After following the foil development for a couple of years I finally decided to give it a go this spring.
A bit of background. I have been windsurfing for 38 years, mostly on slalom gear but also in waves, 52 years and around 90 kg. I decided to start with a low aspect foil following advice that this would give a faster learning curve. I also wanted a modular system where I could add more fuselages and wings in the future, and a stiff carbon mast in a good length which I would not outgrow anytime soon. My short list consisted of F4, Lokefoils and AFS. I decided on F4 based on their long history in windsurf foil development in combination with their wide choice of wings and fuselages for both maneuver and race oriented foiling.

Contact and delivery Asking for advice on the F4 website on which wing type and size to choose I received advice directly from F4 designer Chris. This was much appreciated, and I hope they can keep this up in the future. It really makes a positive difference to get advice from someone with a deep knowledge of their products. Living in Europe I ordered a F4 freeride foil with carbon mast and tuttle head from one of the European retailers back in May. After consultations between the retailer and F4's European distribution center I was told that delivery would take 2 weeks. After numerous follow ups and new promises on delivery within further weeks, I started thinking about cancelling my order and taking my business elsewhere. I hope F4 get their European distribution sorted out, it was not a good experience in my case. Finally by mid July, after around 10 weeks of waiting, I received the foil.

Product quality and dimension The carbon mast feels very solid and stiff (2,65 kg) with 97 cm length. Also the fuse and wings look good. The front wing is 1400 cm2 and 77,5 cm wide. Stab is 228 cm2 and 42 cm wide. Fuselage 85 cm, and total distance from leading edge of the front wing to trailing edge of the stab is 91 cm. Everything fits well together with 3 M8 torx bolts for the front wing and M6 bolts for the stab (2) and fuse (3). It comes in a nice padded back with space for additional wings, stabs and fuzes. Finishing on the foil is generally very good, expect for some excess laminate from the mast overlapping the first part of the tuttle head. It took a bit of grinding to correct before the tuttle head could be inserted fully into the box of the board.

Trim I have mostly used the foil on a Fanatic Falcon Slalom 136. Foot straps placed as I use the board with fins for the simple reason that I don't want to spend time moving foot straps around between sessions: Back straps second hole from the back, front straps in the back holes. It might have provided a more secure stance if I had moved the front foot straps further forward for a wider stance.
So far I've found that mast foot placement at 113-115 cm from center of front foil bolt to center of mast foot gives a good balance depending on how powered up I am. Lighter winds, mast foot further back. I have also found that I can easily use a sail 2,0-2,5 m2 smaller than what I would use with a fin. Most used sails so far are a 5.8 wave sail (North SuperHero) and a 6.6. freeride sail (North e-type) in winds from 6 to 9 m/s.

On the water First time out on the foil with a 5.8 wave sail I got lift off right away after a few pumps in winds around 13-16 knots. What an amazing feeling! But also scary due to the hight and lack of muzzle memory for pitch control. Felt like learning to ride a bike again - muzzles stiffening up, balance adjustments coming too late and once coming, overadjusting. Very insecure feeling in the beginning but also very exciting to learn new stuff.
I have now had 10 sessions with the foil since mid July and feel much more relaxed in flight. Micro adjustments to balance the foil are beginning to come in a more natural way. I have started practicing jibes and getting very close to nailing my first jibe without touching down. Next session!
The F4 freeride foil is a very well behaved foil which is easy and fun to use and has made it easy for me to progress on without having serious crashes. It goes upwind pretty well and better than a fin, but not as well as I expected. Maybe I need to be more powered up to achieve tighter angles. A board with a wider tail would also help. I am using both foot straps most of the time except when going downwind. Downwind I usually only use the front strap and if I feel overpowered it can feel more safe to have the front foot just inboard and in front of the front foot strap.
As for speed, I normally reach a top speed of around 17 knots without being very powered up and without trying to push for speed. This speed on the foil gives me the same level of nice thrills as doing 27 knots with a fin in choppy waters. I am pretty sure the F4 freeride foil can go faster if pushed. Would be interested in hearing which speeds other users of this foil model can achieve Minimum wind to get foiling for me is currently around 6 m/s (11 knots) with a combination of sail and foot pumping. In lulls it is easy to pump the board/foil to fly through. For the coming sessions I will experiment with swell riding and pushing for more speed to get to know the foil better. So far the F4 freeride foil has been a both pleasant and exciting experience!

My experience is that you want to be really powered up to go really upwind (also sail trim is important). Of course the aspect ratio of the foil and the type of sail and board will dictate how much upwind you can go but this is generally true with very low and very high aspect ratio wings and everything in between.
I am glad you are having a good experience!

Good honest review thanks for sharing

I have the exact same mast and also had a small amount of excess laminate on the tuttle head

I think you should consider getting a dedicated foil board very soon, it will make the journey more enjoyable
There are many board options so seek advice from others in your local area on brand, at 90kg you would want a board about 150L / 90cm wide

Keep pushing and give us an update in a few months

Enjoyed reading your review. Tonyk nailed it. You're about due for a full foil board. The wider tail will let you get outboard more and sheet in which will help your upwind ability. Touchdowns will likely be easier as foilboards have more v in the nose and set down easier than a slalom board which can be pretty flat up front. It's not necessary and I have foiled in higher winds with a 125l slalom board. But the deck shape, width in the back, etc all start to make a difference.

And, like tonyk, looking forward to your update.

Hi, can you tell us the total weight of yor f4 foil set?

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BSeeSurf said..
Hi, can you tell us the total weight of yor f4 foil set?

I have a race set but can help you with weight of a few components to give you a general idea
Carbon HM Mast 97cm 2021 with fixings - 2.8kg (the mast that comes with freeride foil)
Fuse 90cm with fixings - 1.45kg
Race Stab 230cm2 - 0.175kg
Race Wing 945cm2 - 1.0kg
So around 5.5kg all up
Bear in mind this is a very stiff mast and wings, so to achieve this a of lot material has to be used, many other brands have lighter masts,
(where I sail we call these light carbon ones 'The Cheese Mast' )

I recently got an F4 Freeride setup to replace my Slingshot i76 and am really struggling with the F4. It seems like it just doesn't want to ride level.

With no shims and everything else the same as the Slingshot, I seem to need too much back-foot pressure to get it flying. But, when I slow down to almost stall speed (crappy jibe or when coming to a stop), it wants to pitch up to something like 20-30 degrees before eventually stalling. It's actually quite impressive how slow it will go without stalling, but it's very difficult to control in this pitch-up mode, so I'd prefer it just stay level. Also, if I go to head downwind (or jibe), I have a difficult time keeping the nose up when I take my back foot out of the strap. But, if I lose too much speed and get close to stalling, it suddenly wants to pitch up.

I've tried a shim to give the stabilizer more angle. This helps alleviate need for back foot pressure, but it doesn't help with the slow speed pitch-up behavior. Moving the foil forward in the track seemed to do the same.

Anyone have some tuning tips for me? Or, is it just TOW to learn it. I do have close to 200 sessions on the Slingshot (i76 and i65) so it's possible I'm just so used to the SS behavior and need to learn the F4.

The big elephant in the room is this: is it balanced? In other words, is the front wing somewhere near to the middle between front and back footstraps? Since you mentioned needing too much back foot, I would guess the wing is too far aft.

Try to move the foil forward (or footstraps back) without messing with shims. You can also move the sail mast base back.

The reason you did not experience this with the i76 is that the i76 wing has a very broad center of lift. It is very forgiving of position and works fine even when out of "balance." Also, compared to the F4, the i76 will have a very mushy stall, to the point where you don't even notice the stall.

Then, of course, the main thing is to get a lot of time on the new foil. Also, the F4 definitely requires you to keep the hammer down and keep the speed up. Slowing down and riding nose high is just a stall ride. Push the nose down, sheet in, and go hard. The faster you go, the more the balance point will shift forward.

I have exactly this same situation with my gear in Florida. i76 and AFS-2 under a Exocet FF132. The box is deep tuttle, so I can't move the foil, but I can move the footstraps and mast base position. The AFS-2 requires much more back foot but feels balanced at higher speed. Jibes? I am perfectly happy to come down off the foil and make a windsurfing planing jibe on the water.

Thanks. I'll definitely try moving the track forward.

I'm a little suprised to hear the F4 requires you to keep the hammer down, as it's shape looks very similar to the i76. And, it's not a fast wing, especially compared to the i65. OTOH, it is rock solid. The i76 wobbles and shakes, and the difference in the F4 is enormous. But, I was hoping for a friendly, turny ride that jibes easy, can go slow to play around in swells and can help me finally get a full foiling downwind 360. This is not that foil?

BTW, also have the F4 slalom setup. I'm loving that. I'm a little scared of it, but that's part of the fun. The only issue is the big crashes when it finds one of the abundant cownose rays we now have up in the Chesapeake.

I have had around 30 sessions on the F4 Freeride since July last year. It was my first foil and I have not tried other foils so I cannot compare. The trim i have found to give good pitch control on the F4 is to have the boom at chin to nose hight, keep the back leg pretty straight and the forward leg slightly bend while leaning a bit forward to be able to easily adjust my weight through front foot and mast base by shifting the weight more/less forward as needed to control the pitch. I run the mastbase at 106-107 cm from the front tuttle bolt.

I find it quite stable and friendly also at slower speeds, only at very slow speeds going downwind (in a lull) I have also experienced that it pitches up as you describe. But I think this is just its stall behaviour? To avoid it, just keep a bit more speed while on the foil and push the board down to the water surface if speed is dropping too much before the foil starts to fell wobbly.

As for playing around in swell, that is also one of my intentions with this foil, and I think it will be game. I am not yet experienced or courageous enough to play around wavesailing style in swell (still practicing wide s-maneuvers), but I do feel it has the potential to take much tighter maneuvers.

I have also experimented with shims but have gone back to using no shims because it works just fine without shims.

Still a lot to learn for me, but enjoying the ride a lot!

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US85 said..
I'm a little suprised to hear the F4 requires you to keep the hammer down, as it's shape looks very similar to the i76. And, it's not a fast wing, especially compared to the i65. OTOH, it is rock solid. The i76 wobbles and shakes, and the difference in the F4 is enormous. But, I was hoping for a friendly, turny ride that jibes easy, can go slow to play around in swells and can help me finally get a full foiling downwind 360. This is not that foil?

it can be.

as segler suggested, the foil may not be balanced in your setup at the moment. once you achieve that balance and maybe a slight bias to the front foot, it should get you to those goals; and no, you won't need to keep the hammer down - it can ride depowered very nicely and has a pretty low stall speed that should keep you flying as you work thru manoeuvres. do be aware that, as noted, when switching from powered up to depowered mode it will try to ride up, but also level up roll-wise. it has never breached on me when doing that.

also please note that this foil was originally developed with a 340cm stab; at some point F4 started to ship it with a 228cm stab, which (without changing any other settings or using shims) does want more back foot pressure. i personally enjoy the foil most with the 228 stab, as it really makes the foil lively and free, but in very light winds or when under-sailed, i prefer the 340 stab (i ride the Tuttle version, so no chance to move it forward on tracks). perhaps i should check with F4 if they have some power-adding shims (my set had no shims).

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Watatait said..

As for speed, I normally reach a top speed of around 17 knots without being very powered up and without trying to push for speed.

I am pretty sure the F4 freeride foil can go faster if pushed. Would be interested in hearing which speeds other users of this foil model can achieve.

with the 228 stab, 17kts is a happy cruise speed for this foil (vs. ~14-15 with the 340 stab).

it can be pushed to upper 19s, low 20s over ten seconds without a lot of effort (but that's not really what this foil is about).

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Watatait said..
As for playing around in swell, that is also one of my intentions with this foil, and I think it will be game. I am not yet experienced or courageous enough to play around wavesailing style in swell (still practicing wide s-maneuvers), but I do feel it has the potential to take much tighter maneuvers.

this:

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Paducah said..
...Tonyk nailed it. You're about due for a full foil board.

agree totally. a dedicated foil board (not a freerace-oriented one that is) should get you the carving, swell-riding, and tight turning the foil can deliver.

best luck!