What is the difference between 2 fin and 4 fin fish?
2 is simple, less fins to foil, less to ding, costs less for less, can be snappier on turns
4 holds in better, can control amount of slide with amount of holding power, can be looser and yet still positive, can turn quick enough, costs more, more work…
If by 2 fin you mean keel type fins, then those tend to be stiffer but may also generate more speed.
Not necessarily, usually, and may or may not = maybe?
Don’t need to be keel, you could put a blade pointer on a tail width of 17" +, and not have interference.
Why is stiffer any good. Didn’t we already decide the correct amount of stiffness is all you need? Nothing should be stiff on a surfboard.
Speed is generated by the skill of the surfer. Just adding stiffer bigger, stiffer shorter, softer shorter or longer doesn’t equate more speed, just a different style of surfing needed.
If speed is your game, flatten the rocker, harden the rails, add any low drag fin that is big enough to handle YOUR power.
Well to be honest I was coming from a kneeboarding perspective which is/may be a bit different than a standup perspective re Fish (remember, however, Fish was originally a kneeboard design). Also, I was talking in general terms (e.g., ‘may be’, etc.). But I believe it quite safe as well as entirely reasonable to say that standard keel fins (9" x 5") are ‘stiffer’ because the board is not as loose (e.g., cutbacks require great effort to initiate) and faster because the traditional fin setting (kneeboard) was parallel, close to rail/tail. Turns are usually more drawn out. But thin about it for a moment. To simplify matters let’s compare 2 fins v. 4 fins with the exact same surface area. The 4 fin has a different flow pattern. The water has an outlet (between and through the fins). In fact, that is why the 4 fin set up was invented/introduced. To break up the fin outline. And to complicate matters even futher 4 fins can be set up in such vastly different ways that it is hard to make exact comparisons (e.g., larger front fins, smaller trailing,…opposite set up…fins close together…far apart…etc., etc., etc…take your pick)! Much less variability available with 2 keel fins. Set parallel (stiffer as board will track). Towed in slightly (easier to turn). Simply put 4 fins means at least twice the variabity re set up. Once again from a kneeboard perspective. Standup other factors come into play (back foot v. front foot surfer). Also outline a bit differnet on standup Fishes. Only way to truly understand/know/feel the difference would be to try different fin set up (2 keels v. quad) on the exact same board which would require mucho work as keel fins must invariably be glassed on (are there any removal keel fin set ups? None that I am aware of…anyone know of any?).