Dan-at-Duotone wrote: ↑
Thu May 09, 2019 5:26 pm
Sorry for the delay in response, been out of the office and just noticed this (you're always welcome to PM me, thanks Toby for the heads up)...
1. Yes, we found that the injection molded fuselage was not up to the stresses of SUP/windsurf foiling and would break more easily than we liked if you hit bottom/floating debris even when kiting. So for 2019 we've designed a burlier mast and fuselage for use with our SUP/WS foils compared to the ones for our kite foils... Any mast and fuselage strong enough for SUP/WS use noticeably slows/detracts from performance on a kite foil and any kite-specced mast/fuselage does not hold up to the added stresses of WS/SUP use. It also resulted in us switching to an aluminum fuselage and pairing up with some people who had been involved in America's Cup foil design in order to analyze our whole kite foil platform. One of the biggest issues with our 2018 North foils (and many other foils on the market) was flex and vibration... No matter how perfectly a foil is designed, once it starts vibrating it creates extra drag without any lift and performance suffers significantly. So one of the primary priorities in creating our new foil lineup was increasing resilience and reducing flex/vibration.
2. We also placed a priority on making the foils backward compatible, trying several iterations using the same fuselage and mast. We were working with designers and fabricators who had been involved in America's Cup foil design with our whole foil project and ran a bunch of computational fluid dynamic analyses. After looking at it from every angle, though we wanted to keep the same fuselage and mast, it became clear that the 2018 North foil platform could not give the structural integrity we needed. There's no point in designing better wings if the mast/fuselage are the factors limiting performance.
A. In order to reduce vibration a longer chord was required for the mast. We also added a pocket to the fuselage where it connects to the mast to stiffen this connection, all of this results in significantly lower vibration and less flex, however it also means the 2018 North fuselage is not compatible with the 2019 Duotone mast, nor vice-versa.
B. To maximize strength and reduce twisting and vibration, the screw hole spacing for the wings (front and back) was increased, so the old wings will not fit on the new fuselage
C. The mast to board connections are the same, if that's any consolation, so a Speedster combo will work on any 2019 Duotone foil board, and the 2019 Spirit range of foils will work on any older-model North foil board.
D. We also switched from the carbon compound construction we'd used in the fuselage/wing of the NKB foil... The only place we're still using that composite construction is on the wings of our pricepoint Spirit Freeride foil. The fuselage for all Spirit foils is Aluminum, as is the mast. The wings for the Spirit Carve, Spirit Surf, and Spirit GT are all full carbon.
I know this is not the answer you wanted. We have always worked hard to make our gear as backward compatible as possible... We kept the same bar platform for most of the 19 years we've been in business, so you could fly any North or Duotone kite on any 5th element bar, mixing and matching years from at least as far back as 2006 through 2019. In this situation I know we made several attempts to continue to use the same platform but it was either reissue a product we weren't happy with just to keep it backwards-compatible or make a big jump forward and lose compatibility.
Just to be clear though, the Spirit Surf, Spirit Carve, and Spirit GT all use the same mast/fuselage/rear wing, so switching between these requires only switching out the front wing.
TL/DR: 2019 Duotone wings will not fit on 2018 North fuselage, 2019 Duotone fuselage will not fit on 2018 North Masts.
Hope this helps and feel free to respond with any questions, here or by PM.