Just got the first test production run of the New Maui Ultra Fins Delta XT. Looks interesting and I can't wait to get it on the water to see how it goes. The surface area of the New Delta XT is about the same as the Original MUF Delta but they have move it from the front to the back. The Delta XT has less rake than the MUF Delta. The Delta XT has been designed to have more grip and get up and go than a MUF Delta and fingers crossed it will be lighting fast. Unfortunately the first test production run was only power box but that's good for me with my Twin Fin power box boards. Also only in sizes 18,20 and 22 the next production run should include 16, 24 and 26

That low depth twin fin setup may be the perfect combo for Pt Grey where the acres of hard packed sand usually mean if you misjudge the depth and touch when planning with a normal tip fin, you will have to walk a long way to get enough water to get going again. Large tip stops digging in. Twin shortens length.
Whilst in theory low aspects are not as efficient hydrodynamically from experience we have found flat water trumps everything (now there is a word that is getting a new meaning).

But, in theory, the twin fin setup will decrease efficiency even more? Any reports on performance?

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sailquik said..
But, in theory, the twin fin setup will decrease efficiency even more? Any reports on performance?

My experience with Twin fin any lack of efficiency is made up for in comfort and confidence in the fins not spinning out. Also you are using 2 smaller fins than one bigger one for a single fin board to get the same performance. I am a heavy guy and if I was to sail Budgie with a single delta fin I would need one to big to get into the flat water in the shallow spots. With a Twin fin I can get away with 18 deltas and am planning to try the new delta xt 16 when I get some. It is also hard to compare performance as all the Twin Fins I have had are freeride boards which are not going to be as fast as a Slalom board.

Legless, I imagine you can gybe harder too in comparison to a single fin Delta?

Yes. I have found any sort of Delta is a severe compromise but anything that can get you into really flat shallow water is great.

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Stretchy said..
Legless, I imagine you can gybe harder too in comparison to a single fin Delta?

With Delta twin fins you have more grip with one of the fins staying deeper in the water than the fin on a single fin board with a delta. This seems to be more apparent the wider the board you are using. The guys with wide single fin boards at budgie often find gybing an issue as the can't sail with a big enough fin to cope with a hard gybe as the fin looses its grip.

Did you get the board custom made with twin boxes? What brand?

When a board is drawn up for placement of the fins, a line is usually drawn from a point on the nose as in the case of thrusters and twin fins. I was wondering whether the angle of attack on both fins would be the same (for speed sailing), or whether, whilst one fin was tracking true the other was actually inducing drag by being slightly off kilter? Or does it have negligible effect on tracking, being purposefully built for waves?

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sailquik said..
Did you get the board custom made with twin boxes? What brand?

Cutouts would indicate twin arrangement was an after thought. If board originally designed for twins then a dovetail would keep trailing edge of fins further from air ventilation source.

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sailquik said..
Did you get the board custom made with twin boxes? What brand?

F2 Vegas Twin 2017

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yoyo said..

sailquik said..
Did you get the board custom made with twin boxes? What brand?

Cutouts would indicate twin arrangement was an after thought. If board originally designed for twins then a dovetail would keep trailing edge of fins further from air ventilation source.

F2 make a single fin version of the same board. I also have had Hilfy Twin fin boards with out cuts outs. I have not noticed any negative effects from the cut outs.

Nice looking boards legless. Can you tell me if the fin boxes are perpendicular or slightly canted towards the nose?

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pepe47 said..
Nice looking boards legless. Can you tell me if the fin boxes are perpendicular or slightly canted towards the nose?

The fin boxes are straight and not canted towards the nose.

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legless said..

yoyo said..
Cutouts would indicate twin arrangement was an after thought. If board originally designed for twins then a dovetail would keep trailing edge of fins further from air ventilation source.

............ I have not noticed any negative effects from the cut outs.

Interesting to hear. My initial impression was to close to air source but practice is the true test. If it works, it works.
Like the look of the other two.

In the photo, rake looks to be approx 45 degrees, which previously has not been enough to cope with the weed here. So I am wondering, is our weed unusually thick, or are the fins aimed at the shallow sandy runs, rather than weedy runs?

Would a single assy fin work better being off center in the board?

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fangman said..
In the photo, rake looks to be approx 45 degrees, which previously has not been enough to cope with the weed here. So I am wondering, is our weed unusually thick, or are the fins aimed at the shallow sandy runs, rather than weedy runs?

It is around 50 degrees. I will be testing them in the shallow weedy spots at budgie (when the water drops at budgie). I do not think it will have a problem in the thick weed at budgie.

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choco said..
Would a single assy fin work better being off center in the board?

I have twin assy fins I have been trying out in the boards. I have not decided yet if it is better or not. First I have been trying to work out which way round the fins work best.

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choco said..
Would a single assy fin work better being off center in the board?

You've opened a can of worms here Choco. Of course not. Sailing on starboard is the most asymetrical activity you could imagine. The only reason the gear you're on is symetrical is for a giant compromise so that you can come back on port. I'd guess an assy fin is better on the leeward rail. And that it should be matched to an assy board with a straighter leeward rail and a windward mast track. Too many variables. Don' t go there. We should have banned assy fins when we had the chance. They were the thin end of the wedge.

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legless said..

fangman said..
In the photo, rake looks to be approx 45 degrees, which previously has not been enough to cope with the weed here. So I am wondering, is our weed unusually thick, or are the fins aimed at the shallow sandy runs, rather than weedy runs?

It is around 50 degrees. I will be testing them in the shallow weedy spots at budgie (when the water drops at budgie). I do not think it will have a problem in the thick weed at budgie.

Excellent stuff. I look forward to hearing how they go

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Ian K said..
Don' t go there. We should have banned assy fins when we had the chance. They were the thin end of the wedge.

Which wedge is that Ian?

Lockwood, Tribal and TimeMachine (Wright) Assy's go upwind on the 'wrong' side quite well within a limited speed range.

A good Assy is a joy to ride down a speed course.

The MXR Assy's designed for the Luderitz canal where strictly one way, and a trailer ride back! I couldn't even go upwind on the glass at Lake George on them!

Pepe: Toe in on surfboards is specific to wave riding, the water flow up the face and manoeuvrability. Toe-in creates quite a bit of drag in a straight line and would be disastrous on a speed or slalom board. Tri-fin wave boards I have had were a lot faster and easier to plane up with a single fin only. Not as nice on a wave though.

I tried one of these deltas yesterday at Budgy. I have always been underfinned with a 20cm original delta on my 75cm wide freemove with the 7.8m. I demoed a 22cm one and loved it! Budgy is still high but it has dropped a fairbit.
I spun out a few times but that was in overpowering gusts I wasn't ready for. I loved the fact that for once I could actually trust the fin and press against it and felt really comfortable sailing it.
I must have been using a fair bit of pressure as when I came in and tried to walk my ankle ( still recovering with torn scar tissue) gave me grief and was very painful..That generally only happens after being out in chop and pressing against decent fins .
No hassles with the weed although it isn't as shallow as usual but if they are 50 degrees I can't see them having any issues.
Bought it.. I don't often use the big board at Budgy as it's really slow but I am looking forward to just having some fun lightwind sessions now I have a decent fin!

Had my first run on the Delta XT 20 and then the 18. in a choppy gusty 16-24 knot at canton. I was very impressed with the fins. Loads of grip the fins did not let go. Them seemed to go up wind better to. if I had been using my Delta 19 or Delta Speed 18's in those conditions they would have been slipping out. The water is not very shallow at the moment but there was thick clumps of floating weed I hit a few and the fins went through them with only a mild tug. Can't wait to try the fins in flat water when the water drops at Budgie. I did notice the fins whistled when powered up.

If there are any SA sailors with this product, then I would like to have a few runs on your fin before deciding to order one.

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jn1 said..
If there are any SA sailors with this product, then I would like to have a few runs on your fin before deciding to order one.

Only a few people in NSW have them.

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sailquik said..

Ian K said..
Don' t go there. We should have banned assy fins when we had the chance. They were the thin end of the wedge.

Which wedge is that Ian?

Should ban elliptical fins too - they perform much better than the football fins.... which is un-Australian.

Legless, what date are you expecting the XT to come out in tuttle. Looking for a 22cm.

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Dean 424 said..
Legless, what date are you expecting the XT to come out in tuttle. Looking for a 22cm.

Fingers crossed some time this month.

Ok thanks

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Dean 424 said..
Legless, what date are you expecting the XT to come out in tuttle. Looking for a 22cm.

The new MUF Delta XT tuttle box sizes 16 to 26 are in Australia