Wow, that seems like a ton of fin. I also lean towards underfinning everything. What effect are noticing from running that bigger 4a?Based on some JC Neslon video's I have been installing bigger fins in my boards and so far it seems to work out.
Slowly starting to come to the realisation I have been underfinning my boards for decades.
Just got a new 9,75 Greenough 4A for my 8' Outlier
Of course fin size is related to surfer size and the power in their style of surfing, not just board design.I have yet to surf it, but will post an update as soon as I do.
I have the 10,5 parallax fin (the biggest) in my 9'3 Parallax board (the smallest). Perfect fit. CJ surfs the 10,5 in the 9'6 board.
There is a video where he installs a 9,5 fin in the 7'6 Outlier.
I am starting to wonder if fin sizing should be related to surfer size and surfing purposes and not neccesarily just the board dimensions. Like when I step back to initiate a turn its not really relevant if the nose of the board (sticking out of the water anyway) is 7, 8 or 9 feet away.
All a bit of a grey area as everything is related obviously but I think that for my size and weight and the amount of pressure I put on my back foot I should surf larger fins. If I want to change specific elements of the performance I should search out different fin templates.
For singles I have been getting good results with somewhat narrow-tipped and upright templates. Fins that take a lot of surface all the way to the tip tend to be very "holdy"
I dont really know. Just been surfing well on larger fins