Trying to Understand the Pendulum Effect & Relationship with Zero Off

[Stevie Boy]

Hi Good people, I have been looking at the Zero Off Matrix, trying to understand why so many people use A2, looking at the Matrix, where th Zero Off picks you up, duration and intensity of the load.

I am thinking accelerate and achieve a good load into the centre line and release energy outbound B2 ,B3 and any of the C settings look a better option on paper, than A2

So why do so many skiers prefer A2 with later pickup with a longer duration of potential load.

I may have the wrong concept, when viewing the Zero Off Matrix/Graph, please put me on the right path.

[Jody_Seal]

latter pick up helps keep the line tighter out to the body line.

also allows for the skier to better keep handle control off the turn and into the load phase.

 

also these 450hp sleds need some sort of dampening.....

 

I like the first answer better but the second is probably more to the truth of the matter.

[Broussard]

From what I have seen the Zero Off settings that are most popular have changed throughout the years.

 

As Jody mentioned there are some key changes that have been made regarding power plants:

- 5.7L engines have been replaced by 6.0L and 6.2L engines.

- Additionally the older engines were MPI while the new 6.2L engines are GDI

[Adam Caldwell]

We need something new.

 

[MISkier]

I was just doing some experimenting with a different setting this year that was somewhat enlightening to me. If it bears out over the next couple of sets, I may have more detail to share.

 

The big tradeoff for me was getting free of the boat versus tight line into the buoy. That is probably where your technique preferences and the ZO setting need to intersect.

[6balls]

C all day long pick me up off the ball and bust it to centerline.

[ETskier]

S version upgrade with single puck is diferent too.

[MISkier]

So, I just confirmed that my conclusions about my settings experiment seem to be accurate. At the very end of last season, I changed my setting from C2 to B2 to see the effect. There were only a few ski days left and the cold water was already upon us. So, my skiing had regressed some from that anyway and I was not sold on that change then.

 

At the start of this season, I decided to keep it at B2 and evaluate it. I was struggling right from the onset. Could barely run my opener more than a couple times per set and it felt like a ton of work - always narrow, always late, feeling pulled forward after the wake and into the buoy for some terrible turns. I thought I was rusty, but also searching for the root cause. A few days ago, I decided (after my first disappointing set) to switch back to C2 for the second set. Amazing. I ran all the passes in the second set and just completely smoked most of them. It wasn't even close and some even felt easy.

 

My working theory is that my preferred technique is to have the boat work with me from the ball to centerline (just like @6balls said) and then allow me to be free of the boat's pull through edge change and preturn. With the other setting, the boat feels like it is still "on me". I am losing width, direction, and body position, as it pulls me downcourse and tilts me over toward the boat on my ski when I don't want it to. I stayed with my C2 setting tonight again to test my theory and all was well. So much better.

 

I never thought I would be as sensitive to a pull setting as I have appeared to be, but the difference is unmistakable.

 

I must also acknowledge the many skiers who have posted their disdain for ZO and their preference for PerfectPass. I dismissed much of that and now have a little insight into what they may have been experiencing. I still prefer ZO over PerfectPass, but am more aware of the impact of the pull settings than I was before.

 

@Stevie Boy, you just need to determine how you want to use the boat for that pendulum effect and when you want to have it apply power and when you don't. The duration of your work zone and your overall power needs after the wake can be as important as how quickly and intensely you are picked up from the ball. I really doubt that I would use an A setting, but have always wondered about it, given the frequency I see it selected by the pros.

 

Good luck.

 

 

[Slalom.Steve]

@MISkier - what boat/engine are you skiing behind?

[MISkier]

@SlalomSteve, 2022 Nautique 200 with 6L engine.

[GSchmid]

I just repowered my CC 196 with an Excalibur 343 w/ZO. After years of Stargazer, the biggest difference I feel is how the boat picks me up off the ball. It's much easier to control the line in and out of the turn, and the work you put in at the first wake propels you wide and early. I'm using C2, and I'm loving it. I tend to be a "strong puller"; always been able to get in (and hold) a good leverage position. Having a tight line to load against allows me to exploit this strength.

[Mastercrafter]

@adamhcaldwell I’m curious what your “something new” would look like. This is not said in an argumentative way.

[ScottScott]

What is just as important as "when the boat picks you up" is what happens as a result. I think what the the A settings does that works well for people is the sling across the wakes you get when the boat compensates. The A settings allows the boat to slow the most of all the settings. After the boat slows and picks you up it then has to speed up above the set speed to maintain the proper time from buoy to buoy. That means a significant acceleration from the time it picks you up until it is just as much above the set speed as you had dropped below the set speed. That acceleration helps you gain speed across the wakes. The C settings will force you to generate more of the speed yourself. Of course the later and more adjustment that has to happen with A means it will be on you longer, but with the speed it has helped you generate across the wakes, you should be free of the boat at that point anyway, and at short line a little extra after the wakes to get you up next to the boat could also be helpful.

[6balls]

Ball to wake is easier, technically, then properly skiing wake to ball. The best skiers are better than most of us wake to ball, and perhaps can take advantage of settings to their liking.

I give juice to the boat off the ball to wake, and "C" gives it back to me--got me down the line to the extent that I could.

I tried every setting--ran nine 35's in a set. Still settled back on "C". To each their own--try 'em all and pick what works best for you.

[Slalom.Steve]

I wonder... an issue that all skiers face at least some of the time is slack line out of the turn. So wouldn't it be advantageous to have the boat actually do it's accelerating when we're *not* under line load (ie at the turn), so that the boat is moving away from us and pulling any slack out? If that's the case, perhaps the late and long pulls of A1/A2 achieve more of this?

 

Please note - I don't really have any idea what I'm taking about, just thinking out loud. All of this needs verification or rebuttal from someone with more knowledge/skill than me.

[Stevie Boy]

.

[ToddL]

@ScottScott - "[the boat] has to speed up above the set speed to maintain the proper time from buoy to buoy".

 

Yep. That is what I hated about all of the published ZO setting charts. They didn't express this fact visually.

 

Imagine a graph where the horizontal axis is time and the vertical axis is speed. Assume as the skier rounds the buoy, the speed is perfect and the time starts there. The next thing we'd expect to see is the impact of the skier loading the line. This would mean the graph would move lower in speed a dip under the perfect reference line. This dip would continue to get deeper if nothing happened. Based upon the ZO setting, eventually the boat would sense this reduction and would start to correct it. Initially, the correction will just "flatten" this negative curve and then eventually bring us back up to the perfect line. However, the process is not yet done. The area under the perfect speed line represents the amount of lost speed/time. This has to be countered with a equally sized area of time and speed above the perfect line so as to cancel it out and get a total perfect speed/time segment. The shape of this correction area/curve above the line doesn't have to match the other one. Only the area does.

 

So, now consider a larger, crank-the-turn skier with an A1 ZO setting that is late to react and doesn't react with a lot of throttle intensity. The skier's effort is a big deep curve under the line. The corrective action is delayed and ramps up slowing. Thus, it will take a long time to negate that, meaning the throttle is elevated for a much longer period, possibly all the way to feet before the next buoy.

 

Let's consider the opposite scenario: A light skier barely pulls the boat down and the C3+ ZO setting is one that reacts quickly and powerfully. This skier might create a small area/curve under the line but the boat will recover abruptly and quickly, possible back to true speed before the centerline.

 

The literature on ZO settings also describes the throttle response in terms of symmetry or asymmetry. B is considered symmetrical in that the rate the throttle comes on is the same rate that it comes off. (Depth of throttle used is based upon what is needed to recover and counteract the skier's force.) The A setting is asymmetrical in that it ramps up the throttle slower than B, but will ramp off the throttle faster than B once the corrective event is completed. The C setting is also asymmetrical. but it ramps up faster than B, but then will taper off slower than B at the end of the corrective event.

 

The numbers are actually harder to understand. It is the gforce target at which the throttle starts to back off on its corrective action. Some think of this as intensity. I think of it as the timing of the throttle release curve. "The lower the number, the sooner the skier will feel a reduction in the intensity of the pull from the boat." (taken from USAWS Speed Control Zero Off Presentation) In other words, it is the accelerometer sensor that tells the speed control that the skier's load has dropped to the level indicated by the selected number and thus the throttle roll off curve of the selected letter can begin. This is the one that takes a while to wrap one's head around, and I may not have it exactly correct. Still, to me a number 1 setting means the the throttle roll off curve will happen later because the skier's force has to be negated more before that can happen.

 

Referenced above: USAWS Speed Control Zero Off Presentation See slides 18-30

 

[Stevie Boy]

Thanks all for the input, so basically the Zero Off Graph, is not that useful in determining what Letter/Number would be most suitable for the task, it,s more about individual technique, feel and what works for you.

Because somebody suggests you would be better off with a specific setting, they may not be helping at all, because they cannot feel what you are feeling, I was persuaded to go A2 but always felt that I was not getting the space, that I had on B1,B2 or C1.

Time to re-visit and stick with whatever, feels right for me.

[ScottScott]

In concept, C seemed like something that would work well for me. I have tried it just a couple passes, not only did I not run any passes but I fell on half of them. I didn't get the speed or width I was used to. A change from B to A went very easy for me. The different settings certainly take some adjustment, and I think going from A to B, or B to C, or certainly A to C takes more adjustment than moving toward A. The timing of edge change is different. I think with C you will need to delay your edge change a little, where A gets you faster across the wake to an earlier edge change. One isn't necessarily better than the other, but changing can take some time to adjust.

[scoke]

Some folks are visual. Some folks are feel but either way we need to understand how the system is designed, reacts and works.

 

From this link: schnitzskis.com/zerooff.html

 

 

For the non-engineers, a sample graphic:

 

 

Or for the engineers which this might be more accurate and similar to a bending moment diagram or load flow diagram:

 

 

[ScottScott]

I'm not too sure about that 1st graph.

[scoke]

Scott,

 

Taking it out of context, it's misleading.

 

I'd recommend comparing it to the B and C graphs and the write up at the link. There might have been an overlay done with A-B-C at the link but it's been quite a while since I built researched, polled big dawg skiers and built that.

 

Curious what you think after some reading.

 

[Mastercrafter]

@scoke for some reason your link doesn't work when clicked, but copy+paste does.

[Slalom.Steve]

@SkiJay, when you gonna release the "Zero Off Whispering" book? :D For how much I've read about it, I feel like I still don't really understand. Or more accurately: I understand "what ZO does" on paper, but I don't understand how that translates to the actual feel on the water, or what the hell setting I should use lol.

 

I feel like the danger even with trying a variety of settings to find "your setting" is you may just be best at whatever setting you were using previously, since your technique will have adjusted to that setting.

[Slalom.Steve]

Relevant other thread to reference: https://www.ballofspray.com/forum#/discussion/19906/what-zero-off-settings-do-you-use/p1

[6balls]

@scoke post above in terms of graphical representation helped me to understand best what ZO does. Thanks for re-posting.

I’m trying all settings it is also what I “felt” on the water—only cuz I tried em all.

I’m a powerful dude who has a bad habit cranking turns especially 2 and 4 then pulling like an ox. C picks me up quick and gives me plenty of energy to manage early wake to ball—just wish I were better at that aspect. Wish I had known more at a younger age—I think I cudda been pretty good.

To each their own on settings to match your style and get more buoys.

[VONMAN]

Back in my late 58-62 (age) I was at C-3, 34mph. Skied strong and loved to be picked up right after turning the ball. Now at 71 (72 in July) I'm find myself at A-3, 32mph and in total control of the boat instead it over controlling/over powering me. Big change, but so have I. Don't get old, Ha!

[Stevie Boy]

When the Boat picks you up ? Does the boat have to feel resistance before it initiates your chosen power curve, another variant, depending on skiers speed around the bouy and ability to head back towards the wake, surely a skier who is not so good at maintaining speed around the bouy, will get picked up sooner, for the same setting.

Again individual requirement depending on skill set.

@VONMAN could be a good example C3 and A3 power curve are similar, they are just initiated at a different point with the possibility of A3 giving more gas due to the delayed pickup.

 

[MISkier]

@Stevie Boy, the boat responds with the selected curve when the skier loads it. As you mentioned, individual skiers will load the boat at different points. That is certainly one factor to which setting a skier will choose.

[VONMAN]

@Stevie Boy Bingo.

[SCOT]

I would like to see a chart that a skier can select his/her style, considering weight, boat speed, line length.

With that in mind , ideal settings for 215 lb skier with aggressive and rushed turns who loses ground from 2nd wake to buoy at 34 mph, 32 off?

[MISkier]

@SCOT, what setting are you using now?

 

[coach3]

I am a older, ugh seasoned skier, and now skiing A3 as well. It allows me to do all my "house keeping" after a turn for a later pull and A3 waits on me. However, driver technique on skier pick up is as much or more than zero off.