When a Father and Son Develop a Raceboard

With the Katana and the Tsurugi, Starboard is introducing two new race boards designed for a different style of paddling. Behind the development are multiple SUP world champion Shuri “Shrimpy” Araki and his father and coach, Takuji Araki. Their idea: It’s not raw power, but rhythm, a high stroke rate, and maximum efficiency that make the difference.

A Family Story from Okinawa

At just 20 years old, Shuri Araki is already one of the world’s most successful SUP racers. The multiple ISA and ICF world champion from Okinawa is known for his exceptionally fast paddling style. Behind his success is his father, Takuji Araki, who has been coaching him for years and has played a decisive role in shaping his paddling style.

Now, father and son have drawn on their experience to develop their own line of race boards. The Katana is Shuri’s personal signature board, while the slightly wider Tsurugi makes the same concept accessible to a broader group of racers.

The concept behind these two boards is remarkable: While many traditional race boards are designed for long, powerful paddle strokes, the Arakis are designed for shorter, high-frequency strokes. The board is designed to convert these movements into propulsion as efficiently as possible.

The secret lies in the rear

At the heart of the new design is the patented Narrow Box Tail™. The narrow, box-shaped tail features sharp 90-degree edges that serve a specific function with every paddle stroke.

The rhythmic motion causes the stern to dip slightly into the water and then rise back out again. Takuji Araki compares this effect to the pumping motion used in foiling.

When the board enters the water, the sharp edges grip the water and act like two additional small fins. This is designed to help the board stay on course even in crosswinds and choppy water. When the board is lifted out of the water, the edges break free from the water again, reducing drag.

According to Starboard, this design even allows for the use of a smaller fin, which can further reduce drag.

The sharply contoured bow also follows this design concept. Inspired by a Japanese katana sword, it is designed to cut cleanly through choppy water while maintaining speed and control.

Two separate footpads with a small gap between them help the rider find the right foot position without looking. An additional pad at the rear provides support during tight turns around buoys.

Katana and Tsurugi—two boards, one philosophy

The Katana is clearly designed for ambitious competitive paddlers who already have a refined technique and a high stroke rate.

The Katana 14′ x 20.5″ has a volume of 290 liters and is designed for elite racers weighing up to 75 kg. With a weight of just 9.5 kg, as specified by Starboard, it is one of the lightest race boards available.

The Tsurugi incorporates the key design features but offers more width and a slightly wider stern. This is intended to make it easier to control and to accommodate paddlers who are not at Shuri Araki’s technical level.

Model	Volume	Recommended Rider Weight
Katana 14′ x 20.5″	290 L	Up to 75 kg, Elite
Tsurugi 14′ x 21″	285 L	Up to 75 kg, experienced racers
Tsurugi 14′ x 23″	300 L	Up to 85 kg, Advanced
Tsurugi 14′ x 25″	325 L	Up to 95 kg

All models are built using the Carbon Reflex Sandwich D2 construction, which Starboard describes as its lightest full-carbon race construction to date. A Flash Plus carbon fin is included.

A New Approach to SUP Racing?

With the Katana and Tsurugi, Starboard is taking an interesting approach. Instead of focusing exclusively on shapes that are as narrow as possible and maximum glide speed, the company is placing greater emphasis on the interplay between board design and paddling technique.

What’s particularly exciting is that this development arose directly from the collaboration between a world-class athlete and his father and coach. The two didn’t simply adapt an existing board to Shuri’s needs; instead, they developed a concept specifically designed to support his unique paddling style.

Independent tests will have to show whether the advantages of the Narrow Box Tail™ hold true for other racers and under different conditions. It also remains to be seen how well the design works for paddlers who tend to use long, powerful strokes.

One thing is certain, however: With the Katana and Tsurugi, Starboard is bringing fresh ideas to race board development. And the story of Shuri Araki and his father makes this new release particularly interesting.

According to Starboard, the new models are now available for pre-order. You can sign up here.