Standup Zone Forum

The Foil Zone => Wingsurfing, Windfoiling, Wingfoiling, Wing SUP => Topic started by: Badger on June 30, 2022, 05:04:01 AM

Title: Foot pressure when foiling.
Post by: Badger 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.
Title: Re: Foot pressure when foiling.
Post by: Caribsurf 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.
Title: Re: Foot pressure when foiling.
Post by: jondrums 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.

Title: Re: Foot pressure when foiling.
Post by: Califoilia 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.
Title: Re: Foot pressure when foiling.
Post by: jondrums 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.
Title: Re: Foot pressure when foiling.
Post by: Badger 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.
Title: Re: Foot pressure when foiling.
Post by: jondrums 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
Title: Re: Foot pressure when foiling.
Post by: Badger 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.



Title: Re: Foot pressure when foiling.
Post by: JohnnyTsunami 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.
Title: Re: Foot pressure when foiling.
Post by: Badger 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?


Title: Re: Foot pressure when foiling.
Post by: jondrums 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.
Title: Re: Foot pressure when foiling.
Post by: burchas 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?
Title: Re: Foot pressure when foiling.
Post by: PonoBill 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.
Title: Re: Foot pressure when foiling.
Post by: Badger 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.

Title: Re: Foot pressure when foiling.
Post by: Badger 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.

Title: Re: Foot pressure when foiling.
Post by: Dwight (DW) on July 04, 2022, 06:58:20 AM
……..if there might be some advantage to having some front foot pressure or if neutral pressure is best.

Neutral (balanced leg) pressure throughout the speed range of your foil is the wholly grail. In practice, you’ll likely get neutral pressure for 80-90% of the speed range, then it’s front foot biased. The thing you don’t want, is that last 20% to be back foot biased. If you do, you’ve got your tail tune wrong. On the flip side, if your front foot pressure increases early in the speed range, you need a smaller front wing.
Title: Re: Foot pressure when foiling.
Post by: Badger on July 04, 2022, 07:35:57 AM
……..if there might be some advantage to having some front foot pressure or if neutral pressure is best.

Neutral (balanced leg) pressure throughout the speed range of your foil is the wholly grail. In practice, you’ll likely get neutral pressure for 80-90% of the speed range, then it’s front foot biased. The thing you don’t want, is that last 20% to be back foot biased. If you do, you’ve got your tail tune wrong. On the flip side, if your front foot pressure increases early in the speed range, you need a smaller front wing.


Great info Dwight!  Thanks.

Now that you mention it, my leg pressure probably isn't precisely neutral all the time. I will look at it more closely next session.


Title: Re: Foot pressure when foiling.
Post by: surfcowboy on July 04, 2022, 07:38:18 AM
Burchas, also tail changes (bigger?) or a longer fuse should stabilize things a bit too. I'm actually borrowing a longer mast to use when working on foot switching just because that and a big tail should make things slow down, pitch-wise, a bit.
Title: Re: Foot pressure when foiling.
Post by: Badger on July 04, 2022, 07:53:29 AM
I'm using the standard fuselage which is pretty long (765mm) and the 440 tail which is also pretty big.

When I see videos of people flying along level and relaxed, I feel like my gear might not be tuned correctly. I'm still a novice though and I'm happy with my progress. I'm also 65 next month so I can't expect to pick it up as quickly as I could have ten years ago.
Title: Re: Foot pressure when foiling.
Post by: surfcowboy on July 04, 2022, 11:21:29 AM
Sorry, Badger I messed up the names.

Yeah then you likely should play with foot/mast position. I'm 55 and took 15 mo to jibe. I feel ya. But it'll come with steady work/play. This stuff is fun, not competitive which I love.
Title: Re: Foot pressure when foiling.
Post by: Wave Chaser on July 04, 2022, 11:39:38 AM
Badger, as a recent beginner I think part of the learning process is learning to be comfortable with what at first feels unstable rather than using gear that takes instability out of the system.  I am also on Axis gear and I benefited hugely from downsizing.  I started on HPS 980 / 420 / and short fuse.  At my light weight it seemed like I would get locked into a trajectory at anything faster than about 13mph (a guess).  Speed induced inertia.  Whether going up until I breached, going down until I touched or pearled, or whether locked into a slow turn, I just didn't have the body weight to make adjustments once the in-motion inertia kicked in.  There is such a thing as too stable, even for beginners.  At slower than 13, I could control it much better, but who wants to go slow all the time?

I felt instantly comfortable on the 830 / P350 / Ultrashort at all speeds except max (Thanks to Lenny at Live2kite for the recommendation).  When I'm fully powered with a deep draft wing and I bear off and sheet in for max speed...then I'm at the limit and I have to concentrate.  But even then if I pay attention I won't wipe out.

So to apply my situation to how Dwight explained it, on the 980 I only had neutral (balanced leg) pressure throughout the bottom 50% of the speed range and I never really felt entirely balanced.  On the 830 / P350 / Ultrashort I feel like I have neutral pressure through 90+ % of the speed range.

Title: Re: Foot pressure when foiling.
Post by: RSeeG on August 07, 2022, 10:15:17 PM
Hi Badger, I have an identical setup except (except for 475P rear wing) and am also starting out.

I started with the Axis base plate at the back of the tracks of the Naish board.  Wanted to move it back a bit more due to the same issues you mentioned so spoke to my local shop.  They gave me two longer screws and washers and I was able to move it back about 15mm using the next set of holes on the base plate.  This allowed me to stand more comfortably where the footstrap holes are on the board with fairly even foot pressure.

So the Axis / Naish combination is fine for me now.  For me a bit more practice seemed to help with foot placement / pitch / ride height.  Managed to clock 25km/h on the BSC1060 the other day... so something must be right  ;D.

Title: Re: Foot pressure when foiling.
Post by: Badger on August 08, 2022, 03:54:56 AM
Hi Badger, I have an identical setup except (except for 475P rear wing) and am also starting out.

I started with the Axis base plate at the back of the tracks of the Naish board.  Wanted to move it back a bit more due to the same issues you mentioned so spoke to my local shop.  They gave me two longer screws and washers and I was able to move it back about 15mm using the next set of holes on the base plate.  This allowed me to stand more comfortably where the footstrap holes are on the board with fairly even foot pressure.

So the Axis / Naish combination is fine for me now.  For me a bit more practice seemed to help with foot placement / pitch / ride height.  Managed to clock 25km/h on the BSC1060 the other day... so something must be right  ;D.


Having the mast all the way back in the tracks was the key to attaining my first long flights, but I only kept it there for a few sessions. It was very back-foot heavy but it gave me a lot more control. Once I got used to flying the foil that way, I was then able to move the mast forward in increments to the KD balance point where my foot pressure was more equal.

Now, by further fine-tuning my foot placement, I'm finding that by moving the mast forward of the balance point and getting my back foot behind the mast, I can still have fairly equal foot pressure and good control. Moving the mast forward makes it a bit easier to get up on foil when underpowered.

The 1060 has been a great foil to learn on and is a great light wind foil. It goes fast in light winds but sometimes feels sluggish with too much lift in higher winds. I'm going to try the HPS 980 to see how that compares.



Title: Re: Foot pressure when foiling.
Post by: MikeLima on August 08, 2022, 09:34:26 AM
Hello fellow WingMainer*, I too had this issue with my earlier 110 L naish hover, and so did Eric. I ended up getting stick on strap attachments, and adding padding up front. But then, I slowly became aware that takuma foils came stock with what I now believe to be over aggressive tails. I now ride a 220 chopped two bumps in, 178 or 13”kd exclusivity even with the 1440, and if I were still in that board I doubt I’d still  have that issue. And, I’m dipping my toes into axis now, and while they don’t ship with specific tails, I think some of them are too big. For example the wake thief package includes a 460 glide(I guess packages do ship with tails), and after some time behind the boat, I found it to be draggy and lifty like takuma in the day. I put the 375p on it and liked it way better, I might negatively shim it too. 
Title: Re: Foot pressure when foiling.
Post by: Badger on August 08, 2022, 10:53:03 AM
Hi Mike, I hadn't considered how my 440 tail might be affecting the ride. Tails are a whole other rabbit hole to do down and now that I have a short black fuselage coming for my 980, I might start experimenting with shims at some point but I'm not at that level yet.
Title: Re: Foot pressure when foiling.
Post by: MikeLima on August 08, 2022, 01:01:58 PM
If I'm not mistaken the Axis shims that came with the bolt set shim positive, so finding a negative lift shim might be harder than getting a smaller tail. I was thinking of putting a toothpick in there since there's a curve, and breaking the ends off but that's not a permanent solution. I might be taking crazy pills, but the AOA on the tails seem a little extreme, even compared to takuma which I'm used to, so it might be worth figuring out. BTW the p375 looks about the same size as my go-to 178 tail. Changing from the 460 to p375 made the foot pressure way more balanced, and allowed the 1150 to turn a bit too! I'm currently trying to get a 325.
Title: Re: Foot pressure when foiling.
Post by: daswusup on August 08, 2022, 04:23:48 PM
I ride strapped. Even foot pressure takes a bit more tuning with straps. However, once dialed, strapped riding, for me, is way more radical than unstrapped, especially with the wider wings like 999/1099. I ride everything on crazyshort and 325. Not everyone may be ready for this set up but when you are, it is way easier to crank radical turns on big wings.
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