McCoy Four Fins? NOT!

All things being equal, more surface area means more drive.

Lack of centre fin drag helps too, no?

Yep, through a turn, water runs across the rear fin at a greater angle which creates drag - but also stabilises the board.

Ha well there ya go. It was a long time ago, and it does seem logical re the drag. But in that sense isn't 4 find more surface area than 3 fins and therefore more drag?

Maybe it's the stability that counterintuitively gives the driveability?

I mean I love a good cutty but remember that the quaddie was fast and easy, but a thruster just drives all the way through. I guess it depends on how fast you are going at the time, amongst other things.

Yeah, with no rider input, more fin in the water creates more drag, however multi-fin boards are pumped for speed, with the pumping motion pushing fin face against water - more fin face = more drive.

There's a lot to discuss here, and the fundamentals aren't that complex when explained in isolation. Might do an article on it soon.

Cheers Stu. An article would be great. The nuances and science of design is way above my pay grade and any effort to de-mystify would be welcome.

‘however multi-fin boards are pumped for speed, with the pumping motion pushing fin face against water - more fin face = more drive.’

Oh oh... of course that obviously raises the subject of the effectiveness of the ‘pump’. Think surfing a wave pool wave generated by a pissy little fucker. Sure, you can tweak all the little fucker’s variables to up the anti so to speak, but it would be like flushing the dunny, and jumping in... (think dribbleton and mid coast aspirations).

We know that the reality is, that the pump required to generate anything close to prompting the likes of goofball drawing the mighty storm from the scabbard is a beast of a thing.

However... two ‘epic’ subjects that are enough to drive swillnut executives into a gnashing, quivering, foaming, in fact even deafening, red mist (again) style meltdown are...

‘DON’T EVER FUCKING MENTION STINKIN’ GLUTES OR FUCKING HAIR EVER AGAIN!!!!!!’

In a nutshell.

The moral of the story???!!

If you get a typical east coast, ne seabreeze grovel, or newies nobbies debacle, please don't come back to the shed slathering, and blathering, and foaming and squwarkin' and jibberin', and frothing, about 'power packed slabs' an' 'pits', an' 'bombs' an' 'wedges' an' 'foamballs' an' 'slammin'', an' 'jammin'' an' 'carvin'' an' shite...

Please don't... not again... please stop...

No my little swillnuts, deep down, we all know the truth about those 'ne seabreeze grovels, or newies nobbies debacles', we all see through the 'slathering, and blathering, and foaming and squwarkin' and jibberin', and frothing, about 'power packed slabs' an' 'pits', an' 'bombs' an' 'wedges' an' 'foamballs' an' 'slammin'', an' 'jammin'' an' 'carvin'' an' shite...' don't we...

Think... 'haiya lifty'... again...

Carry on swillnuttin'... little swillnuts...

If there really is that many guys going to the effort of changing fin set ups on his boards, it's obviously because one guy did it and liked it and words got around and others are trying it, otherwise how many people would really go to the effort of getting a three plug board changed too a 5 plug board?

It's all subjective anyway, surfing is just as much about how it feels for the surfer, if a guy changes a board from a thruster to a quad, and he prefers it as a quad, then it works for him/her.

Got me thinking about the old 4 vs 3 fin setup and found the below info (which seems logical):

"One point, on which Kelly Slater, Jeff Clark and most other pros and shapers who have experimented with four-fins agree upon is that quads are faster than thrusters. This is because they generate more drive through a turn and are able to hold a higher line (whether being pumped or not) on steep wave faces. This performance advantage quads have is due to their greater-fin surface area, which results in quads slipping sideways through the water less easily than thrusters (they "hold" more), resulting in more of the riders energy being redirected into forward momentum. In other words; quads are simply more efficient and so better than thrusters when it comes to holding a high line and doing rail turns.

This means that quads perform well in particular conditions where a surfer needs as much speed as possible, such as in big waves, deep barrel sections and tiny, "gutless" beach breaks.

The Quad's efficiency in turns also makes them particularly suited to power-surfers who want to hack-n-hold their way through full-rail turns, cutbacks and lip-smashes like Taylor Knox. However they're not so good in conditions which favour a new school approach. This is because their extra-speed and fin-surface area makes it harder to perform release-and-recover manoeuvres such as tail-slides, air reverses and any other moves which require the board to slide side-ways or backwards. In comparison, the thruster's relatively inefficient fin-set-up makes it tail much freer when the weight is taken off it, allowing riders to perform new-school moves with greater ease."

I've got a Wayne Lynch thruster I could turn into a quaddie. That'd be new...

Yep, all that WOTL, and the reason quads want to run laterally is because the extra fin area tries to force the board 90 degrees to the way the water is moving, which, in the case of a breaking wave, is up the face.

Think of a rudderless boat turning beam on at sea.

All finned board will do it, but the effect is pronounced on quads due to fin area.

"However they're not so good in conditions which favour a new school approach. This is because their extra-speed and fin-surface area makes it harder to perform release-and-recover manoeuvres such as tail-slides, air reverses and any other moves which require the board to slide side-ways or backwards. In comparison, the thruster's relatively inefficient fin-set-up makes it tail much freer when the weight is taken off it, allowing riders to perform new-school moves with greater ease."

Hmm im surprised to read the tail slide bit, i find it much easier to slide the tail on a quad both forehand and backhand my tail rarely slides out with thrusters but with the quad set ups i run which are just average size fins push them hard and they slide, sometimes good if you pull of something amazing, but other times you just skip and slide and loose control.

Same with old school sliding 360s heaps easier on a quad.

I thought pros preferred thrusters as they just go better top to bottom, but I am surprised more pros don't ride quads.

I personally have a love hate thing with quads.

BTW. I've tried nubsters in quads and in theory they should work, but in my experience they suck, just feels like a quad dragging something, but dont have the benefit of a thruster, instead of the best of both worlds, to me it feel like the worst of both worlds.

I probably should have posted my McCoy post on a new thread, didn’t really want to enter the quad vs thrust debate. It’s a board that feels great to surf.

For the record every board I’ve ever had with 5 plugs ends up a quad, or twin or quad plus nubster (they really make a difference when finishing round house cutbacks on a quad).

I’m sure the McCoy I have would fly as a quad, but I’ve been surfing it mostly in dribble and it flies down the line and surfs vertically very well.

Thought I'd chime into this old thread. I have a McCoy nugget (XF 6'1") with the mini-gullwing fins and an Astron Zot 6'6" unmodified I've had for maybe 5 years.
The Zot has been a real love/hate thing for me. At first I hated all that volume but now a few years later (and nearly 58 years old) i am really appreciating the early take-offs and easy paddling. I think that's good at any age though but it was a difficult transition from shorter and much lower volume boards.

What I came here to say that was I'd stopped riding the Zot because it was just too unpredictable. Sometimes it'd go ok but then next wave I'd struggle to turn,, or get drive, or it would want to go a direction all on its own. Weird. Sometimes the speed would come out of nowhere and I'd fall off the back. Was I not standing in the right spot? Was the fin in the wrong position? Was I just bloody hopeless? Now and then something clicked and I'd have great moments but they were too far between. I also had other boards and would ride then of the XF nugget which seemed like a great board for me (even that, after forcing myself to get that back foot right back I recall the first time Ii got the weight where it needs it and WOAH !)

One day recently I decided to try a different fin so I replaced the gullwing with a standard looking 8.5" captain fin co - greenough. First time out I felt the difference immediately. More drive, better behaved with a wider range of acceptance of foot position and wave type. Was it just a fluke?. .... next time out, different waves (onshore and bit sloppy), again I nailed the conditions. Next time out, fast sucky waves demanding a take off at an extreme angle along the face to make it and plenty of drive.....again just killed it.

Today I thought I'd revisit the gullwing and after 4 or 5 waves I just paddled to shore. Man I cannot make that thing work like people say it does. I felt like I was stalling on the face, lacking drive and speed and felt a general lack of connectedness with the board. (mind you i have felt it drive well before but mainly on hollow waves. maybe its a hollow wave fin and not a general purpose fin...I don't know)

I'm a pretty average surfer but with the standard dolphin style fin I felt like I was really excelling. Even once got a comment from another surfer how he couldn't believe I made such a steep drop so deep on one wave and then made it along the face. I felt I could not do wrong with that fin.

So the moral is, if you're struggling on a McCoy single that has a gullwing fin, I recommend you try a different fin before you start adding more fins. For me and my surfing style the dolphin fin transformed the Zot from the unused rack to my favorite board. Maybe I'm just not good enough to make the gullwing work so I don't t want to criticise the design at all but feel its worth telling my experience . It was the first time I realised just how much difference to the whole board that the fin can make.

to clarify my previous message....... the fin changes were on the ZOT from gullwing to dolphin.

Yes,Jeffn I agree.

Ive experimented lots with all the fin set ups, over the last 25 years.

A standard fin with a longer base is a better all round option than the GF.

I have 6/4 and 7/1 Zots,great boards that I use as a change.Also the 6/4 doubles as a gun kneeboard.

The Zot with GF does best in clean grunt waves but dont all boards?

How are the mini gulls as a thruster?Ive watched GMs fin thing on YT, best thing since sliced bread?

Btw, its 10 years this year of riding Quad McCoys.Still the board I prefer in lots of conditions.

quadzilla, the nugget thruster with mini-gullwings goes well. I've never ridden that board with the normal fins though. They look small on the board but they impart plenty of drive and can turn real easy. I've never had my legrope catch on them like some people have been worried about. I can't imagine they will be any better than a standard fin though otherwise every board would have them. I think nature does it best, and fish fins are characteristically swept back. The only fish fin that looks like the gullwing is a humpback whale fin and they move pretty slow. So I reckon that most non-dolphin style fins are more of an exercise in artistic license than engineering.

I used to gravitate to things with esoteric appeal. I liked to avoid mediocrity. That's one of the reasons I bought the Zot in the first place........ but more and more lately I'm starting to give in to the idea that there is a reason that common things are popular. They work.

Anyhow the Zot and the dolphin fin has got me on a single-fin bender at the moment. The surf journey continues....no two days, or waves, are the same.......onward we go.......