Prone Board Length

I have a 4’2 prone board that is 32 liters which floats and paddles perfect. I have been focusing on narrowing my stance as much as possible but it is either the board length or too much lift preventing me from getting any narrower. Tail shims seemed like they helped reduce a little of the lift for more of a relaxed stance.

But I wanted to know what your guys thoughts were on board length. Would an extra 4" of board narrow my stance up some?

FWIW I have a 38L 4’6 and today I was practising pumping with my feet nearly next to each other. Key is edging front foot slowly back while edging back foot slowly forward. I don’t think the board should play into it that much in terms of actively forcing a narrower stance, I manage the same on my smaller kiteboard for dock start.

My guess is getting the tail shim setup properly dialled to keep reducing the lift so that you don’t pump the nose up and down, rather just pulsing/tapping the board straight down. Only once I’m doing a nice flat pump can I bring my feet together, and I generally find they end up just ahead of the mast, above the front wing centre of lift, which makes sense.

To really get into it, I don’t think it matters so much narrowing your stance as getting your weight over the centre of lift? The whole setup will be the most efficient and balanced when the CoG is right above the CoL. Though I suppose probably once you are above the CoL, narrowing your stance will improve the efficiency of your muscle movements…

(I drew this diagram in another conversation that maybe illustrates it somewhat)


Thanks Matt. That’s really good insight. Seems like I just need to shim more. My pumping is definitely more up and down rather then pressure taps like I want it to be.

1 Like

What about Adam, going smaller

1 Like

Yeah, this is an interesting topic that I’ve been struggling to wrap my head around.

Recently had an irreparable box failure on a 4’2” FFB and picked up a 4’0” FG armie board to keep me in the water while waiting on a more drawn out 4’3” custom. Always thought the armie board would turn into a reliable backup…I’m now trying to dial in a 4’3” custom Amos Spitfire (24.6 L) and every time I feel like I’m getting settled into the sweet spot, I look at my stance and feel like…I’ve got 12-14” of unused tail that seems pointless. The pulled in tail makes sense to avoid contact during deep carves, but…seems like having no tail to make contact would work even better. Still undecided and need a few more sessions on the amos, but right now it feels like my turns are a lot crispier and I can drive harder into turns with a lot more confidence on the armie setup.

@Erik - I know you’ve mentioned digging the counterweight that the extra tail length provides - can you speak to that a little?

Just got me a custom spitfire too (4’4” 30L). I was drawn to it cause of it’s forward box position. My cab H800 was at the front of the box on my 4’2 30L from a local shaper.

Still trying to figure out the mast and foot placement on the spitfire. The forward volume and drawn out tail makes things interesting paddling and placing the feet. I probably coulda gone with a few less liters as it feels and paddles bigger than my other 30 L board.

With you 100%.

I’m on lift gear and was finding myself resorting to baseplate shims, etc on other set ups to get the front foot feel where I like it and just wanted something built with that gear in mind (also why the extra track length of the Armstrong was appealing).

I’m shocked at how much more volume it feels like…at <25L it paddles better than 30L boards. Could have come in a little thinner I reckon. Finding that a little more tail shim (less lift) helps to dial in the balance point - also certain that the flat deck is taking some time to get used to. Zane and Rhett are killing it, so I’m sure there’s more to unlock. Just a bit less intuitive than any other board I’ve been on…

Hey Chris - for what it’s worth, finally hit the right tune on the spitfire today. Setup is absolutely mental. For me it just took a bit more tail shim (less lift) to balance out the forward mast position. Well worth the time to dial it in.

Nice, I’ll try mast forward shim back of the tail more next time I’m out. Thanks🤙🏽

Hi SdCliffsFoil,
IMO simple answer is nope… If the goal is to narrow your stance you need a smooth stable ride. So very dependent on the foil setup rather than the board. Longer fuses are smoother less pitchy, easier to ride. Riding the tail as neutral as possible will make things less pitchy (and faster) but may require more skill because you have to angle the foil yourself.
I’ve been making board for myself and others and generally the simplest advice for a board is the stiffest, smallest board you can get up to a speed that your foil engages is the best… length & width are trade-offs for catching waves and getting on foil vs performance.

My new board is 4’6 but much narrower than previous (4’3 x 19 - 30L), my new one is 4’6 x18 - 29L, it feels great. I like it better for doing turns and hitting white water.

Thanks NorthEastFoiler. Playing around with tail shims to make the foil feel neutral has helped a lot. I also think I need to get another front wing with less surface area for the days when there is more size.

1 Like

Re: the 12 inches of board hanging off the back I recently ordered a spitfire from Amos with the tail cut off completely. It’s a 3’3 which I wanted just for dockstarts / flatwater but if goes great behind the boat too. I’ve yet to try it in the surf but I actually think it’ll work. Will let you know how it pans out.


That is a rad little flying machine you’ve got there! Really curious to hear how it goes in the surf - keep us posted for sure.

I’ve really fallen in love with the spitfire now that I’ve got it tuned properly. It’s blowing my mind how quick and responsive it is. Went back to the Armstrong for a session and everything felt way laggy in comparison/needing a much heavier foot.

Do you find the rail-to-rail is still super sensitive/responsive with the snub-tailed version? What foil setup are you running on it?

1 Like

How’s the tuning going?

Seems like the cab 800 runs similar to the lift 120 in terms of mast placement. My current 120 tune is:

NoLimitz 78cm mast at about the 3.5 mark (if the farthest back line is considered 0), Takuma 158 tail with 1 degree shim on the 11” Stueber tail adapter. :ok_hand:t3:

Curious to hear how you’re liking the board!

I’ve been using it with a variety of different Signature foils depending on what I’m doing from the Albatross 165/210/250 for pumping to the Game Changer 170 behind the boat. It was riding it behind the boat that made me think it’d be awesome in the waves if I could paddle in OK (it’s 19l) as it’s super responsive. It’s been flat for a while but as soon as we have some surf I’m giving it a crack.

Really interesting to hear on the Spitfire. I have a 4’6 Raptor which I love for prone. Have you ridden one of those? Would be interested to know how they compare…

I don’t - this is my first Amos setup and I’m probably going to end up a long-term convert, assuming the love affair continues. I have heard others coming off the raptor say that they really love the spitfire.

Let us know how she goes in the surf!

You always need more foils!

1 Like