Aloha I have several small single fins in my quiver – 6’ eggs and 6’4" “shortboard” designs that have the fin box setup. I have been using True Ames Norm fins, 7" and 8" flex. These fins work great in point surf, or smaller beachbreak waves. However, I have found that as soon as the waves are overhead, or barreling, my boards seem to slide out when doing a bottom turn or cutback – it feels as if the fins are being overpowered. I believe I need a stiff fin for those overhead, hollow days. Any input on good fins for the above mentioned boards? Thanks for reading, Kit
try a 9" l-flex or perhaps some of the smaller(8"-9") greenough fins by true ames.
Hey Kit, Drop me an email We can discuss the boards you ride and how they perfrom in different conditions. Every board configuration has it’s limitations but maybe we can come up with a fin or two that will help you move up the performance curve. Mahalo, Rich
Flex fins do not work in powerful surf. Rather, if their flex is set up to work well in smaller waves, it will not work in bigger waves. And, even if you get a stiffer version, the rear of the board will fishtail when you try to go straight. It doesn’t work. The fin has to track well when going straight. You’d be better off in bigger surf with a stiff cutaway, which will still allow you some of the turning advantages of the flex fin, but will track well when going straight. http://www.blakestah.com/surf/
Check solosurfer.com for Horan keels and Mccoy gull wings.
Gotta call you on this one…A little deeper fin maybe and some adjustment fore or aft. I’ve ridden an awfull lot of big waves using a TUNED flex fin and have had nothing but positive results. A poorly designed fin is a completely different story. Mavericks, Waimea, Todos, Sunset might need stiffies too but we are talking a whole 'nother realm there.
Fins that can rotate, like a flex fin, have a problem that is unavoidable. The fin is centered with some force. This force smoothly increases as the fin moves side to side. As the fin moves side to side, it also moves the rider’s weight side to side. If the forces on the fin are high enough (which occurs with more speed), the system is pushed out of its stable range, and the rear will fishtail. The same occurs on a skateboard. It becomes less stable as your speed increases, and can wobble. Even very good skaters will sometimes fall into a speed wobble - better skaters get good at dampening it. It is possible good surfers could do that on a flex fin as well, but mostly they just don’t use them in high speed situations. At least one skateboard truck (exkate) was designed to eliminate this problem. This problem is common in self-correcting steering systems. Bicycles riders get speed shimmy. The problem was corrected in automotive steering systems a long time ago. It is still present in those little scooters kids ride around on. Another way to eliminate the problem is to just stiffen the system. This pushes the problem into a higher speed range, but hinders performance at lower speeds. The trick is solving the problem at all speeds, and still allowing the self-correcting steering at all speeds. For this reason, most surfers only use flex fins in slower surf. http://www.blakestah.com/surf/
Correctly tuned flex equipment, i.e. surfcraft, fins… ALL function better as size and power increase. The whole idea is to achieve balanced handling, increasing the operating range. BTW, tuned, flexible RIDERS function better as size and power increase, too.
Flex indicates a force-to-bending relationship. These relationships cannot be optimized at all forces. If it is optimized for small forces, it will be out of its league for larger forces. Cigarette boats are less maneuverable than Boston Whalers at 5 MPH in smooth water. But, take them up to high speeds on the open ocean, and it is a difference story, the cigarette boat can turn much better than the whaler. Same with flex fins. If it turns well at low speeds, it will be out of its league for larger speeds. And, if it turns well at high speeds, it will probably not turn much at all at low speeds. http://www.blakestah.com/surf/
If we were talking about the difference between 5 mph surfboards and 50 mph surfboards I might agree. We’re not. I think the performance envelope for the well-designed flex fins I use certainly encompasses 15 mph and 25 mph and .5g to 4g. I think that most folks would agree that Mr. Greenough has probably gone about as fast as anyone on a single finned surf vehicle and he used flex fins exclusively. I have been dragged behind a ski boat at 38 mph on several boards with flex fins and have never, ever experienced “speed wobble” (even after I let go). I would guess that the original poster’s problems were a miss-matched fin/rail/rocker combo that didn’t surface until he got in a critical situation.
ditto-never had a problem with flex fins in big surf-if there was a wobble, I would just change fin placement accordingly…
Ditto for me as well were not tryin to gang up here but it take time to know how to tune flex fins . I can see how younger surfers who have just ridden thrusters might just blow them off.Matt and I have 2o+ fins each and are still borrowing each others all the time for that magic combo.But to say they just dont work in bigger surf is a pretty broad statement.KP
Kit, Aside from changing position, one solution may be a deeper, slightly firmer fin, yet with less area. The function of a flex fin is optimized when it shares in a board’s ability to remain attached to a wave, through convex bottom and rail contours. An effective board and fin will work together to produce an effect greater than the sum of their individual effects. The larger, more powerful and faster a wave, the more critical balanced handling becomes. Synergy is everything in the best surfcraft and fin design.
Thanks Dale and all for the suggestions. I will experiment with what I have (i.e. changing position of the fin, though I have done this before), as well as trying other fins with a slightly stiffer flex component. Mahalo Kit