stehsegler,
What is the logic behind a longer extension?
I struggle to keep the leach tight AND get the bottom batten of pop through. My thought is if the sail moves up the mast it is on a softer section so the leach wiill open sooner with less dowhaul. For that reason I have been using less extension than the specs. I will have to try it longer.
Thanks Mate!
A good instruction video on pumping onto foil
Interesting - Simon and Ben both pump up quicker and more efficiently than me (at 1.40).
They both start pumping with their foot in the strap - my foot is in front of the strap (otherwise I seem to sink the tail).
Going to have to try harder to keep pressure on the mast foot and my foot in the strap because it definitely looks like better technique.
When I pump the foil on my narrow tailed Bolt 135 the tail initially sinks so I move my feet forward, front foot is in front of the foot strap, and then start pumping the foil, then as I build speed and the board starts to plane I move back into the front foot strap and apply tail pressure to lift off. Depending on the wind speed, I can move back into the front foot strap before the board starts to plane and quickly apply tail pressure to lift off.
There seems to be two different phases to pumping.
The slower, initial phase seems to benefit most from sail pumping, throwing the sail forward, and staying pointed downwind. Can start without the front in the footstrap just to get basic board speed.
The second, faster phase seems to benefit most from more lateral sail pumping or even close to a static sail (if it's a large sail), with lots of hip movement to foil pump. Front foot in strap and pushing forward during certain parts of the pump.
I'm not the best pumper but I'm getting better and can get up in 8 knots on race gear, probably a little later on my slingshot setup and a smaller sail. It feels different in many ways. On the smaller sails I can't put a lot of hips into the foil pumping like I can with a big 9.0, at least without taking a bath in light winds.


With my kit, I do not need to pump the sail in light winds (8-9 knots), just pump the AFS W95 foil with F1080 cm2 wing on a Goya Bolt 135 L 80 cm wide board and an Aerotech 8.0 Freespeed sail, rider weight 86 kg.
Foil pumping is much more efficient on a 80 cm wide slalom style board, than sail pumping which takes a lot of energy and balance while trying to lift off. I do use the sail as support as I pump the foil by making sure the wind is pressing on the sail, but do not pump the sail.
Now maybe those of you on wide foil boards do need to pump the foil and sail, due to the increased drag of the wide board when on the water. Someone here mention for every additional 10 cm in board width you need an additional 1 meter of sail to get up.
@Awalkspoiled - interesting idea about trying to tune the sail via a different batten. I'd previously (back when I used to sail regularly) considered trying to add another batten to the sail, around/below the boom, to try to stabilize the baggier lower section of the sail, but ultimately figured I'd probably do more harm than good. (My Infinity sails have a batten in that area, whereas the Idra does not.). I've got a few tube battens for my larger 8.1 sail that I no longer use, so perhaps I'll take a look and see if I can find something a little stiffer in that collection.
@Sandman1221 - also interesting - I'd been under the impression that the wider foil-specific board shapes were specifically intended to get the board up faster, but it sounds like that may be a double-edge sword?
@Awalkspoiled - interesting idea about trying to tune the sail via a different batten. I'd previously (back when I used to sail regularly) considered trying to add another batten to the sail, around/below the boom, to try to stabilize the baggier lower section of the sail, but ultimately figured I'd probably do more harm than good. (My Infinity sails have a batten in that area, whereas the Idra does not.). I've got a few tube battens for my larger 8.1 sail that I no longer use, so perhaps I'll take a look and see if I can find something a little stiffer in that collection.
@Sandman1221 - also interesting - I'd been under the impression that the wider foil-specific board shapes were specifically intended to get the board up faster, but it sounds like that may be a double-edge sword?
jims, yup, for light winds the wide boards are going to drag a lot more, that's one reason why I am still sticking with the Bolt 135, then in high winds and waves the slalom boards are like a surf board and much easier to control if you catch a rail deliberately (to reduce speed) or by accident, or decide to surf downwind (i.e., board on the water, but moving fast!).
stehsegler,
What is the logic behind a longer extension?
I struggle to keep the leach tight AND get the bottom batten of pop through. My thought is if the sail moves up the mast it is on a softer section so the leach wiill open sooner with less dowhaul. For that reason I have been using less extension than the specs. I will have to try it longer.
Thanks Mate!
The idea is to bring the centre of attack high up away from the board which assist with lift. RE batten not rotating, is your mast the manufacturers recommended bend curve?
So, got out with my dual-camber 6.0 yesterday (still a 90's era sail, but late-90's, and a very solid design), and found that I can pump 'foil-style' with the 6.0 pretty comfortably. (I'm still not super efficient at it, but I can do that movement much more naturally with the 6.0 than with my smaller sails, which feel more natural pumping/rotating in the other direction).
I was a little hesitant to put the 6.0 on the Wizard 125, simply because it's been a long time since I've done any sub-planing windsurfing, and I found the Wizard to be a fair bit tippier than I thought it would be, so was worried I'd be all over the place w/ the larger/heavier 6.0. Truth be told, things felt a lot more stable with the 6.0 than with the 5.0 or 4.3, in low-wind putt-putting-around conditions - just provided a bit more pull to hold onto and balance with. (Sadly, the wind was very low and variable, so I only got one short flight on the 6.0, which lasted just the duration of a little puff. When slogging around, however, I was able to point much higher into the breeze with the 6.0, though.)
Anyway, I think there is definitely something to the type of sail, relating to the ease with which it'll pump in which direction (ie, rotating the mast tip CW or CCW in the pumping cycle), at least for me and my limited skills!
I think I'll be taking the 6.0 out on the local puddle more frequently from now on.
So, got out with my dual-camber 6.0 yesterday (still a 90's era sail, but late-90's, and a very solid design), and found that I can pump 'foil-style' with the 6.0 pretty comfortably. (I'm still not super efficient at it, but I can do that movement much more naturally with the 6.0 than with my smaller sails, which feel more natural pumping/rotating in the other direction).
I was a little hesitant to put the 6.0 on the Wizard 125, simply because it's been a long time since I've done any sub-planing windsurfing, and I found the Wizard to be a fair bit tippier than I thought it would be, so was worried I'd be all over the place w/ the larger/heavier 6.0. Truth be told, things felt a lot more stable with the 6.0 than with the 5.0 or 4.3, in low-wind putt-putting-around conditions - just provided a bit more pull to hold onto and balance with. (Sadly, the wind was very low and variable, so I only got one short flight on the 6.0, which lasted just the duration of a little puff. When slogging around, however, I was able to point much higher into the breeze with the 6.0, though.)
Anyway, I think there is definitely something to the type of sail, relating to the ease with which it'll pump in which direction (ie, rotating the mast tip CW or CCW in the pumping cycle), at least for me and my limited skills!
I think I'll be taking the 6.0 out on the local puddle more frequently from now on.
That pretty much matches my experience. Larger sails is more grunt and pull for a few strokes. My small sails I do the "scoop and pull", rotation at the same time increasing the pace until I pop up. Probably 2 to 3x the number of pumps as the small sails don't requirr near the energy IME.