The North Duke has a large remit within the North range. Not only was it designed to be a power wave sail for heavyweight riders such as ex-team rider Bjorn Dunkerbeck but also a flat water freestyle sail for World Champion Gollito Estredo. It sits above the Ice and Ego for power within the North wave range.
"Basically, the requirements for a Power Wave and a Freestyle sail are very similar: great planning potential combined with maximum handling and good controllability. Up to a size of 5.4m², the DUKE was therefore designed as a powerful Wave sail according to Björn’s specifications. Since it possesses the greatest trimming versatility of all our Wave sails, it can also be easily controlled by medium-weight pilots" – North website
off water description
The Duke sports the longest boom and luff length of the sails in this group. It sets on the recommended SDM mast with a fairly flat batten profile but a decent amount of fullness set forward in the sail.
There is good tuning versatility allowing the sail to be set with less downhaul and more outhaul for a gruntier feel or more downhaul and less outhaul for a lighter feel. As with all North Sails this year, there is great attention to detail. The North visual trim system (VTS) is the best in the business and works a treat. The recommended harness line position (printed on the sail) also works well. Other notable details include a decent downhauling pulley block, a boom height scale, PVC badge (to keep the luff open when threading the mast) and elastic tie strap to keep the sail tightly rolled.
on water description
The Duke has a unique feel within this group as it pulls from a long way forward and feels soft and light in the hands. The sail has quite a lot of spring to it and, as such, power delivery is amongst the softest.
Set with minimal downhaul and outhaul there is certainly a lot of power in this sail and it feels really nice with a great balance between useful power and light feeling. As the wind increases however it becomes noticeably tight in the leech and requires more downhaul to get it to release.
This is when the sail starts to feel a little less comfortable. With more downhaul (max recommended setting) the bottom of the sail pulls from well forward and feels fairly solid but the head, despite being loose, doesn't release quite enough to ease the backhand pressure. You therefore have quite a forward pulling sail most of the time but in the gusts have to contend with some backhand pressure.
This backhand pressure, combined with the long boom length, does make the sail feel a little ‘draggy’ at the top end and less manoeuvrable. Having said this, most of our test Clones were around 70-83kg, but one of the heavier Clones really enjoyed the North when well powered up, so perhaps the Duke just needs a bit more body weight to release properly at the top end...
Unless overpowered, the Duke performs well in manoeuvres with a nice neutral feel to it and a soft rotation.
To summarise, if you want a Freestyle sail that has good power, with great handling, the Duke fits the bill nicely. If you weigh less than 85kg and are looking for a wave sail, you may be better looking at the Ego or Ice.
The Duke was developed as a wave sail for heavy weight riders such as Bjorn Dunkerbeck and a freestyle sail for lighter riders such as Golito Estreda and this becomes pretty apparent when you try the sail. The Duke feels powerful, light and manoeuvrable in lighter winds but seems to require extra body weight (85-90kg+) to get the best out of it in stronger winds and waves.