Thanks Terry McTool - I changed out the duct tape for a small zip tie to make sure it didn't pop open. The chicken loop actually moves reasonably smoothly across the bar BUT because the bar is pinched in at the ends it abruptly slots in (at either side) so you have to help it out. Not sure what to do about that yet, might be back to rope. Otherwise happy, my harness doesn't move around/give me chaffing on the beer handles and I save $$$ on one of those fancy harnesses.

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JacobMatan said..
Hi Dimi Sup how have you made the custom chicken loop for the naish bar, what did you use for the metal part that fits into the QR and what is that your using to hold the safety line next to the bar?

That is pretty much what I am after

The original Naish metal buckle was too big for my taste (and my initial sliding ring) and that is why I self made a new one, since I was afraid that the CL could jam. I bought a 3mm stainless steel rod, bended it in the desired form and a friend welded it for me. You can use also the original buckle but you will need bigger ring and your 'CL' will be slightly longer (which in fact is not a problem at all).

For the CL I spliced a 4mm Dyneema rope (both ends with locked Brummel eye, double stitched for safety).

To keep the safety line in place I use a Ronstan Split Ring 5/8 Diam. - (RF686) and my current sliding ring is a Ronstan 1" ring (RF123).

Before I ended up with this configuration one year ago I played for several months a lot with different designs and found that this setup (Dynabar with rope, sliding ring, Naish QR+self made naked CL) is simple, reliable and works best for me.

For the QR I think that it is best to use an existing, tested, proven, kite-oriented QR and I do not find any reason to play with some marine or climbing oriented shackles. For me the best is the Naish QR since it is very reliable, compact and super light.

The primary function of the PU tubing of the CL is to keep it in open O-form for easy hooking and unhooking (especially in the water) and together with the Donkey Dick to keep the CL in place when there is no tension in the lines. This open O-form is not needed at all if you attach your CL to a ring. The only reason to keep the original CL with PU tubing would be compatibility with a hook harness but besides that you gain only negatives from the tubing:
1. Possibility the tubing to crack and damage/cut the rope inside or jam during release or delay the release. When the CL is used with hook the load is divided in two points and the bending is ~90°. When attached to a ring the load is in one point in the middle of the CL (even with two rings) and the bend is ~180° - too much stress for the tubing and it wears much quicker.
2. The CL is always full of sand and salt.
3. The CL is usually too long which is not needed when attached to a ring.
So I prefer the naked CL - releases faster, smoother and more reliable, could be super short and you can easily clean it from sand and salt after every session.

Ring or pulley? I played with pulleys and did not like the result because the pulley moves to much, to fast which I do not like and the sand can jam it. Ring with thicker rod diameter (minimises the rope wear) is the best solution - super simple and 100% reliable.

Rope or belt, slider, etc? All other solutions (including rope with protective PU tubing) work either too fast, too slow, create erratic movements or are not reliable enough. The rope works best, it is most reliable (spliced Dyneema) and you can 'control' the sliding. The length of the rope is very important but not because of the 'infinite' forces which are created. With short rope you have very wide bending angle and the ring moves too fast, too much with erratic movements which is bad for the kite control. If the rope is too long the ring slides too little, too slow and also you sacrifice your depower reach. So everybody should experiment with rope length and find what best suits him. For me a bending angle ~90° works best.

As spreader bar you can use almost any bar but for me the latest Dynabar v8 is the best since it is super robust and reliable and it is flat - fits very well and you can lay on your surfboard without damaging it. The only drawback is the weight - it is a little bit too heavy (and too expensive) but I can live with that.

I hope you find this info useful.

Dam, can't edit on this forum.
Please change 30 deg to 150 deg.......

To elaborate a bit, with a 150 deg angle and 100kg pull on the chicken loop, there will be around 390kg pull on the rope/sling.
So do that magical 3G stunt and all of a sudden you have exceeded 900kg of the sling.
That can be lessened substantially by tying off on either side of the spreader bar instead of creating a triangle of rope.
Doing so would bring those figure down to 190kg and 570kg respectively.

I like the idea of your naked setup.
Do you think that my flat 12mm sling will have too much friction on the fat ring I have used?

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Absolutbeginer said..
I like the idea of your naked setup.
Do you think that my flat 12mm sling will have too much friction on the fat ring I have used?

I can not tell only from your picture. Probably your setup could work just fine for your to test the sliding ring but it will not last long, I suppose - first the sling will wear the ring and then the ring will wear the sling and it will snap. If you like the idea you should use a 316 (marine grade) stainless steel ring and Dyneema rope in your final setup. The rope can be spliced and you can tie nice knots with it which is not possible with the sling. Why are you using sling instead of rope? The Dyneema rope is easy to find and not expensive at all, I bought 3m of 4mm Dynemma for 7 euro and it will be enough for several years of kiting.

I have 4mm, 6mm and 8mm rope here, heaps of it in fact, that sling is also dyneema and knots quite well.

I used the flat sling because it was easier to feed through the inside of the spreader bar setup, didn't interfere with the harness buckle and it felt to glide over the ring with less resistance than the rope.
It also looses less strength when rounding corners than a round rope as path lengths are not as different for inside and outside of the bend.
I also figured that it may wear the ring less because it has a larger load bearing area.

I don't think that the ring will wear quickly unless it corrodes once the anodising starts to wear off, but if rinsed in fresh water after use it shouldn't corrode, it should just shiny up like climbing gear.
Prepared to be proven hopelessly wrong though.

Seeing some of the setups in this thread goes to show that real life forces must be much lower than appear at first thought, probably due to the very squishy nature of humans limiting any peak forces.




As an aside, dyneema can not be dyed colour, so the coloured parts of so called dyneema rope is actually nylon.
Straight dyneema is white and is also bloody slippery and doesn't hold knots well.

Hi Dimi sup that is really helpful info there and is basically what I'm lookin to do with my setup, I had considered plastic tubing to coat the cl but I now think there is no need, I now just need to get a hold of some welding gear or an old Naish cl that I can butcher, thanks again the long Cl is in my case pointless and has been giving me the sh#ts for a while now

Here is a new dakine nitrous short harness i found in my stock.

Why not hook the chickenloop up as pictured and cut the hook off?

You could buff it to a polish finish at the front where hook is cut off and leave the 2 tig weld divetts ( 2mm high polished tig welds)at the rear of the bar to keep the chicken loop centralised when required.
And use a short leash attached to the side.

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Absolutbeginer said..
I used the flat sling because it was easier to feed through the inside of the spreader bar setup, didn't interfere with the harness buckle and it felt to glide over the ring with less resistance than the rope.
It also looses less strength when rounding corners than a round rope as path lengths are not as different for inside and outside of the bend.
I also figured that it may wear the ring less because it has a larger load bearing area.

I understand your point but the sling is lacking the main advantage of the spliced Dyneema rope - safety. My rope had some signs of wear after 100+ sessions but nothing to bother me and then suddenly after one extensive session it looked like on my first picture (outer sheath completely snapped). Since then I believe that spliced Dyneema where the buried tail goes through the whole length is the best solution as far as safety is concerned. If there are not sharp edges at the connection points the spliced Dyneema rope will always wear in the middle (where the most friction occurs) and you will be safe to finish your session if the outer sheath snaps.

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Absolutbeginer said..
I don't think that the ring will wear quickly unless it corrodes once the anodising starts to wear off, but if rinsed in fresh water after use it shouldn't corrode, it should just shiny up like climbing gear.
Prepared to be proven hopelessly wrong though.

The protective anodising of your ring means that the core is 100% not corrosion resistant. Soon or later the anodising will wear, the core will start to corrode, become rough and it will eat your sling in a few sessions. My assumption is based on the 2014 SS RPM metal pulleys/sliders recall. Only a few months after they were introduced Slingshot replaced them with the proven plastic Ronstan pulleys because the metal pulleys ate the bridles. These metal sliders looked very similar to your ring - light metal with protective anticorrosion coating (like some climbing gear).


So, why bother with an anodised ring and not use a proven marine grade stainless steel one which will last forever and will wear the rope very slowly if properly polished?

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Greenarrowz said..
Here is a new dakine nitrous short harness i found in my stock.

Why not hook the chickenloop up as pictured and cut the hook off?

You will never achieve smooth sliding with that setup, it will be more an erratic quick movement from one side to the other, the release of the CL will be slowed and there are some chances the CL to jam especially if close to the spreader bar ends during QR. This setup is not completely safe and definitely you will get very poor sliding functionality.

This theead makes more sense with diagrams

www.ropebook.com/information/vector-forces/

Not as simple as that, 'monkey man', if you tie the rope in a loop, vectors change for the worse.
Much higher forces then, but otherwise a really good link for those struggling with the idea.

I'm guessing Dimi, that those recalled fittings were never washed after use, so manufacturer was pretty silly to use them.
Having never seen any other sliding setup apart from the commercial one, I went with the larger diametre ring for less friction as the commercial one used a wheel so I figured that friction was important.
Also not really knowing what forces were involved, I tried to stay away from a tight rope scenario and stainless in that size would be bloody heavy and expensive compared to using what I have to hand.
It was pretty obvious early on that a looser rope was sort of go to one side, stick, go to the other side action unless friction was minimised.

I'm glad this thread come along, I thought that I was just a loner mad scientist type until I see that heaps of others have had similar ideas.
That sling is not simply a flat thing, it effectively has two sides so it it is sort of a flattened tube, so wear should always be on one side and never be in a position to break without warning.

Next time I am near a boating shop I will have a look around at what sort of fittings are available.
In the mean time I will put the kite in the air and see how this one responds.
I would like to have a setup that is not critical of setup to work properly, so I will continue down the larger diametre road for less friction.

Seems flying lines are only rated at 300-400 kg, so that eases the strength requirement somewhat to what I assumed.

Hi all, dont post much but but wanted to give a heads up on what happened to me.

So nice thread TerryMcTool, Ill have a good read of this.

Been kiting since 99 and used Dakine Fusion seat harness always hooked for a good 10 of them years.

Second time my hook snapped of fell 40 feet, the last time onto my back, badly winded, could feel something was broken at the back of my shoulder but no one on the beach could see anything out of shape so decided to walk it off.

2 years of a strange numbness with a discomfort when sitting in a high back, the area now has started a burning pain bad, pinched nerve Im told. (you would not go to a hospital either if you had been treated like I have there)

Im probably going to have surgery when my private kicks in.

I have 3 points, one, DONT use Dakine harness, two probably good idea to learn unhooked even if you hate doing it, I still had hold of the bar when the hook broke but chose to take my chance with the free fall. Three , avoid public hospitals.

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<div>
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<div>Here's a photo of my bar setup. I played around with this a while back, but now forced into using it by my dynabar sliding hook breaking after 2 years of solid service (check for wear in those welds!).

After reading this thread, I decided to use two loops of dyneema. Doesn't impact performance in any way and I figure it reduces chance of breakage by exactly 50% ... pretty unlikely both will break from wear at same time.

Right now I am hooking chicken loop in, but when using the Ocean Rodeo bar, can also directly hook onto steel ring with the canvas webbing used for chicken loop release mechanism. Advantage here is to getting the bar a few inches closer buys a few more inches effective throw ... which may be the ticket on the day when over powered on the 17m.

Kite leash attached to either the blue loop on bar or the shackle attached to harness webbing. I prefer the attachment direct to webbing, as that's one less thing that can go wrong.

One negative of this system....carabiner launching is slightly more hassle. Need to work out a quick attachment that can be done blind....then it might even be an improvement over regular where you have to take eyes off the kite for a moment. Someone mentioned a locking carabiner....will investigate.

Other negative: with no hook and donkey dick, you lose that one final manual release, should chicken loop mechanism fail. Dynabar builds in a quick release for the rope slider ... if concerned, could build that in.

And then one further minor point....pad tends to rotate up or down depending on where rope is on the bar and where bar is in the pad. That may be specifics of this particular bar and pad....more experimentation needed.

A little more information about my setup. Having 2 ropes has a definite advantage. Peace of mind and doesn't impact on performance. The shackle, being metal, runs smoothly along the rope and there is no potential wear on the chicken loop. The shackle has a swivel so untwisting your lines is super easy. The safety line also spins easily with everything else.

Great thread interesting to read and see ingenuity and alternatives.
I got nothing different in a rope slider dyna bar sytem apart from running a back up rope slightly longer.
Had avoided a ring because of wear but now reading 2x rings work I'm sold.
Rings a winner over hooks if ya gotta paddle a board in.

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Absolutbeginer said..
Not as simple as that, 'monkey man', if you tie the rope in a loop, vectors change for the worse.
Much higher forces then, but otherwise a really good link for those struggling with the idea.

I'm guessing Dimi, that those recalled fittings were never washed after use, so manufacturer was pretty silly to use them.
Having never seen any other sliding setup apart from the commercial one, I went with the larger diametre ring for less friction as the commercial one used a wheel so I figured that friction was important.
Also not really knowing what forces were involved, I tried to stay away from a tight rope scenario and stainless in that size would be bloody heavy and expensive compared to using what I have to hand.
It was pretty obvious early on that a looser rope was sort of go to one side, stick, go to the other side action unless friction was minimised.

I'm glad this thread come along, I thought that I was just a loner mad scientist type until I see that heaps of others have had similar ideas.
That sling is not simply a flat thing, it effectively has two sides so it it is sort of a flattened tube, so wear should always be on one side and never be in a position to break without warning.

Next time I am near a boating shop I will have a look around at what sort of fittings are available.
In the mean time I will put the kite in the air and see how this one responds.
I would like to have a setup that is not critical of setup to work properly, so I will continue down the larger diametre road for less friction.

Seems flying lines are only rated at 300-400 kg, so that eases the strength requirement somewhat to what I assumed.

Mate, I'm taking your bait...
Explain what you mean by "tie the rope in a loop" ?

I thought the monkey-man link was a great explanation.

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JacobMatan said..
I am glad that this thread has been started as I have been meaning to bring it up here for a while. I have been using my customised sliding spreader for about a year now and I love it I wouldn't go back to a fixed hook. I have included a pic below, I use 3 pieces of 500kg dyneema one of which I keep a little looser than the others so that it wears last and is the safety, I have tied these directly onto the spreader bar, I then use 2 rope sliders lashed to a piece of hook that I cut off. Overall it makes for a nice smooth ride. I keep an eye on the condition of all the components, the line needs to be replaced about every 3 months or so depending on how much I have been kiting, the other parts require little to no maintenance.

I like the setup but the only problem I have with it is the extra reach that it adds which can be uncomfortable in powered up conditions. After reading this thread I think I will swap the hook to 2 rings. I had been worried about one ring breaking the chicken loop as it does not spread the load like a normal hook but I guess 2 rings would be ok.

I had also been worried a bit about using a direct connection. I guess really when it comes down to it if your CL jams when you really need it whether your on a hook or a ring your kinda screwed either way. At least with a direct connection you are constantly checking your release and keeping the parts moving.

Using rings would take a very small amount out of the reach but it won't really solve the problem. I need to get a much shorter chicken loop or customise my own chicken loop. Does naish do a smaller chicken loop?

I like your thinking and setup. However, I'd definitely change to a ring, there really is no reason to believe that a modern chicken loop that has passed the French release load tests will "suddenly" fail, especially if you use it every time you kite to connect and self land. You will gain some reach and you should look at some of the other ingenious ways that people have removed the chicken loop (BUT kept the release), to gain even more reach.
Another option is to switch kites at some time to ones that have a shorter/faster depower throw, like some wave kites. Most freeride kites are not like this though.

Lost dog, no baiting there, just most people don't understand the physics going on.

Now that you have the two separate arms configuration in your head and can get a feel of how vectors work it is just an extension of the same principle.
If you do as I and some others have done and tie a loop instead of the line being tied to either side of the spreader you simply change the vectors again.

Imagine that there is no spreader bar and that you are looking at two anchors like in the monkey link.
First imagine that those yellow dots are free to move around rings you can thread a rope through.
Now make a loop of rope that goes through both of the rings so that it forms a triangle with the load and then pull on the load, you will find that both rings will pull towards each other, and that the angle they adopt will split the difference between the load and the bit of rope horizontally between each ring.
This act now changes the angle or vector that the forces are acting on the anchors.

With the setup in the link, the load angle/vector on the anchors (little yellow dots) is simply the angle that the rope heads off towards the load, and the shorter the ropes to the load gets, makes those angle get closer and closer towards the dangerous infinite force straight line between the two anchors.

With the triangle setup, the bit of rope between the two anchors applies another force to the anchors equal in force to the force that the load is applying, so now these two forces add together to create a new vector angle that splits the difference between the two lines of rope. See diagrams.
The blue lines indicate the vector angle of these combined forces for the triangle setup.













Now remember that the wider this angle is, the greater the load applied to the anchor.
You will see by the diagram that the vector angles are much wider in the triangle setup versus the vee setup.
In the climbing world the triangle setup is known as the 'American death triangle' because of the high forces developed doing horrible things like pulling high rated anchors clean out of the rock or breaking slings etc.

Now any rope friction at the corners will tend to turn the triangle to some extent towards the V configuration and shift the vectors slightly favourably downwards.
So a simple setup suddenly gets very complicated to predict without using load cells to measure it all.

So what I did was consider the worst case possible and assume that there was no rope friction and make sure anything I used exceeded the forces calculated.
Don't like the idea of being dropped into the water from a height.
My choice of 90 degrees was a compromise between sliding goodness and a nod of respect towards the dangerous vector gobbledogs.
Note that had I tied off to each side then the forces would have been much lower, almost a third of what I ended up with.

I would have tied off to either side of my spreader bar, but the knots would get in the way of the harness buckle.

So keep in mind when creating your own custom setups that small changes in configuration may bring surprising results, and not always in your favour. . . . .

Hi, I design JAY equipment and I was informed by our distributor KITEPOWER about this interesting topic.
The DYNABAR has 2 holes and one is used for the sliders. The one below is for an additional dyneema leash to insert the ring and to attack a short leash. This setup is safe and was discussed in kf.com some time ago.
My contribution is this: the new dyneema leash is specially spliced and if the external layer breaks the internal will keep the load and won't slip and release the hook. Nevertheless check it and replace before it it breaks. Another check is the protective plastic sleeve and replace it if broken. We will supply new leash to Kitepower next order.
Another suggestion is not to use sliding rings because too much friction wears the dyneema quickly, we offer rings with pulley and bearing ball with ring.

Hi can you say something about how tight is the dynema rope supposed to be?

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jaystore said...
Hi, I design JAY equipment and I was informed by our distributor KITEPOWER about this interesting topic.
The DYNABAR has 2 holes and one is used for the sliders. The one below is for an additional dyneema leash to insert the ring and to attack a short leash. This setup is safe and was discussed in kf.com some time ago.
My contribution is this: the new dyneema leash is specially spliced and if the external layer breaks the internal will keep the load and won't slip and release the hook. Nevertheless check it and replace before it it breaks. Another check is the protective plastic sleeve and replace it if broken. We will supply new leash to Kitepower next order.
Another suggestion is not to use sliding rings because too much friction wears the dyneema quickly, we offer rings with pulley and bearing ball with ring.

In any case the anchor points should have a smooth radius and not just dyneema through a drilled hole at an intense angle.
Why not run a small 5 - 10mm pulley shaped radius or small pulley at the anchor point on each side of the plate?
I just bought a v8 dynabar and im going to modify the nasty rope through the hole design that cuts dyneema fast.
What a primative concept.
Its not hard to eliminate the dyneema cutting problem.
If modification is to much work a refund may be a better option.
Why not just design the V9 dyna bar with a horizontal pulley at each side instead of the rope through the hole ?
You could set the rope up as a triangle and let the pulleys share the wear along the dyneema vastly increasing the service time and most of all safety for people using the product.

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julitor said..
Hi can you say something about how tight is the dynema rope supposed to be?

If I'm understanding the jibber-jabber correctly, the tighter the rope, the more load is applied to the end of the spreader bar.

I don't actually think this is a problem... the spreader bar is part of the chain of anchorage, not the terminus. Surely that spreads the load further than just the "arms"?

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Greenarrowz said..

In any case the anchor points should have a smooth radius and not just dyneema through a drilled hole at an intense angle.
Why not run a small 5 - 10mm pulley shaped radius or small pulley at the anchor point on each side of the plate?
I just bought a v8 dynabar and im going to modify the nasty rope through the hole design that cuts dyneema fast.
What a primative concept.
Its not hard to eliminate the dyneema cutting problem.
If modification is to much work a refund may be a better option.
Why not just design the V9 dyna bar with a horizontal pulley at each side instead of the rope through the hole ?
You could set the rope up as a triangle and let the pulleys share the wear along the dyneema vastly increasing the service time and most of all safety for people using the product.

Do post up your solution, it sounds interesting.

Kamikuza, just saying if the rope is tighter then the force it has to carry becomes much much larger,
In simple terms, try doing a pulp with your arms going straight up above your head. - should be easy/doable depending if you are a lawnmower or not.
Now try this with your arms going out at 30 degrees. - much harder
Now try it at 60 degrees....

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In any case the anchor points should have a smooth radius and not just dyneema through a drilled hole at an intense angle.
Why not run a small 5 - 10mm pulley shaped radius or small pulley at the anchor point on each side of the plate?
I just bought a v8 dynabar and im going to modify the nasty rope through the hole design that cuts dyneema fast.
What a primative concept.
Its not hard to eliminate the dyneema cutting problem.
....

Dynabar is designed to be as simple as possible and offer more features, holes are there to attach steel sliders too.
I admit the hole edge his a bit sharp but it is due to polish process. No drill holes, the design and mould has rounded edges, check not polished side, and in next production we ask the factory to smooth hole edges after polish.
We already have different solutions also using bearing ball but we should also keep the price low. I will post some pictures later...

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jaystore said...
Hi, I design JAY equipment and I was informed by our distributor KITEPOWER about this interesting topic.
The DYNABAR has 2 holes and one is used for the sliders. The one below is for an additional dyneema leash to insert the ring and to attack a short leash. This setup is safe and was discussed in kf.com some time ago.
My contribution is this: the new dyneema leash is specially spliced and if the external layer breaks the internal will keep the load and won't slip and release the hook. Nevertheless check it and replace before it it breaks. Another check is the protective plastic sleeve and replace it if broken. We will supply new leash to Kitepower next order.
Another suggestion is not to use sliding rings because too much friction wears the dyneema quickly, we offer rings with pulley and bearing ball with ring.

Thanks for an awesome product... Been using the V7 for a few years now ( had experimented with several home made setups in the past as some have above )

Question:
when will the winged pad be ready for sale ??

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flyingcab said..
Kamikuza, just saying if the rope is tighter then the force it has to carry becomes much much larger,
In simple terms, try doing a pulp with your arms going straight up above your head. - should be easy/doable depending if you are a lawnmower or not.
Now try this with your arms going out at 30 degrees. - much harder
Now try it at 60 degrees....

Yes, understood. But I don't think it matters, considering the whole system of SB and harness. The load increase on the anchor points, but that is distributed around the whole loop of harness and SB. The SB keeps the sides of the harness apart, so whatever load is on the hook is not pulling the harness sides together and squeezing your guts out.

Be interesting to see how much force is need to bend the spreader bar... I bet it's more than up to the task.

Whatever load placed on your anchor points is transferred there by the rope.
So higher forces need stronger ropes and better attachment points if attached to each side and even stronger rope and smooth radius if doing the loop.

Yes the spreader bar will effectively isolate the forces from the rest of your harness, apart from the deformation allowed by the spreader bar itself, so you will feel the same pull on the harness as a standard setup.

Putting pulleys on each side and doing a loop will make the highest forces configuration possible and the pulleys will have to take a couple more times force than the kite delivers.

I suspect that a spreader designed with nice radiused holes to take say a 8mm chord so the angle could be wide for slidy goodness and using a nicely oversized pully would be the ultimate setup.
If somebody is going to manufacture one, I'd like to see the spreader plate made with and outward bend either side to create a bulged front area that allows the rope to enter into the plate without a bend and also allow easy inspection of knots as they are on the outside.

I also suspect that the ideal rope tightness would allow the force vector created at the kite attachment point to point towards the centre of the spreader bar, that way the pulley would not have a tendency to snap suddenlyfrom one side to another.

I've been using this set up for a few seasons, IMO the only advantage of the Dynabar (I have the V8), is if you want to have it set up to unhook.

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Absolutbeginer said..
Whatever load placed on your anchor points is transferred there by the rope.
So higher forces need stronger ropes and better attachment points if attached to each side and even stronger rope and smooth radius if doing the loop.

Yes the spreader bar will effectively isolate the forces from the rest of your harness, apart from the deformation allowed by the spreader bar itself, so you will feel the same pull on the harness as a standard setup.

Putting pulleys on each side and doing a loop will make the highest forces configuration possible and the pulleys will have to take a couple more times force than the kite delivers.

I suspect that a spreader designed with nice radiused holes to take say a 8mm chord so the angle could be wide for slidy goodness and using a nicely oversized pully would be the ultimate setup.
If somebody is going to manufacture one, I'd like to see the spreader plate made with and outward bend either side to create a bulged front area that allows the rope to enter into the plate without a bend and also allow easy inspection of knots as they are on the outside.

I also suspect that the ideal rope tightness would allow the force vector created at the kite attachment point to point towards the centre of the spreader bar, that way the pulley would not have a tendency to snap suddenlyfrom one side to another.

Assume a 100kg kiter, how many G can be pulled at the hook? The Amsteel is rated to what, 1,800kg? I think there's plenty of safety for breakage, but as its been said, the rope/SB interface is what will wear and weaken the rope... perhaps a nice raised, rounded collar around the hole? Then we could eliminate the nylon grommets...

More angle may lower the load on the rope, but I don't like how it feels -- I prefer tighter ropes