The reality for many of the fast local venues is seaweed. It is essential to have a fin that sheds weed, yet still lets you unleash the potential of the flat water and wind available.
We introduce a new concept in weed fin design. The Tribal line looks unconventional due to the large curvature on the blade leading edge.
With straight leading edge weed fins, the rake has to be set for the span-wise flow to pull seaweed along the leading edge to the tip. This causes the lifting surface in the tip to be located a long way behind the centre of rotation of the board (trim axis). This is not really a problem deep off the wind with short speed fins, but as you go larger the problem becomes worse. In the end the straight leading edge is a big compromise in balance. Upwind or across the wind, where the centre of pressure of the fin is too far back for optimal balance with the rig, is where you notice this the most.
The Tribal line solves this problem with a more upright base region, which helps to keep the centre of pressure forward, giving more of the same feeling on the water as an upright fin. Weed is accelerated down the leading edge as the curvature increases, leading to a much better matched set-up than conventional weed fins.
We also used some techniques to control mechanically induced twist, so that the fin doesn’t lose power as you load it hard and try to bend it.
Off the wind these fins are incredible. The larger sizes offer unlimited top speed in larger boards, and in testing we had our crew smash their medium slalom board PBs by as much as 6kts…
These fins are perfect in slalom boards when seaweed is a problem, or when you want to turn your slalom board into a speed board.