for downwind & surf races. It loosens up the board to maneuver between bumps & planes really well, it gets great speed but still changes direction quickly. Downwind, especially without a rudder, the most important thing other than speed is the ability to change direction fast without sacrificing too much stability. The Sonic does that best in my opinion.” 

Connor Baxter, Multiple Racing World Champion

“The SONIC opens up a whole new range of tuning opportunities. It is FAST, extremely maneuverable in downwind & surf and has the quickest acceleration off the line.”

Fiona Wylde, 2016 Racing World Champion

“The SONIC is the superior all water fin for anyone racing in Hawaii and California (or anywhere in open ocean).”

Bernd Roediger, Downwind racing specialist

“The SONIC race fin quickly became my favorite, I have had my best downwinders, fastest sprints & most enjoyable (race board) surf sessions while using this fin, I love how it livened up my Starboard All Star on the flat & on the bumps.”

Chris Freeman, Black Project Hawaii

How does the SONIC compare to the MALIKO & TIGER?

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Who is going to benefit most from the SONIC SUP race fin?

By design this is not a fin for everyone! We hope that after reading the above comments the Sonic’s suitability for your paddling style will be clear. Experienced paddlers are those most likely to benefit from the Sonic’s performance characteristics. Paddlers who like a free and fast feeling, and are confident on their SUP race boards, will experience obvious benefits. If you like grinding out long distances with a low cadence, then the Tiger or Maliko will be more suitable for you. If you have a higher cadence and want to enhance your agility, then the Sonic race fin is for you, and if you like to surf your SUP race board, the Sonic is certainly the fin of choice. If you are an experienced downwinder, the Sonic will help you improve further. The Sonic has a 45° initial angle on the leading edge and becomes progressively more raked, so it’s great at shedding weeds and trash. Given it’s shallow depth of just 18cm, paddlers working with shallow waters will also like this fin option. If you are planning to attend a race like The Pacific Paddle Games or The Gorge Paddle Challenge, you’ll no doubt want a Sonic in your fin quiver.

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SONIC SUP Race Fin – Overview

  • Depth 18cm / 7 in
  • Area 214cm² / 33 in²
  • 45° leading edge with progressive rake
  • RTM Pro Carbon construction
  • 150 grams / 5.3 oz

More Paddle Related Articles & Content

Learn more about: The Sonic

Picking the Right SUP Race Fin: Advice from Champion Racer Connor Baxter

Maui downwind champion Bernd Roediger takes surfing to the river. 

Words: Mike Misselwitz / Black Project
Photos: Black Project


  SUP, Fins, Choosing a SUP race fin, Sonic, Racing
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