Forums > Stand Up Paddle General

Fin setup question

Reply
Created by Cheni123 25 days ago, 28 Apr 2022
Cheni123
9 posts
28 Apr 2022 3:50PM
Thumbs Up

Hello I have sunova one with three fins (central large thruster) with two small ones near.
What would removing the two small ones do? Make it faster? Less stable?
Can i just remove them or will the open housing will create drag?
Tnx

Hoppo3228
VIC, 575 posts
28 Apr 2022 8:26PM
Thumbs Up

Videos worth watching to learn.... yes they are for surfboards, not sups, but same principals apply. You won't notice drag from empty fin boxes.







I guess the most relevant question to ask is why do you want to remove the sides? What are you looking to do or improve?

Cheni123
9 posts
28 Apr 2022 7:26PM
Thumbs Up

Looking to improve speed. Question is whats the main role of the side fins.

Stability? Speed? Other?

colas
4550 posts
28 Apr 2022 9:39PM
Thumbs Up

Removing the side fins will noticeable increase the speed.
People do not think to remove the side fins, but they often are very surprised by the speed gain.

Filing the empty boxes is not necessary, the drag is not noticeable.
You can fill them with some foam strip if it bothers you.

The drawback of removing the side fins is that the board will hold less when banked into a turn, which is not an issue on small waves.
Side fins help just during hard carving turns, otherwise they just add drag.

Cheni123
9 posts
29 Apr 2022 5:35AM
Thumbs Up

Thank you! Much appreciated.

backbeach
NSW, 70 posts
30 Apr 2022 8:07AM
Thumbs Up

Agree with Colas re side fins and manouvres. They really help your board engage the rail through turns suiting contemporary rail to rail surfing. Singles need you to draw out your turns and cos of the speed and less drag and less manouvrability, surf with more glide and flow.
You've got to take different lines and approaches to wave faces and surfing, and adjust your headspace to suit. That's the beauty of it-so many different permutations and combinations.
Your best bet is to experiment and change your fin set up during the same surf sesh. Even take a fin key out with you and take the side fins off out the back after a few waves, shove them down your wetty, and enjoy the experiment/change. Just play around with it and feel it.
You'll really start doing your head in when you look at different styles and sorts of fins and there's plenty of feedback here and elsewhere. We got a saying that if you don't like your board change your fins.

colas
4550 posts
30 Apr 2022 2:12PM
Thumbs Up

Select to expand quote
backbeach said..
Your best bet is to experiment and change your fin set up during the same surf sesh. Even take a fin key out with you and take the side fins off out the back after a few waves, shove them down your wetty, and enjoy the experiment/change.



So true!
If you have a chest zip wetsuit, it creates a pocket perfect to store fins, our ribcage doesnt flex so you do not feel them there.

Try also to keep only one side fin, to feel the difference it then makes turning right or left.

surfershaneA
845 posts
3 May 2022 7:47AM
Thumbs Up

Also depends a lot on the shape and style of both the side and centre fins. If you have a narrow based flexible raked centre fin like A, removing the sides can slow the board down. This style of fin can be aided by having side fins generate more drive creating speed and acceleration. Well worth trying different size side bites v centre. Depending on the board and your goals, you could go anywhere from keeping this big fin with micro bites, or moving on to a proportional regular tri fin arrangement.

On the other hand, if your centre fin is stiffer and has a base with more area like B, it should stand-alone generate a lot of power. With these side fins are unnecessary. The extra drag is likely only to make the board slower and unmanageable. Nevertheless, many people who don't have tree stump thighs like the "twang" they get from a lone big flexible single fin.

Other considerations are the design of the board and your own style. Many boards are designed around the fins. For instance, performance boards typically three and a logger a single. Likewise, are you a power surfer, neutral flow, or still hoping to make the pro division? As the comment above, best thing is to experiment and see what suits the board and you!

grgd
SA, 7 posts
14 May 2022 4:22PM
Thumbs Up

Select to expand quote
colas said..
Removing the side fins will noticeable increase the speed.
People do not think to remove the side fins, but they often are very surprised by the speed gain.

Filing the empty boxes is not necessary, the drag is not noticeable.
You can fill them with some foam strip if it bothers you.

The drawback of removing the side fins is that the board will hold less when banked into a turn, which is not an issue on small waves.
Side fins help just during hard carving turns, otherwise they just add drag.


Colas, I have a Fanatic Stylemaster (10', 145 L), I'm 68kgs and just starting out surfing. I surfed 50 years ago and thought it was time to get back into it :-).

I swapped out the 1+2 fins with a single raked fin (Captain Fin Raked 9.5"). I've only tried this in one session but I found the board to be a bit quicker. It seemed like I was getting onto more waves, but that may have been for other reasons. I was also trying to get my weight forward to project the board down the slope as you describe somewhere else.

But I also found the board harder to turn. Is this just because the single requires more weight on the back foot?

Is there any advantage at all to having the side bites if I'm surfing <3ft waves.

colas
4550 posts
14 May 2022 4:07PM
Thumbs Up

Select to expand quote
grgd said..
But I also found the board harder to turn. Is this just because the single requires more weight on the back foot?


This because by removing the side bites you moved the fin surface center to the aft. Just move the single fin forward to compensate.

My advice is to put your single fin as forward as possible, and move it back a bit if you feel that the board is too squirelly or loses too much speed at the end of turns.

Also, if you want to put back the sidebites to try to perform more modern carving turns, losing less speed in turns than with a single fin, I would advise to get a small center fin, to set the board in a thruster setup (all 3 fins of the same size). This way you will feel more easily the difference between these two setups.

Otherwise, keeping a big center fin with sidebites will help control the board in bigger waves.

grgd
SA, 7 posts
14 May 2022 6:50PM
Thumbs Up

The Captain Fin Raked fin takes up nearly the whole fin box so the front edge of the fin is right at the front of the fin box. The total adjustment range is about half an inch.

The side bites are 4 1/2 inches and that can't change because Fanatic use a non standard fin box. The stock Fanatic centre fin is 8 inches in a US box.I could get a Greenough or similar fin down to about 6 inches. Not sure if I could get anything smaller.

Mark _australia
WA, 21333 posts
14 May 2022 6:02PM
Thumbs Up

^^^ what non standard box? I hate that crap from companies. But their web site shows what looks to be Futures sidies and US box ctr...?

You may find an old windsurf fin in US box, with shorter base that enables more movement fore and aft.

grgd
SA, 7 posts
14 May 2022 7:45PM
Thumbs Up

Select to expand quote
Mark _australia said..
^^^ what non standard box? I hate that crap from companies. But they web site shows what looks to be Futures sidies and US box ctr...?

You may find an old windsurf fin in US box, with shorter base that enables more movement for and aft.


Not futures. It's their own thing.

Mark _australia
WA, 21333 posts
14 May 2022 6:17PM
Thumbs Up

I repeat then - I hate that crap.

colas
4550 posts
14 May 2022 10:05PM
Thumbs Up

Select to expand quote
grgd said..
Tthat can't change because Fanatic use a non standard fin box.



The accept Future fins.

See my post at www.seabreeze.com.au/forums/Stand-Up-Paddle/SUP/Fanatic-allwave-Fin-set-up-2?page=1#2388497

grgd
SA, 7 posts
Tuesday , 17 May 2022 9:23AM
Thumbs Up

Select to expand quote
colas said..

grgd said..
Tthat can't change because Fanatic use a non standard fin box.




The accept Future fins.

See my post at www.seabreeze.com.au/forums/Stand-Up-Paddle/SUP/Fanatic-allwave-Fin-set-up-2?page=1#2388497


Thanks Colas. Yes I was a bit hasty in my comments on the Fanatic fin box.

colas
4550 posts
Tuesday , 17 May 2022 11:39AM
Thumbs Up

Select to expand quote
grgd said..
Thanks Colas. Yes I was a bit hasty in my comments on the Fanatic fin box.


On the other hand, the Fanatic box with its screws on the side may not work well with current future fins that have nearly all an hollowed-out base...

eu.futuresfins.com/en/13-surfboard-fins



Subscribe
Reply

Forums > Stand Up Paddle General


"Fin setup question" started by Cheni123