Behind the design with Ralf Ralf Grösel 


Today we catch up with designer Ralf Grösel to go behind the design of the EVO D/LAB

Hi Ralf, The Evo D/LAB is new to the Duotone lineup for this year, what can people expect from this new model?
Well, the Evo D/LAB comes from our experience with the Juice D/LAB. The Juice D/LAB is also a three-strut construction, it comes in 14,15 and 17 square meters and with the EVO D/LAB, we have been able to extend that range down to six square meters, which ensures that you're able to have the most performance, the most all-round kite in the industry from a six-meter all the way through to the Juice D/LAB in a 17 square meter, which is a massive range.

For those who are maybe not familiar with the Evo D/LAB, can you explain where it sits in the Duotone range and what kind of riding styles are suited to the Evo D/LAB? 
The Evo D/LAB is the top of the range high performance kite. After 18 years with Boards and More, this is the benchmark in all-round kites and the design of the Evo in general. We have the Evo and the Evo SLS, which is the more sporty version of the Evo and now the Evo D/LAB. The D/LAB is not more sporty than the SLS, it is differently positioned in terms of the feeling and sensation that you're having. .

The Evo D/LAB is extremely light and due to the Aluula material, it has certain flight characteristics, which are very unique, and very unique within the industry in general. The kite sits further out in the wind window, it is very slippery through the air, you can use the kite in the lightest breeze, but also in extremely strong wind conditions. So the range of use for the kite is unmatched. It's unmatched within the range of Evos, but it's also unmatched when compared with every kite on the market. So, it’s something which is really setting a benchmark. As a designer, it’s a product I could not have imagined a couple of years ago because Aluula was not available, now we have something exceptional and something you simply have to experience

For kiters that haven't tried a D/LAB kite yet, can you explain what kind of differences and benefits there are?
Yes, it's actually quite simple to understand. Let's imagine you want to ride on a hydrofoil because it's really light wind conditions. You have eight knots on the lake and you have your hydrofoil, you can take a nine square meter Evo D/LAB, and with the nine you can ride in eight knots of wind with a hydrofoil and a 950 wing. This is only possible because of the way the kite flies and the way the kite goes in its turn and creates power, it's unique. It captures a lot of energy and the Aluula material acts like a soft spring. You can load up that spring and energy which is loaded into the kite, during the turn, then softly releases the energy when the kite turns around and climbs up. This is something very special and very unique, because of its lightweight and specific material properties. So on one side, you have the ability to ride in eight knots on a hydrofoil on a nine square meter kite, but then you can take the same kite in 30 plus knots of wind on a twin-tip and boost the highest jumps possible. I think this is what explains it the best, the range is unmatched. We have team riders like Andrea Principi, who is currently riding the Evo D/LAB eight meter, and he claims that he's able to jump more than 10% higher with this than any other kite, just imagine 10% more height if you are already jumping 30 meters. It is something which you have to experience and it’s not that difficult to achieve, you don’t need a lot of skill, everything comes very naturally. It is very intuitive, very easy, very predictable, very smooth. Another great thing is the dampening effect of the kite, the way it deals with gusts and rough conditions is unmatched. Sometimes it might feel a little bit less sporty in comparison to the Evo SLS, for example. But in the end, if you put the things together in the right way, then you're able to load the kite up extremely precisely to jump extremely high, so that gives you a real advantage in the gusts and challenging conditions. 

So it's high performance, but smoother than the SLS. Is that right?
Yes, you have Evo on the left side of the spectrum, and then you have the Evo SLS in the centre and the Evo D/LAB, let's say on the right. The Evo uses the classic materials and has wonderful damping characteristics in rough conditions for someone with not so much experience. For someone who doesn’t have the chance to hit the water every weekend, it’s a fantastic product because it makes everything easy. This is the kite that does a lot of good things for your riding, even if you don't have a high skill level. The Evo SLS is definitely more demanding when it comes to abstracting the performance out of it. If you have the right skill level, it will 100% do the trick for you, you will be able to jump higher, you will be able to experience the race car feeling, it is very sporty and super precise, it talks to you in a very direct way. The Evo D/LAB on the other side is not a more extreme version of a sports car, it’s like a car which has more horsepower, but with softer damping, it’s something which makes it extremely easy and fluid to deal with and due to the lightweight construction and the three strut design, you have the perfect balance between the performance attributes and the possibility to fly the kite in extremely light wind conditions, but also, to boost yourself, when it’s 30 plus knots with a nine-meter. It has all of the features from the Evo and the Evo SLS combined but put together in the best way, it is not more extreme, it is just extreme in the wind range and range of use, but not in the skill level which is required to use the kite.

I think that's something we are seeing even the pro team looking towards, as big air contest judging criteria rewards technicality difficulty more, it's not just about a single powerful loop but more about adding technicality and combinations.The new generation seems to enjoy a kite that can give them the lift and height they need but is somewhat of a more consistent, predictable loop, maybe not as extreme as a Dice but it enables them to push a lot further with the technical tricks.
Yes, this is spot on, this is a very good explanation because that's what is required for extreme kiteboarding, which actually requires these aspects from a kite, with the Evo D/LAB you can jump high, which is very important. You have to have a certain height to pull the manoeuvres needed to win a contest, like during the King of the Air. But then it comes to the question, how connected are you with the kite? Are you able to make double loops? 

These days double loops are all about the way the kite goes into a turn and then hooks you up. The kite has to be extremely precise, so the rider can control it and knows the position of the kite within the wind window. This is very important because they are likely upside down with the board off. You really have to feel what the kite is doing, so this connection must be there. This is one point and then the hook, the way the kite catches you has always been a very important issue and a very important flight attribute, and the Evo D/LAB is doing all of these things absolutely great. The team riders are saying that they find themselves in the position to pull these tricks, because they trust the kite to follow their steering input and they're confident it's going to catch them. This puts their mind at rest and there is no doubt in the back of their mind when they're doing these radical tricks.

Were there many challenges during the development of this kite or was it fairly straightforward after the extensive development you’ve already done with the Juice D/LAB?
It was pretty straightforward with the prototyping because the Evo D/LAB is not based on the Evo SLS, it is based on the Juice D/LAB. The Penta TX material of the Evo SLS is really different to the other raw material, it has very different characteristics, so it doesn't make any sense to start from the Evo SLS and try to implement the Aluula material.

I have been able to abstract the knowledge I've captured from the development phases with the Juice D/LAB and put those into the Evo D/LAB. So, in the end, you have a Juice D/LAB in 17 square metres, and then you have an Evo D/LAB in six. So the delta is 10 square meters. Of course, you have to completely fine-tune every size and adjust these kites to the new material combinations. We wondered in the beginning if the smaller sizes were necessary, but we quickly figured out the huge benefits of the smaller kites with the way the kite deals with the gusts, the softness and the way it communicates with you and makes your riding experience better. So it absolutely made sense to have the smaller sizes.

With Aluula performing in such a different way to Penta TX and Dacron, what other alterations were needed to get the flight characteristics you were looking for?
With new material, every parameter changes. For example, the leading edge diameter is totally different, because the material is so much more slippery in the air. The positioning in the wind window, which is a key element of the drivability of a kite, is different. You have to adjust that and then also adjust the profile geometry to the new leading edge diameters. You have to adjust the bridles to the overall radius and twisting and turning behaviour of the material. What is very interesting is that we decided not to use any Flex Struts on the Evo D/LAB, because the kite is already responsive enough. Flex Struts are fantastic to make the kite more agile, to make it more responsive when it comes to reducing the delay in turning when you initialise the turn. So the Flex Strut is a very good option to control that movement, but that was not necessary with the Evo D/LAB. The struts and tips are there to stiffen everything to make the kite more rigid, it fits in and suits the overall flight performance, but, optically, if you just forget the graphics and the panel design, the Evo, Evo SLS and the Evo D/LAB look very similar, but in the end, they are three completely different models when it comes to the important design figures, you have a different material, which means you have to create an entire set of different parameters to make that material work, to abstract the best out of the specific material. This is extremely important and something I think we will see in the future in general, that based on the material, we will have certain flight characteristics implemented into the kites and if you change the material or models with different materials you will have different flight characteristics and properties.

So the tuning options remain the same across the Evo range, with the three options to adjust turning speed and bar pressure, what are your recommendations for air pressures?
That's a very good point. The air pressure of a kite hugely changes the flight characteristics, for example, I weigh 83 kilos, and maybe I'm a little bit heavier than the average rider but for me, the kites work with seven and a half psi. This is the way we develop and test. So, pump the kite to seven and then one more stroke on the pump to ensure when you release the hose that you really have the seven psi in your kite. But for much heavier riders, say 110 kilograms, they of course use the same size, let's say a nine meter in stronger wind conditions, this means the structural stiffness is heavily dependent on the internal pressure of the kite. So these people tend to pump the kite harder. The same applies to our team riders, they're pumping the kites as hard as the pump can actually pump them, 10 psi for example, which with the D/LAB construction shouldn't be a problem at all. But you always have to keep in mind that when you pump it hard like that, for a normal customer it would be an extremely rigid kite and the turning abilities will decrease, it will be less comfortable to ride. The delay in the turn will be greater which is not a good thing. So I personally would recommend using something between seven and eight PSI for everyone for all the models, but never less than seven, please never pump your kite lower than seven because then everything goes too smooth and it's going to be very imprecise.

You develop the kites with specific line lengths and bar sizes, what are your recommendations for bar sizes and line lengths for the different sizes of Evo D/LABs? 
Yes, I’m very particular about bar sizes, from 17 to 11 square meters I develop these kites with the wide Click Bar on 24 meters lines, which is the standard setting if you have the wide bar, and from the 10-meter down I use the small Click Bar with 22-meter lines. There is a reason for doing this.

The 24-meter lines on the bigger kites ensure that the kite sits a little bit deeper in the wind window, which creates a little bit more grunt and gives you the feeling of more power. You don't need this on a smaller kite, what you want to have on a smaller kite is the ability to de-power when you sheet out the bar. So it is very important that the kite can sit further in the window and this is achieved by using the 22-meter lines. The extra two meters make a huge difference, so I personally recommend if possible and if you have the budget, to please get yourself both sizes of the Click Bar. I personally like the Click Bar more than the Trust Bar, because I love the simplicity of it and the click itself. I think it has awesome functionality.

Thank you very much Ralf, some really interesting insights!