One of the challenges in purchasing a race fin, is finding the right one for your needs. As you can imagine, there are a plethora of choices out there. There are a multitude of factors that will determine which fin or fins make the most sense for your particular application.
Some Key Variables:
- Board Length
- Water and Wind Conditions you typically paddle in
- Your ability level related to stroke technique and balance
- The Template of your board, i.e. amount of nose and tail rocker, and nose design (does it cut through water or sit on top?)
- Fin box location
- Is your board stable or tippy?
Aside from these factors listed above, there are other factors people use in choosing a fin, such as color, materials, weight of the fin, etc. Most of these last few have more to do with aesthetics than they do performance, but still may factor in to your decision.
As for the items in the list, I will take this space and try and articulate how each of these play into which fin/s you should choose.
Board Length - One thing that I have learned over the last few years in doing R&D on fins and boards, is that the common sense answer that comes to mind may not always be true. As an example, many people would assume the longer or bigger the board, the bigger the fin needs to be. I have found that in most cases, the opposite is true. I use a Gladiator Elite Fin (9″ in depth) in my 12’6 boards (Bark Competitors) – smallest race board, biggest fin. The reason for this is simple. It works better. I tend to try and optimize around 10-12 strokes per side on my race boards in light to moderate conditions. When using a smaller fin with this board, I can’t get to those numbers.
On my 14′ race board, I use a Gladiator Pro Model Fin. This fin is considerably smaller than the Elite. The reason I use this fin on this board is I can get to my 10 or so strokes per side with that fin (which is 7.25″ in depth) just fine. If I use the Hybrid fin, I can get north of 12 strokes per side. Sounds good on the surface, but I like to switch sides at around 10 or so strokes, as fatigue starts to factor in there. If I am going to switch sides at 10-11 strokes, then anything the fin provides above that, is left on the table. That doesn’t sound like a bad thing, until you realize a bigger fin results in more drag. The more drag, the slower you and your board go. The challenge is not to freak out and go the opposite direction and get a fin that is too small. If you do that, your board will yaw all over the place, which results in covering more distance than you need to, and it results in having to switch sides too often, which means you lose strokes along the way. Balance is key, and 1 size does not fit all.
I also ride an unlimited board (MHL 17’6 Custom), which is the board I try and race on most of time. I am a huge supporter of the Unlimited class, as a lot of the innovation occurs there first, and trickles down into the smaller sized boards. On my Unlimited Board, I actually ride an even smaller fin. It is called the Gladiator Ventral Rear fin (6.75″ deep). It was designed to be a part of a 2 fin system, where there is a front fin. I ride this fin by itself though, and can easily get 12+ strokes per side in flat water conditions. The reason is, this board has less tail rocker than the others, so the fin is automatically sitting a little deeper in the water. Plus, the added water line, and needle like sharp nose, common to UL class board, allow this board to track really well without a lot of extra help from the fin.
Water and Wind Conditions - I think this part is possibly the biggest factor, for me at least, in choosing a fin. If you paddle on clam, flat conditions, you can get away with a smaller fin. If you find you are in rough water, a bigger fin is a better choice, as it provides better tracking and more stability. Where it gets tricky is the wind piece of the equation. If you are dealing with a tail wind or head wind, you will some flexibility with what fin you go with. the challenge is picking the right fin for side wind, and/or diagonal side/head wind. For the record, I hate paddling in those conditions. In this area, there isn’t a perfect answer for everyone. Personal preference, as well as board design plays into what you should do fin wise for these conditions. A bigger deeper fin will help you you track better in side or diagonal winds, but the challenge is, it will push your bow around, and when it does, you have to correct it and swing it back into the wind, to keep going straight. The bigger fin will actually work against you in this situation, as it was designed to track straight ahead. When I say board design can play into what you do here, I mean bow design primarily. Boards with big thick bows, tend to get pushed around more, than boards with a slimmer profile bow. For these boards, I like to go a little smaller on the rear fin, and step a little more forward than normal on the nose, to try and burry it in the water more. For boards that sit more in the water, and/or have a slimmer profile nose, I like a moderate to large sized fin. If the nose isn’t getting pushed around as much, give me the better tracking fin. Again, personal preference.
Paddlers Abilities – This is another area where it tends to be a bit subjective. What is the criteria for whether someone is beginner, intermediate, advanced, or Elite/Pro paddler? Beginner is fairly straight forward, but it starts to get cloudy after that. What it comes down to for me are these two things: How good is your balance? How good is your stroke technique? The reason balance is important, is because I tend to recommend bigger fins (such as our Gladiator Elite) for people that have weak to moderate balance. That fin does a really nice job of stabilizing the board. If you have really good balance, I recommend a smaller fin, in order to reduce drag. The same thing goes for stroke technique. People who have really strong technique, can keep their board going straighter, without as much help from the fin. People that are still learning or adapting their technique, will tend to appreciate more help from the fin, until their skill level improves.
Template or design of the board - I have already covered some of these factors in the the sections above. In addition to those factors, I will add that some boards have a lot of rocker, and some are fairly straight. A good rule of thumb is, boards with more rocker, need more fin. They will often have less of the nose in the water helping tracking, and a lot of tail rocker will also result in less fin in the water helping to keep you on track. Nose shape is also a factor to consider. I have found that boards with sharper/knifier shaped noses tend to track better, than boards with blunter noses, especially if that nose is buried deeper into the water, helping to displace the water as opposed to planing over it. Each board is a little different, so take this as a general statement, and not a finite answer. Your mileage may vary.
Fin Box Location/s - This one is pretty simple. The farther forward your fin box is, the deeper you need your fin to go to compensate. I will give you an example. If you put a Gladiator Pro Model fin on an Infinity Whiplash Board, it works great. Put that same fin in a M&M board, and you will find it yaws a lot. The reason is fin box location. The fin box on the M&M is really far forward, compared to most boards. For the M&M board, the Ninja fin is a better choice, as that fin is 10″ deep, and compensates for the forward style box location. There are exceptions to this, Beau Whitehead of Washington, went from a Ninja to a Pro Model (on his M&M), and loved it because it was faster. That said, he does have to deal with more yaw now than he did with the Ninja. For someone of Beau’s ability, this may be a fine choice. For most paddlers though, the advice above is better.
Stability of your Board - I have mostly covered this already, but a bigger fin will add more lateral stability to a board. If your board is tippy, get a bigger fin. If your board is stable, reduce drag and go with smaller fin. One of our team riders at SUP Gladiator, Chance Uptmore, is living proof of what I am saying here. He and I traveled to Carolina for the Cup 2 years ago. We rented him a board, which was way to small for him. He was sitting around 275LBS and 6’6 at the time. The board was both too narrow and not enough volume for someone of his size. As he paddled around on it the day before the race, he was extremely nervous. The board was way too tippy for him. Because of his size, he relies on very long powerful strokes. Having a tippy board, would mean having to alter that style, so as not to constantly fall off the board. On race day, I replaced the stock fin with a Gladiator Elite fin. It made all the difference in the world. He finished first place overall, out of 125 riders in his race. He was shocked at how much better the board worked for him, with something as simple as a fin change. He was skeptical when I told him I could fix the stability with the right fin. He isn’t any more.
Other factors - A lot of people get hung up on the materials or weight of a race fin. In truth, we are only talking about a couple of ounces difference at most. At SUP Gladiator, we are playing around with alternate materials to add to our line up of fiberglass fins. These molded fins do solve a problem for me, in that they are made in China and I can get them cheaper and in much higher quantities than our hand made fiberglass (Made in the USA) fins. As for the weight differences, once they are on the board, I can’t feel any difference. In other words, don’t believe the hype. If you like the look of Honeycomb, buy the fin because of that, not because it will make you go faster. In some cases, it will have an adverse affect, in that lighter weight fins, often tend to flex more, which will hurt tracking and lateral stability. In all fairness though, even that I have a hard time noticing if you get a good quality, stiff fin.
I realize this was a very long post, so thank you for reading it through to this point. Some of the things mentioned here are just plain physics, and true in all cases, where others are somewhat subjective, and vary from case to case. If after all of this, you still have questions on what fin to select, feel free to email me at firstname.lastname@example.org and I will be happy to help you further.