Quad fin advice

lawnmower · Since 14 Dec 2007 153 Posts Stoked

Got an Airush 54 with the swept 20, 17 swept tri setup. I found it very skittish and hard to jibe. I ordered a set of mini Tuttle to FCS converters, and am looking for advise on FCS quad sets that would work with that board. My usual ride is a Slingshot Dialer which is aircraft carrier easy. Would like better up wind performance but not monster 20 CM fins.

ShiverMeTimbers · Since 26 Feb 2013 381 Posts Gig Harbor Obsessed

If its skittish, try a larger center fin. it could also be foot placement on the jibes. also, that wide tail is gonna skate when the rails are out of the water.

eabmoto · Since 10 May 2012 107 Posts seattle Stoked

That board is a light wind/up wind machine only because of the big fins. I've tried one. They take some getting used to for sure. I had to put my back foot in front of the foot strap to feel right.

AndyD · Since 17 Mar 2008 53 Posts Bend, OR

I'd encourage you to give it some time and learn the nuances of the board. I've had my V3 since July of 2012 and I still love riding it. Its by far the easiest board I have when it comes to moving my feet around (2013 Naish Skater, 2013 Cabrinha Trigger, 2015 NorthPacific Waterbug Venturi and 2014 Lift foil). Its not the easiest board to learn but its a great board when you have light wind or strong tides/current like we can experience in Puget Sound. When i'm carving turns I have both feet in the straps (I run 2 not 3) and often when I'm riding up wind, I have my back foot just in front of the rear strap.

Matt V · Tue Aug 18, 15 9:31 am

Any one have any idea of the actual physics of "back foot in front of the back strap for upwind".

I have done it (my biggest board was a converted 6'-0" Slingshot "Coupe" converted to Quad fin) but I do not seem to get any benefit from moving my back foot up. I also do not use any tri-finned boards so this pertains to quads only. And I came from a background of sailing bigger windsurf gear and know how to side load a large finned winsurf board "midwest style" and hiked out, as opposed to straight over the windsurfboard like high wind "Gorge Style".

My take on it is that by moving your back forward, you are increasing the leverage the fins have over you and decreasing the leverage (decreasing the potential force) you can apply to the fins. The only benefit that I can see is that you lessen your chance for spinning out the fins via over pressuring (sideloading) or cavitation when sending air under the board in chop. So by my theory, this is something useful for beginners and those who do not want to take the time to get a feel for the fins. Not that you should not do it, but I really feel that for me, it is not something I have ever gained an upwind benefit from.

lawnmower · Since 14 Dec 2007 153 Posts Stoked

So AndyD, switching to a standard quad setup won't help my ineptitude?

ShiverMeTimbers · Since 26 Feb 2013 381 Posts Gig Harbor Obsessed

switching to a quad won't make the board less skittish in gybes. If you don't have the rail sunk into the water, like when in mid-gybe, a wide tail is more prone to skating around instead of holding a line.

The general rule, coming from a surfing background, is wider tail = bigger fins. A quad may give you more fin to push against when the rails are in the water, but won't do squat for when the board is flat on the water (mid-gybe), which was your initial complaint.

eabmoto · Since 10 May 2012 107 Posts seattle Stoked

I put my back foot forward on the sector because it just felt better balanced. I don't think I was getting up wind better. I usually don't ride with straps. I tend to move my back foot a lot.

AndyD · Since 17 Mar 2008 53 Posts Bend, OR

Since I don't know you or your skills or how you like to ride your boards its hard for me to say. Just sharing my experience with that particular board. But I don't think changing to 4 smaller fins is going to get you the stability you're looking for.

bwd · Since 04 Aug 2007 385 Posts Obsessed

With quad setup having big front fins, those are the fins you are loading. The back fin is there for tracking and to work when the front fin is not loaded right from ventilation, chop, momentary aoa changes etc.
With a gnarly race set up having low to no toe in, maybe all find could work efficiently at once. Or spin out at once... That can present a type of gnar I'm not into, but it's another story from surfboard or sector, slayer.
So you are actually loading the front fine better, and feeling them better to keep control, with back foot closer to them. If the windsurfing boards had been finned that way instead of big singles, you would have wanted to move th back foot up on them, too.
And another tangent: you can learn to ride your thruster better, by taking the center fin out and riding it as a twin for a bit, then reinstate it and learn more about what it's doing for ya

lawnmower · Since 14 Dec 2007 153 Posts Stoked

When I tried putting the back foot in the strap the board felt really goofy so the back foot is now forward of the back strap. I lent the board to a gal who won KB4C with it. Her comment was to use the back foot to push down on the leeward rail to get the board to ride flat. I realize that general lawn mowing is different than jibing. The sector outline is almost the same as my Dialer with the exception of the Dialers swallow tail. Since the Dialer jibes like a dream it's either the fins or the tail. I was hoping fins would be the answer since I don't want to take a hacksaw to the Sector.

eabmoto · Since 10 May 2012 107 Posts seattle Stoked

The big fins want to go straight. I'll take time to feel comfortable turning it. If you put smaller fins on it, it will feel similar to your other board but then why have it. It's purpose is to get you out in lighter wind and aim higher up wind. The big fins are what do that.

tonyb · Wed Aug 19, 15 1:58 pm

Try leaving the big fins up front and putting regular surf fins in the back using the Tuttle to FCS adapters. You'll get about 90% or better of the upwind ability but the small fins in back will make the jibes much easier and it improves the downwind handling. That's the set up we use in KB4C and it's worked really well. Big fins in the back help the board to track straighter and get some lift off of the front fins, that may be what's making your jibe harder to come around.

Tony