Author Topic: Foot pressure when foiling.  (Read 8756 times)

Badger

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Foot pressure when foiling.
« on: June 30, 2022, 05:04:01 AM »
Is it best to have neutral foot pressure when wing foiling?  Would there be any advantage to having more weight on a particular foot?  What is your preference?

Right now I have my mast set at the KD balance point. My weight on each foot is more or less equal and the foil feels very stable. Should I expect this to change as I become more advanced?

I'm just flatwater foiling. Not jumping or surfing. Specs are below.
Kalama E3 6'1 x 23" 105L
Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

Caribsurf

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Re: Foot pressure when foiling.
« Reply #1 on: June 30, 2022, 10:59:30 AM »
Hey Badger, I find my foot pressure alternate from front to back during my riding.  I adjust to raise or lower the board/foil..sometimes on a long reach I can just stand planted equal pressure on both feet and go along for the ride, but more times than not I am alternating front foot ,back foot to adjust the foiling height and trying to get a comfortable sweet spot. 

And certainly when pumping during lulls I think I put more pressure on back foot.
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jondrums

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Re: Foot pressure when foiling.
« Reply #2 on: June 30, 2022, 12:15:02 PM »
A lot of people refer to certain foil setups as "front foot" or "back foot" oriented.  In general, Lift is back footed out of the box and GoFoil is front footed out of the box.  Both have prisoner tail systems and unless you invest in aftermarket solutions lock you into their thinking.  In both cases, those setups can be made much "better" by using an aftermarket tail system with the correct shimming to neutralize the system.

So what is back or front footed???  I'll try my best here

The big front foil is responsible for the lift.  The tail foil in the back is responsible for the stability of the system - just like the fletching on an arrow. 

Just like an arrow - the CENTER OF MASS must be AHEAD of the lifting center of the front foil in order for the system to be fundamentally stable.

How to get the CENTER OF MASS AHEAD of the lifting center?  Shouldn't you but right on top of the lifting center?  That's where the tail comes in.  The tail should be pushing DOWN on the system from the rear, which causes a PITCHING MOMENT around the center of lift (pushes the nose UP).  With the tail tuned correctly, your center of mass can be further forward of the lifting center and you get stability!

The further forward your center of mass, the more stable the system.

--------------

A "front footed" foil is one that has a lot of tail downforce putting the center of mass very far forward for lots of pitch stability.  That's really great for learning and allows for a relaxed slower foiling style.  (As a side note, all that tail downforce increases drag, and front footed foil setups don't glide as well)

A "back footed" foil is one that has minimal tail downforce, putting the center of mass further back, and has less pitch stability.  In the extreme, it could be a fundamentally unstable system.  These are twitchy and nimble but require a lot of attention and muscle memory.  Also quite efficient from a drag perspective (some would call it "fast")

After a LOT of experimentation across several brands of foils, I now very much prefer quite a neutral foil which is whatever I personally feel is the best balance of the two.

---------------

It should be noted that different disciplines require different setups.  With a heavy SUP foil board or big wing-board, you'll benefit from a front-footed setup because it helps lift up the heavy board as you unweight for a pump.  With a really light prone board, front footed foils aren't so great.

Another important note here - front footed foils are often tricky to ride across a speed range.  As speed increases you need to shift more and more weight forward.  On a foilSUP wave takeoff, there is a weight shift forward as the board comes up to speed on the drop that needs to be learned.

Back Footed foils are really tricky to ride fast because they are less stable.  Speed wobble is real!

Hope this helps.


Califoilia

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Re: Foot pressure when foiling.
« Reply #3 on: June 30, 2022, 02:49:33 PM »
I think most of all of that is personal preference...I personally set my foil setups to be very front-footed. I prefer having to keep the nose down as I'm flying at speed for several reasons.

1. I want as much lift as possible on takeoff, to get the board off the water asap, and with the HA wings nowadays, that typically means they lift with with speed vs increased pitch like the lower aspect wings did. With that, I need to wait later for the wave to get steeper, and I drop into it more like a "skateboard ramp drop" as I call it, and want full control of the wing and nose of the board (pitch) with my front foot.

2. Having to keep pressure on my front foot when flying, also helps with turning, as I will simply put a little more pressure on the nose as I'm rolling the board over, and I have much more feel of the board as it's picking up speed in the turn, and it's simply a matter of applying or reducing pressure to keep it tracking through the turn level. Once I'm turning back up to the face or towards the whitewater to make my cutback, I simply release almost all pressure, and let the wing release completely as it then starts automatically climbing back out of the turn to get back to height immediately.

3. Being on a standup and with the higher aspect wings, it's almost imperative to have the pressure under my front foot when pumping. This is b/c with the higher aspect wings, we can no longer try to "Ollie" the board up, but have to be able to push the nose down at height just as the glide is beginning to dissipate  to pick up speed, and then almost immediately after that slight push down, I have to get off of the board right away to unweight it to allow the wing to then climb back up to height for the next glide period. If I'm back-footed, and/or further back on the board, I can never get it leveled off quickly enough, or be able to push the nose down to gain the necessary speed the higher aspect wings need to fly/glide correctly.

4. It should be noted that I also ride what had been AXIS's shortest fuse (they just released an even shorter one that I've not throw on my kit yet), and as such the shorter fuses are more pitchy than longer ones, and being on a 5'1 board, the only way I've found to be able to control that pitch is with very subtle adjustments with my front foot holding and releasing pressure with it quickly and somewhat often.

JMO and what I personally do...OMMV as will their personal preferences and feels while foiling.
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jondrums

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Re: Foot pressure when foiling.
« Reply #4 on: June 30, 2022, 03:03:24 PM »
3. Being on a standup and with the higher aspect wings, it's almost imperative to have the pressure under my front foot when pumping.

yes exactly what I was saying too @Califoilia

It should be noted that different disciplines require different setups.  With a heavy SUP foil board or big wing-board, you'll benefit from a front-footed setup because it helps lift up the heavy board as you unweight for a pump.

Badger

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Re: Foot pressure when foiling.
« Reply #5 on: June 30, 2022, 05:16:43 PM »
Thanks for the replies.

As expected, it's a lot more complicated than I thought with many variables to consider.

I did find it easier to get up on foil with the mast all the way forward but riding that way was very front-foot heavy to counteract the increased lift.

I think I'll stay with my current setup until a need to change it presents itself.
Kalama E3 6'1 x 23" 105L
Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

jondrums

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Re: Foot pressure when foiling.
« Reply #6 on: June 30, 2022, 06:25:10 PM »
well that's not really what front-footed means.

If you move your foil forward in the tracks, you should move your feet forward on the board the same amount.

Its not the position in the track that makes it front or back footed, its the tail shim/angle

In practice these two things are somewhat interchangable - can always move your feet to feel more pressure on front or back foot, but it isn't what the general use of the term "front footed" is typically used to describe in my opinion

Badger

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Re: Foot pressure when foiling.
« Reply #7 on: June 30, 2022, 07:39:12 PM »
well that's not really what front-footed means.

If you move your foil forward in the tracks, you should move your feet forward on the board the same amount.

Its not the position in the track that makes it front or back footed, its the tail shim/angle

In practice these two things are somewhat interchangable - can always move your feet to feel more pressure on front or back foot, but it isn't what the general use of the term "front footed" is typically used to describe in my opinion


I wasn't talking about front-footed. That was your phrase.

I did adjust my stance when I moved the mast forward but did not want my front foot to be forward of the deck pad because that didn't seem logical. I should try that just to see how it affects front foot pressure not that I would want to ride that way.

My original question was whether there was any advantage to being front foot heavy or back foot heavy. Caribsurf and Califoilia addressed that to some extent.



« Last Edit: June 30, 2022, 07:48:31 PM by Badger »
Kalama E3 6'1 x 23" 105L
Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

JohnnyTsunami

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Re: Foot pressure when foiling.
« Reply #8 on: June 30, 2022, 09:27:57 PM »
I have a tuttle and can only adjust my front footstraps. I have it so it's even leg pressure at slower speeds and I lean back slightly to take off. At my highest speeds possible I've got most/all of my weight on my front foot. I don't think anyone rides back foot heavy most of the time or they would be nose diving on every transition.

Some foils have a wide window of how far your weight needs to move. I think that's what the other person is saying. Some wings you only need to shift your weight forward slightly from your slowest to fastest speeds. Any faster and the foil doesn't need additional front foot pressure. Others, the faster you go, the more forward pressure you need, so the area on your board you need to cover is wider. For instance I have two 10AR planes. One foil is 25% smaller than the other but continuously needs more front foot pressure as speeds increase - far more than the bigger foil. The bigger one with the smaller tail hits an equilibrium where more speed doesn't require any more front foot pressure.

I think this is due to tail design. If you don't need further front foot pressure as speeds pick up, then the tail may be too small and foil is "unstable" at higher speeds. I put that in quotes because I'm not sure that it's true, but I think it's common knowledge. (citing axis guy's blue planet interview and blue planet interview of unifoil).

When I put my straps too far forward (aka back foot pressure), my top end is more comfortable, but I find myself touching down more. Footswitches, slow transitions, ripping turns on waves are all areas you need to lean back potentially (especially ripping turns) and where it may be difficult if you are too far forward. That's why I say nobody rides like that, you can't transition unless you move your feet back. 

For those reasons, aside from slow riding, my rear leg is usually locked and I'm doing variations of leaning on my front foot. If I have to lean way back I'm about to eat shit or i'm doing some quick maneuver. 

The other reason I think is that leaning back is just more awkward while maintaining balance.

Badger

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Re: Foot pressure when foiling.
« Reply #9 on: July 01, 2022, 04:16:17 AM »
I have a tuttle and can only adjust my front footstraps. I have it so it's even leg pressure at slower speeds and I lean back slightly to take off. At my highest speeds possible I've got most/all of my weight on my front foot. I don't think anyone rides back foot heavy most of the time or they would be nose diving on every transition.

Some foils have a wide window of how far your weight needs to move. I think that's what the other person is saying. Some wings you only need to shift your weight forward slightly from your slowest to fastest speeds. Any faster and the foil doesn't need additional front foot pressure. Others, the faster you go, the more forward pressure you need, so the area on your board you need to cover is wider. For instance I have two 10AR planes. One foil is 25% smaller than the other but continuously needs more front foot pressure as speeds increase - far more than the bigger foil. The bigger one with the smaller tail hits an equilibrium where more speed doesn't require any more front foot pressure.

I think this is due to tail design. If you don't need further front foot pressure as speeds pick up, then the tail may be too small and foil is "unstable" at higher speeds. I put that in quotes because I'm not sure that it's true, but I think it's common knowledge. (citing axis guy's blue planet interview and blue planet interview of unifoil).

When I put my straps too far forward (aka back foot pressure), my top end is more comfortable, but I find myself touching down more. Footswitches, slow transitions, ripping turns on waves are all areas you need to lean back potentially (especially ripping turns) and where it may be difficult if you are too far forward. That's why I say nobody rides like that, you can't transition unless you move your feet back. 

For those reasons, aside from slow riding, my rear leg is usually locked and I'm doing variations of leaning on my front foot. If I have to lean way back I'm about to eat shit or i'm doing some quick maneuver. 

The other reason I think is that leaning back is just more awkward while maintaining balance.

Yes, I think I'm starting to understand now. That was helpful.

I'm guessing that tuttle placement is set where the designer might assume the KD balance point would be for the foils he expects will be used on that board.
Then you adjust your stance around that.

The mast tracks make it a little confusing because moving the foil forward or back has a big effect. Moving the mast forward of the balance point makes lift-off easier in light wind but also requires more weight on my front foot when foiling. Too far forward and it becomes difficult to keep the foil in the water at high speeds. It's a trade-off. This is probably more noticeable on bigger boards.

Does this make any sense or am I way off?


« Last Edit: July 01, 2022, 05:05:21 AM by Badger »
Kalama E3 6'1 x 23" 105L
Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

jondrums

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Re: Foot pressure when foiling.
« Reply #10 on: July 02, 2022, 11:07:27 AM »
The mast tracks make it a little confusing because moving the foil forward or back has a big effect. Moving the mast forward of the balance point makes lift-off easier in light wind but also requires more weight on my front foot when foiling. Too far forward and it becomes difficult to keep the foil in the water at high speeds. It's a trade-off. This is probably more noticeable on bigger boards.

Does this make any sense or am I way off?

yes, exactly.  There are so many variables and it sounds like you are getting the feel.  No substitute to trying things - I feel like I never go more than a few sessions without changing something - eventually you get to where you know what you want to change to get the feel you want.

burchas

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Re: Foot pressure when foiling.
« Reply #11 on: July 03, 2022, 11:54:09 AM »
starting to understand now. That was helpful.


Badger, what mast length are you using for light wind?
in progress...

PonoBill

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Re: Foot pressure when foiling.
« Reply #12 on: July 03, 2022, 02:18:59 PM »
It has become foil gospel that moving the foil forward in the tracks increases lift and moving it back increases stability. Like most gospel, at best it's oversimplified and at worst it's nonsense. Most of the change in feel and performance characteristics from moving the board in the tracks has to do with the nature of the board. If you move the foil forward an inch and move your foot position forward an inch the only difference is in the board dynamics. If the board can be stood on comfortably with your feet in the new position then you really won't feel much of anything at all. I pay almost no attention to the foil position with my old Flying Dutchman because it floats comfortably with my feet in the required flying position regardless of where the foil is positioned. If you have to shift your feet from the static floating position to the dynamic flying position then you're likely to have some interesting experiences.

If you want to experiment with foot pressure changes the easiest way is by shimming the tail wing. I shim my tail to enable me to trim the foil comfortably with my feet fairly close together. I switch feet in the middle of jibes and tacks, so a more relaxed stance with my feet at shoulder width is a benefit. Most beginners are in a stinkbug pose, so trimming to neutral pressure is difficult.
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Badger

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Re: Foot pressure when foiling.
« Reply #13 on: July 04, 2022, 03:56:56 AM »
starting to understand now. That was helpful.

Badger, what mast length are you using for light wind?


75 centimeters.

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Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

Badger

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Re: Foot pressure when foiling.
« Reply #14 on: July 04, 2022, 05:08:54 AM »
I'm starting to think it might be the Axis foil/Naish board combination that is giving me trouble. With the mast all the way forward in the tracks, to equalize foot pressure, my front foot would need to be so far forward that it would be completely off the deck pad. With the mast all the way back, I need a lot of wind to get up on foil regardless of where I have my feet.

With the mast set at the KD balance point, I can have equal foot pressure. My front foot is right where the front foot strap would be if it were mounted all the way forward and my back foot is over the leading edge of the mast just forward of where the rear foot strap would be. My feet are slightly off-center for stability. My front foot is a little to windward and my back foot slightly downwind of the centerline although I would like them to be more centered at some point. I try to stand up straight in line with the mast when foiling, leaning back slightly into the wind.

Foiling with equal foot pressure is okay but it seems somewhat sensitive to my weight shifting when controlling altitude. I sometimes find myself getting too high or touching down, especially at higher speeds. This is where my original question came from. I wanted to know if there might be some advantage to having some front foot pressure or if neutral pressure is best. It could also mean that I just need more practice.

Another theory is that the BSC 1060 is a large foil which might cause it to be lift sensitive. Maybe downsizing to the BSC 970 might be a good idea.

I'm thinking of going to an 82 centimeter mast but I also have to consider that most of the places I foil get shallow as the tide goes out.

« Last Edit: July 04, 2022, 05:32:10 AM by Badger »
Kalama E3 6'1 x 23" 105L
Axis HPS 980 / PNG 1300
Sunova Flow  8'10 X 31"  119L
Me - 6'0" - 165lbs - 66yo

 


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