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The guys at Duotone caught up with designer Ralf Grösel about the two and a half year development process that advanced the Juice D/LAB to the absolute top end of what’s possible in the industry right now. Packed with future technology, Ralf explains the challenges that had to be overcome in the production process with the new material Aluula and how Duotone succeeded in creating unreal new kiting possibilities in hardly any wind at all — get a taste of the sensational feeling of kiting in 4-5 knots! The Juice D/LAB sets a totally new benchmark in light wind performance and it’s pretty obvious why Ralf considers this gamechanger as “the most interesting kite I’ve created in my entire career.”

Welcome Ralf, great to talk to you today, could you tell us where this kite sits in the Duotone range and what people can expect from the new Juice D/LAB?

It’s a pleasure for me to talk about the Juice D/LAB, a kite I’ve been working on for two and half years now. Juice D/LAB stands for Duotone Laboratory. This is a division of Duotone where we are creating kites which are the absolute top end of what is possible in the industry right now and the Juice D/LAB is sort of a revolution and definitely the most interesting kite I’ve done in my career, it’s amazing!

Tell us about the materials that have made the Juice D/LAB possible.

The Juice D/LAB features the Aluula material, which is currently the lightest material available on the market, it’s 80 gsm, for example, Penta TX on our SLS series is 130 gsm so it’s quite a big difference. With the Juice being the industry standard in its class, the Juice D/LAB is the cherry on the cake when it comes to ultimate light wind performance. I have changed quite a few variables to make it work, on the technical design and then also on the production side. That is one of the reasons it took us so long to get this kite ready as we had to change various production and sowing techniques to make the product come to fruition in a way we were satisfied with.

We’ve seen Aluula come out in other brands kites, but there definitely have also been some issues with the material, how difficult was it to overcome these difficulties?

It was the biggest, it’s not material as we are used to dealing with, it’s closer to a laminate construction and these laminates are extremely vulnerable to point loads such as needle holes. So to make it work we have done various tests of different seam constructions at the Lab we have in Germany. We had to establish a new sowing line at our factory in Sri Lanka to make it happen. It took many prototypes to validate it. This was more related to the structural stability and long term durability than adjustments to the flight characteristics. The original Juice was already a very good base for me to progress so the challenge was definitely to make the material work the way we would like to see it work.

Could you tell us how the material properties differ from Aluula to Penta TX to Dacron?

If you take the Juice it comes with a 140gsm Dacron on the leading edge. Aluula is not a normal woven material, it’s a laminate with two foils and some woven yarn in-between, it has a completely different character in every single regard. When you take a kite design from the computer model and simply change the material, it doesn’t work as it will deform in a totally different way, for example when you inflate the kite the material will elongate in different areas, so you’re receiving a different kite. It’s still the same construction, but you’re receiving a different kite. For example, the overall weight is different, the way the tips are controlled.

When the leading edge is different, that automatically affects the trailing edge so you end up designing a new kite, but you know exactly what you are looking for. It’s not as if you are starting from zero, you have to find a way to consider the previous design to make something that comes close to what you know to give you the right starting point and then from there work your way to the ultimate goal, which is always the handling characteristics. On a light-wind kite, this is the key aspect, that when you send the kite down (in the wind window) that the up stoke delivers as much power as possible, as this keeps your momentum on the water. If you have lightweight material, you don’t need so much energy for the upstroke performance which allows more room for tuning to the handling which is where we focused.

The Juice has set the benchmark in light wind performance kites up until this point, how does the Juice D/LAB compare?

It’s a game-changer for the industry I would say. Four knots of wind is nothing, you can barely see ripples on the water and these kites can start to fly in conditions this light! It’s quite amazing! With a foil board and a 13-meter Juice D/LAB, an average guy like myself, 80kgs can start to go in 5 knots of wind and even as low as 4 knots if there is no current in the water and this is just revolutionary! The feeling you have to be able to be on the water, because of that upward stroke power and lightness, because of the energy I can put into a loop and the kite hooks me up, that sensation is insane. We had just approximately three days of no wind here in Egypt and out of 200 kiters there were only two kiters out and that was Marian (Hund) and myself. Of course, this is the limit, if the wind drops from four to three knots then it’s over to start the kite, if you are already riding then it’s not a problem as you have the apparent wind to keep you going. It’s really a revolution.

Yeah, that does sound amazing! Every day is a kite-able! What about relaunching the kite, is it possible to get it out of the water when the wind is that light?

The four knots is a magical number, if you have this wind with no current in the water you can reverse water launch the kite as you would a soft kite. You have to train this technique and in winds this light it’s not a safety concern as it might be trying this technique in stronger winds. If there is more wind, for example, six or seven knots then you can relaunch traditionally, but if you are really trying to ride in conditions that push the limits then you have to learn the reverse launch technique by pulling on the back lines.

The Juice D/LAB is available in both 13 and 15 square meter sizes, could you tell us for what riding styles, boards and weights they have been designed for?

With the Juice D/LAB, we have done something we haven’t done before in our range. We have the 13 meter and 15 meter, both kites are very different. The 13 meter is developed to be the ultimate foiling kite, so even in terms of racing and the 15 meter is a dedicated grungier kite that has the purpose to keep you going on a twin-tip in the lightest wind possible. I think it’s important to give you some numbers; I’m 82 kilos in my wetsuit and harness, if I use the Ultraspike 165 in combination with a 24-meter click bar and 15 Juice D/LAB, I can go in 6-7 knots of wind, let’s say 7 to be on the safe side. This kite has been developed to get a 100kg person going on the Ultraspike in just 8 knots of wind! This is something that I think is really awesome and revolutionary! For example on Mallorca/Spain, in the bay of Palma, they have a daily sea-breeze of 8 knots of wind in the summer times, so that means in a light wind summer sea-breeze you can kite with a twin tip, and I think that’s pretty incredible!

Let’s talk a bit about the feedback and feel at the bar, will it be a familiar feeling to the previous Juice?

Absolutely, one of the biggest goals was to have something that feels identical, because this is what it is all about. The kite is extreme but it should not feel like an extreme. This is what is incredible, if you have 4 knots and loop the 13 meter it starts to pull you, you start to wonder where is that pull and power coming from? It’s coming because the kite has great turning abilities, but I have to mention that kiting in these conditions as light as 4 knots is really extreme, if you’re kiting in 4 knots then it drops to 3 there is a limit and 3 knots is that limit. You still need some wind but the wind range is pushed to the extreme minimum. The 15 meter with my 82 kilos, I start to reduce the power on the click bar even at 6 knots as I feel the kite is really pulling me, it’s extreme how much pull it can create! You have to get used to how much power the kite can create, you don’t feel the wind, or see the wind, yet the power it can create is something you have to experience, I think for everyone who tried it there was a learning curve.

You’re currently in Egypt, how was the reaction from the kiteboarders when they are all sat on the beach unable to get going and it’s just you and Marian on the water?

Clearly, if you are the only guy out on the water people are very interested in what equipment we have. They were amazed by what was going on with D/LAB. There have been rumours for quite some time and now we have the officially approved kite here and out there showcasing what is going on. The wind here in Egypt is probably one of the worst you can experience when conditions are light. With its thermal winds even the wind pattern is 200 meters into the water and you have crazy wind shifts to 90 degrees in just a couple of seconds.

I would describe it closer to paragliding where you are searching for thermals to keep the kite in the air than kiting, you have to check and scan the water and look for areas where there are more ripples to search the light gusts. When we are foiling on the 13 meter and there is a gust of 7 knots it’s easy to go 20 knots with the apparent wind, with upwind angles so great you don’t know which direction the wind is coming from! That is a very cool experience! When you hit that low end and are riding over crystal clear water, you can just look into the water and see the fish 5 meters deep, because there are no other reflections or disturbances on the water, it’s bizarre!

Are there any plans to take this kite to the Olympics?

It’s a good question, I think that this kite of material development is leading us to something new, I think kitesurfing will change with products like this as it makes kiting even more accessible. I don’t know what point it will lead to, but I feel it will change the industry in a wider sense as there are not many wind-powered vehicles that can go this fast in only 4 knots of wind. There are the America Cup boats but that’s in a different league. Having this kite available as a commercial product with user-friendly intuitive handling, easy to understand and fly. I really do hope the public will enjoy it and am excited to see where it will lead.

What are the recommended air pressures and setting options available?

It’s our standard-setting of soft, medium and hard steering. I recommend leaving it on the medium setting as this was how the kite was designed and offers the best compromise. For inflation, 7 psi minimum, you can always go 7-8 psi. It’s not that the material is weaker it’s just as mentioned before we have been able to solve the issues we had with our first prototypes with this material. When looking for maximum performance, structural stability counts.

With Penta TX being a slightly heavier but stiffer material, do you see a future where we’ll see the two combined?

We’re already testing this, we like to use Penta TX in areas where we need the perfect load distribution, for example, the tip area. We have an entirely new set of materials after approximately 20 years with just the same materials, so who knows where this is going to lead us with different combinations, I believe this is just the beginning of this new era.

Great, thanks for your time again today Ralf, if you could give us a summary of the kite and who it’s suited to.

The Juice D/LAB is the ultimate light wind kite currently available on the market, if you are looking for an option that delivers riding in the lightest winds possible then you should try to get your hands on one and see what it delivers. I believe it’s a massive game-changer, even more than the introduction of Penta TX on the SLS range and that was a big change for the industry. I think the combination of this kite, the lightness and characteristics will lead to something new. I hope you have the chance to ride in 4-5 knots of wind and feel that experience, it’s quite amazing!

This article first appeared on the Duotone website here.