Author Topic: Advice needed on quad fin setup for a 2018 Blackfish  (Read 10159 times)

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Advice needed on quad fin setup for a 2018 Blackfish
« on: July 10, 2018, 06:40:42 AM »
So I have bought a few weeks ago a 2018 14' x 25" Infinity Blackfish. The main reason for the choice of board was that I wanted to try the Larry Allison four fin setup which the Blackfish has a factory option. Included in the deal was supposed to be a set of Larry Allison fins to match.

The board was delivered instead with a set of Stavron fins. The main issue is that the Stavron side fins have FCS tabs but the board has powerbox boxes. The powerbox canted inserts were not delivered with the board so I cannot install any side fins at the moment. Also, the Stavron ventral fin, despite the box is marked "Stavron", does not fit in the box as the base it's too thick and I would have to hammer it in place.

According to the dealer this year Infinity has switched from Larry Allison to Stavron fins, but for some reasons my board has still powerbox boxes, maybe the factory did a mix and match of whatever boxes they had left in stock?

I have followed the many post about the Larry Allison setup and would like therefore use his fins, but I am based in Brisbane Australia and cannot find anyone selling the L.A. fins anywhere in the whole country. The dealer has been promising me for ages to get me the right L.A. fins "next week" but I am starting to lose confidence that this will ever happen.

Can anyone help me to work out exactly which fin set is right for my board and where I could get it from? TIA

Bean

  • Cortez Bank Status
  • *****
  • Posts: 4211
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #1 on: July 10, 2018, 07:28:30 AM »
When you say powerbox, are you referring to LA's ProBox?

Bean

  • Cortez Bank Status
  • *****
  • Posts: 4211
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #2 on: July 10, 2018, 08:01:59 AM »
FCS fin bases actually do work well in the ProBox fin box system, so it sounds like you might just need the correct inserts.  The ProBox system is pretty scarce on the east coast US too, but it is a great system. 

Your ventral fin base might just need to be sanded down a bit.  A simple sanding block with 100 to 220 grit sand paper, while keeping everything square and even on each side should do it.  Just keep in mind that sometimes when a board is hot, (say in transport or right out of storage) the fin box will be really tight until it cools back down. So, if you decide to sand the ventral's base down, make sure you fit it to the box while it is cool otherwise it will end up too loose once it gets in the water.   

No one should have to jump thrugh hoops on a new board purchase, but it does sound like your situation is very salvageable.

FloridaWindSUP

  • Sunset Status
  • ****
  • Posts: 335
  • Marine Biologist, Riviera Paddlesurf Ambassador
    • View Profile
    • James' Blog
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #3 on: July 10, 2018, 09:14:02 AM »
I'm not sold on the LA fins and the four fin setup. I've never seen someone actually be fast on it. I've just seen slow paddlers spend a lot of money on endless varieties of the fins and spend a lot of time bs'ing about how the fins make them feel while they're still paddling slow as turtles. I think the LA fins are good for fin salesmen and for people who collect fins like they collect stamps and comic books. 
14x23 Riviera RP
14x27.25 Fanatic Falcon
11'8 Exocet WindSUP
10'4 Angulo WindSUP
...and a bunch of windsurf stuff

Bean

  • Cortez Bank Status
  • *****
  • Posts: 4211
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #4 on: July 10, 2018, 10:01:11 AM »
I wish I was as fast as a sea turtle...and, as good looking!

The multiple fin arrangement, like on any other simply provides more options. 

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #5 on: July 10, 2018, 06:55:14 PM »
Yes sorry I meant probox. It was past bedtime when i posted. :-)

I did start sanding down the ventral base but then I thought that not knowing if the fin is too wide or the box too narrow, it would be better to wait for the Larry Allison fins to arrive to make sure I sand the right part......

What bothers me the most is that I’ve made very clear to the dealer that I was buying that board from him specifically because it had the 4 fin boxes and because he included the fins in the price. I would have probably bought a different board otherwise, or a 2017 blackfish from a different shop for 33% less than what i paid for his, but he promised that he could get me a set of LA fins within few days so took the plunge on that.

I appreciate that maybe I will never get to the point of noticing any appreciable difference in performance between single and quad fin setup, but Moreton Bay is strongly tidal, and sometime two inches difference in fin depth can make the difference between having to carry the board from/to the shore for 100 metres or not, hence my intention to try the 4 smaller fins setup.

Also, the Stavron centre fin seems to be almost a full size fin, so adding the side fins, which seem also big compared to the LA, would probably slow down the board considerably.

By the way, is the flat side of the side fins supposed to face inboard or outboard on a race sup?
« Last Edit: July 10, 2018, 07:09:59 PM by Ripple »

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #6 on: July 10, 2018, 07:05:06 PM »
Photos attached

Luc Benac

  • Teahupoo Status
  • ******
  • Posts: 1872
  • Super Natural British Columbia
    • View Profile
    • When not paddling...
    • Email
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #7 on: July 10, 2018, 07:54:10 PM »
Best if you put your photos in JPG instead of pdf that need to be downloaded. Less chance to pass on a nasty bug.
Sunova Allwater 14'x25.5" 303L Viento 520
Sunova Torpedo 14'x27" 286L Salish 500
Naish Nalu 11'4" x 30" 180L Andaman 520
Sunova Steeze 10' x 31" 150L
Blackfish Paddles

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #8 on: July 10, 2018, 08:12:20 PM »
I was wondering why they would not show on the post.... will do.
« Last Edit: July 10, 2018, 08:26:42 PM by Ripple »

FloridaWindSUP

  • Sunset Status
  • ****
  • Posts: 335
  • Marine Biologist, Riviera Paddlesurf Ambassador
    • View Profile
    • James' Blog
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #9 on: July 10, 2018, 08:56:50 PM »
Flat side supposed to face outboard on race sups (opposite of how it is on surf sups).
14x23 Riviera RP
14x27.25 Fanatic Falcon
11'8 Exocet WindSUP
10'4 Angulo WindSUP
...and a bunch of windsurf stuff

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #10 on: July 10, 2018, 09:13:54 PM »
Flat side supposed to face outboard on race sups (opposite of how it is on surf sups).

Thanks!

TallDude

  • Cortez Bank Status
  • *****
  • Posts: 5714
  • Capistrano Beach
    • View Profile
    • Email
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #11 on: July 10, 2018, 10:23:44 PM »
Mark Stavron hand makes most of his fins. I have a number of them. He's designed hundreds of fins and his fins have been mass produced by others. I stopped by his shop to pick up some fins for a board I made. The fins were all a little to tight so he sanded them down by hand right in front of me. He got them to fit perfectly. I so many different fins and fin boxes, but the ones Mark sanded to fit are the best fitting setup I have. 
I'd rather sand them to fit, than jamb some tape into the boxes to stop the rattle.
It's not overhead to me!
8'8" L-41 ST and a whole pile of boards I rarely use.

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #12 on: July 11, 2018, 03:02:11 AM »
I'm not questioning the quality of the Stavron fins, it's just that the side fins don't fit without inserts, and the 3 rear fins to me seem too big to be used all three together, as the central on its own is almost a full size single.

Also, before sanding the fin, I want to make sure that is the fin base which needs sanding, not the box.

Bean

  • Cortez Bank Status
  • *****
  • Posts: 4211
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #13 on: July 11, 2018, 06:13:59 AM »
Ripple, your board is designed to be run as a single, single plus ventral, twin, or twin plus ventral.  That does not mean that you couldn't experiment with other combos and fins for that matter.

The ventral box should be the same width as your center box.

A few years ago when I was playing around with LA twin fin system, with Larrys guidance, I added a ProBox twin system and made my own fins.  The twins worked great.  On flat water with the flat side out the board tracked as well as the big factory single but handled side wind much better.  In surf, with the flats turned in, is was a real novelty ride.  That's a board I wish I still had. ;D

« Last Edit: July 11, 2018, 06:16:12 AM by Bean »

Ripple

  • Waikiki Status
  • *
  • Posts: 32
    • View Profile
Re: Advice needed on quad fin setup for a 2018 Blackfish
« Reply #14 on: July 11, 2018, 06:49:00 AM »
Thanks Bean for the advice, testing all the possible combinations is the plan as soon as I manage to get hold of probox inserts. Do you have by any chance the dimensions (lenght & depth) of the twins, centre and ventral fins you were using, to check if my impressions that the Stavron fins are too big is just that, an impression?

Also, I remember reading a while ago in a thread which I cannot manage to find that there are two fin box standards (US and cannot remember the other) that are very similar but differ by a small amount in width, does anybody have the width of the two box types?

 


SimplePortal 2.3.7 © 2008-2024, SimplePortal