Fins - which does what?

[greypump]

Excuse the newbie questions but could someone tell me the characteristics of different fin set ups and the benefits of each?

Single fin (what does a larger one do compared to a smaller one - speed/stability?)
Quad,
three fins
two side fins etc

Many thanks

[Kabazz]

Longer fins result in longer drawn out turns
Shorts fins result is sharper 'looser' turns

[greypump]

Thanks Kabazz. Why have four or three or just one?

[parrysurf]

longer ones hold on steeper/ bigger waves..

Twin fins are snappy and loose....mostly for playful surf
thruster....arguably the best combo of drive and responsiveness
Quad......like a twin but more drive, still loose


I think someone should make a 21 fin board....market the piss out of it and people will buy it

[RJD]

Have a look at the bottom of a typical longboard tri fin setup..

Big center fin = stability and hold in the wave.

Side biters - there angled this increases straight line drag & creates instability BUT gives latteral thrust when turning.

i.e. the back of the boardmoves horizontaly WRT to the front.

With just the single fin you carve a turn as an arc, with the thrusters you get a shove sideways kinda like a handbrake turn.

[greypump]

I've got the big centre fin and two side fins - as a beginner is the three fin set up easier than the single fin? Single fin sounds more natural.

[RJD]

Probably, on a longboard, singlefin will be more stable and more cruisy turns for you.

Though if you remove the sides your likely going to need a larger center.

[greypump]

The centre fin is 8 inches deep - if I took the side fins off would I need a deeper fin? It's a 9ft 2 inch longboard.

[RJD]

Try, see how it goes!

[LeeM]

I have a similar board & setup on my 9'2" board. With the 2 +1 you get faster turns, but more drag. Surfing 2'-3' summer slop, I don't need drag. Without the side bites, I get less drag but less hold in turns, slidey I think is the description. I replaced my 7.5" with a single 9" Rainbow Rake and it turns and paddles better.

[parrysurf]

The centre fin is 8 inches deep - if I took the side fins off would I need a deeper fin? It's a 9ft 2 inch longboard.

I run a single 7.5 cut away on my 10'0 magic
my 10'6 single I am running a 9

Have to try...each surfer has different likes...I run small singles...loose and fun.....I will switch to a smaller board made for large waves if it is like that, so I don't have much need for big fins....plus I have charged DOH heaving beach break with that 7.5 and she held fine!