PRICE IS FOR 1 FIN
The X-Twin-R was developed together with our Teamrider Robby Swift.
The fin is very similar to the X-Twin in the top characteristics with agility, release, early planing, excellent upwind and speed performance.
With more area and a thinner foil the fin can be more forgiving and helped with advancements in wave sailing. The improvements have also helped in big wave ridig conditions at Ho’okipa, Maui and Chile.
Best suited: Medion-big waves, on- and side-shore
Lengths: 14.5-18.5 cm (by 1-cm-steps)
|Fin Area (cm2)||101||110,5||120||129||
MUF Fins selector
* This graph is based on a body weight of 80 kg. Each 10 kg more/less the next bigger/smaller fin has to be selected.
Maui Ultra Fins design
Sailboard performance and sailing characteristics are more influenced by the fin than originally thought. Simply speaking, the fin must hold a great part of the sail forces to create a stable and straight ride. Those fin forces must be provided under all sailing conditions and no spin-out should occur.
MUFins airfoil design is based on highly sophisticated engineering methods as they are applied in aircraft wing design. But compared to aircraft wings, fins operate at a much more lower Reynolds number. That‘s why airfoils developed for aircraft wings like the NACA series - although widely used - are not really adequate for fin applications.
In the last 25 years, especially in Germany, modern airfoils have been developed specifically for low Reynolds numbers. MUFins uses this valuable knowledge with some modifications for the new fin development.
The airfoils are optimized with computer programs that can calculate all aerodynamic parameters of importance.
This new approach in designing MUFins sets new standards in fin performance.
MUFfins delivers unmatched stability and speed range, unbelievably upwind performance, they are extremely spin-out resistant, great in jibing and agile on the waves. Nothing else compares.
One ride and you will never look at windsurfing the same again.
FAQ about Maui Ultra Fins:
1. What makes Maui Ultra Fins so exceptional?
Maui Ultra Fins uses specifically developed foils which have been optimized for the windsurfing speed range and conditions.
MUFins provide nearly twice as much lift at low speeds compared to conventional fins with the same fin area.
MUFins also allow a nearly twice as high angle of attack (flow angle) than conventional fins.
On top of this, the fins provide outstanding upwind performance and spin-out resistance and even the drag is much lower compared to conventional fins which makes MUFins so fast.
All these characteristics allow a very stable ride and jibing in all wind and wave conditions.
2. Why do our fins have no flex?
When sailing, the wind can be very gusty (sudden change in wind speed and direction), which leads to sudden changes in sail forces that are very uncomfortable.
To compensate the varying forces sail tip flex was invented that lead to very easy sail handling.
However, there are no gusts in the water which have to be compensated. Due to the fact that the airfoils of conventional fins have limited spin-out margins, flex was introduced to reduce the spin-out problem. But as a result performance is lost.
Because MUFins are so spin-out resistant, flex is not needed and full performance is available in all conditions.
Fin evaluations have shown that no flex is preferred.
3. Why do our wave fins not have the typical wave fin outline?
To start with: The typical wave fin outline is regarded as highly inefficient under hydro-dynamical aspects due to the extremely high rake (swept back) at the tip.
To provide flex in wave fins, airfoils ended up being very thin at the tip which results in early spin-out.
Our impression is that the wave fin outline was heavily influenced by simply copying from sea animals, when fins first were used on surfboards. Since then the outline has never changed and few people have questioned this approach.
Many tests of MUFins in wave conditions have shown that they work perfectly in small waves as well as in really big surf with their elliptic and relative straight shape.
4. Why do our fins have an elliptic outline?
The so called induced drag of a fin is produced by pressure equalization at the tip of the fin. This drag is minimal, when the fin outline is elliptic. This has been well known for over 80 years.
That‘s why MUFins have an elliptic outline - to reduce the induced drag.
5. What is G-10 material?
G-10 is a glass epoxy laminate which has been used as electro-static dissipative material. It is very stiff and it offers excellent machinability and tight tolerances.
All Maui Ultra Fins are made of high-quality G-10.