Club Boat and Power, ZO

[Beezer]

How is ZO affected by the HP of the motor in the boat skied behind???

I ski behind a 2011 nautique 5.7 on a 6-8 set a weekly basis on A2. Most all of our local tournaments are behind newer Master Craft large motor boats.

A2 Never feels the same until 3-5 passes later. Im not sure what I’m adjusting to,  but I know it’s me. When I go back to my home boat, everything feels slower. Some of that feeling is being back at my home site but the pull of the boat is softer “easier to manage” or smoother. At times I question the BOAT SPEED to  the driver when I GET BACK. 

Do I need to run a different setting on ZO on the smaller motor boats to make it feel like the larger motor boats that I ski on in tournaments? 

[Jody_Seal]

it's not HP it is torque..

the big boats with big engines have nearly 465 ft pounds of torque. that much torque does not allow for much skier impact like a 375 foot pound small block chebby..

I had this conversation last week with a very good slalom skier, I suggested running in practice mode and upping the speed a tick or two.. instead of 16.95 run 16.80.. 

 

Edited October 20, 2023 by Jody_Seal

[Beezer]

3 minutes ago, Jody_Seal said:

it's not HP it is torque..

the big boats with big engines have nearly 465 ft pounds of torque. that much torque does not allow for much skier impact like a 375 foot pound small block chebby..

I had this conversation last week with a very good slalom skier, I suggested running in practice mode and upping the speed a tick or two.. instead of 16.95 run 16.80.. 

 

Interesting… So did you think to ask if line length mattered or had an impact?

If I up the speed, will that adapt for line length the same way, At  the same ZO setting? Or would going from A2 to A3 achieve the same goal?

[LeonL]

5.7 200's are pretty soft.

[markn]

Try adding (+) on your Nautique 200 to get a firmer pull.  I run C2 on the 6.2 Nautique, but run C2+ on my 5.7 196 to get the same feel.

[Mastercrafter]

As Mark said, + setting helps. 
 

I found myself in a similar situation with my 5.7 Prostar versus all the slightly newer 6.0 and 6.2 boats. I ended up buying a 3 blade jump prop for the Prostar, it firmed up the pull and made the boat come alive a bit. I will say though, the engine is screaming at 36mph.. about 4150 RPM. 
 

A friend joked and said “wow let me know how many buoys that gets you” and he’s right… but it makes me happy and it’s a little less to think about. 

[Beezer]

I’ll try the + settings.

[The_MS]

Move the letter. Have a driver do a blind test on you. 

[thager]

I ski C2 behind my 5.7L. For the 6.0L and 6.2L I drop down a letter and use B2. Experiment

and see what works for you.

[ProStah_Skiah]

17 hours ago, Beezer said:

I’ll try the + settings.

FYI, the response and intensity of the plus settings are all greater than any non-plus setting.

The progression is:

Slowest Response | A -> B -> C -> A+ -> B+ -> C+ | Fastest Response

Less Intensity | 1 -> 2 -> 3 -> 1+ -> 2+ -> 3+ | More Intensity

Also, the plus settings will have you enter the course faster (+1.6% speed instead of +0.75% speed).

[markn]

If you are used to A2, as to when, where and for how long the boat is on you, I submit, stick with A2 and add the +.  It will act as A2, but more intense.  Changing letters means changing when, where and for how long ZO is engaged.

ZO A,B,C is not how fast it responds, but rather WHERE it responds.

Edited October 21, 2023 by markn

[ProStah_Skiah]

2 hours ago, markn said:

If you are used to A2, as to when, where and for how long the boat is on you, I submit, stick with A2 and add the +.  It will act as A2, but more intense.  Changing letters means changing when, where and for how long ZO is engaged.

ZO A,B,C is not how fast it responds, but rather WHERE it responds.

ZO responds to skier load, not location in the course.

A has the slowest response to pull load, followed by B, C, A/B+, then finally C+ being the fastest response.

The numbers control intensity and duration.

[markn]

Maybe I can learn something new here, but having just re-read the ZO manual, in the language of the manual, while saying "it is when" not "where" ZO reacts, it goes on to say the various settings come on "where".  I recognize ZO will responds when there is load from the skier, but with the graph, it appears the load  "comes on" later on setting "A" than Setting "C".  To me, that describes "where".

If a skier likes a "load" right off the buoy, "C' loads immediately.  Conversely, "A" loads much later; based on the graphs.  If I load the boat right off the buoy on "A", the pull is completely different than if I load the boat right off the buoy on "C".  

I have attached the 2 pages from the ZO manual for reference.  Greatly appreciate additional insight on this.

ZO PDF 2.pdf ZO PDF 4.pdf

[LeonL]

I would say if using the word "where" it means where the skier is in relation to cross course, not down.  Then it kinda means the same as "when".  (If that ain't confusing enough)

[Beezer]

So I wanna see if I have this in my head correctly. Im a 165# guy, 28-32 off skier at this time and learning line control. The letter is a reaction time to my load on the boat and the number is the intensity LIMIT? So the higher number I go in the same letter will respond to my load with more intensity and continue to increase to the LIMIT, until I unload the boat and the boat returns to it set speed.

So what I want to feel for or find  is the settings thats give me the most width early and line control off the ball. Then I’m skiing with the boat in time???

[ProStah_Skiah]

Hi @markn I believe you’re correct as to your interpretation of the two pages that you attached.

My earlier post was directed more to the idea that A2+ will be same/similar as A2 but more intense. I think they will be very different. My read of that same presentation is that any + setting is more intense than any normal setting. In effect, the whole A/B/C; 1/2/3 matrix is offset to be more intense on + as opposed to normal.

See attached table from the same slide deck you referenced earlier. If you look at the values for A2 and A2+, you’ll see that the gate entrance speed is faster and the pull/release/gForce values are all much greater. Note that all of the pull/release/gForce values in the + matrix are greater than any value in the normal matrix.

FYI, this presentation references ZO rev R. Apparently ZO made some changes to the + settings in Rev S, but I do not know what they are.

Hope this helps?

[ProStah_Skiah]

13 hours ago, Beezer said:

The letter is a reaction time to my load on the boat and the number is the intensity LIMIT? So the higher number I go in the same letter will respond to my load with more intensity and continue to increase to the LIMIT, until I unload the boat and the boat returns to it set speed.

@Beezer, yes…the letter is reaction time, with A being the slowest and C+ being the quickest.

The letters also define the throttle profiles. A and C are asymmetrical. A has a slower ramp up and quicker release, B has a symmetrical ramp/release and C ramps up quickly with a slower release.

The numbers define intensity and duration, with 1 having the lowest peak & longest duration and 3+ having the highest peak & shortest duration.

@markn posted the chart that describes the throttle timing and profiles above.

[chrislandy]

I've found that skiers prefer A1 behind my prostar (5.7) when they ski A2 behind a 200 / Ski and visa versa so I think it's more likely that the hulls and engines react differently to the same (or similar tuned) algorithms of the ZO 

 

I've also found that having the course mapped properly makes more difference than any setting, we ski each summer on a lake with a floating course and up to a 10ft level difference over a couple of weeks (its a hydro power station lake). This year, at one point all of a sudden my son just couldn't run the course at all. I noticed the beeps didn't seem to sync with boat buoys, so remapped and it was back to normal, the course must have moved down the lake by a few feet with the level dropping.

[Mastercrafter]

2 hours ago, chrislandy said:

I've found that skiers prefer A1 behind my prostar (5.7) when they ski A2 behind a 200 / Ski and visa versa so I think it's more likely that the hulls and engines react differently to the same (or similar tuned) algorithms of the ZO 

 

I've also found that having the course mapped properly makes more difference than any setting, we ski each summer on a lake with a floating course and up to a 10ft level difference over a couple of weeks (its a hydro power station lake). This year, at one point all of a sudden my son just couldn't run the course at all. I noticed the beeps didn't seem to sync with boat buoys, so remapped and it was back to normal, the course must have moved down the lake by a few feet with the level dropping.

But from everything I read, this shouldn’t matter except for gates, as ZO is only supposed to react to skier load, not the boats position. Did speed during a few feet on the gate turn in make the whole course impossible? 
 

With no skier, ZO holds a very constant speed through the course. It doesn’t preemptively throttle up/down based on where the boat is. If it did, there’d only be one ideal line we’d all have to follow exactly in order to not get punished. 

[6balls]

@scoke you still have your ZO pictorial?  

[markn]

Certainly agree the gate speed increases with the +.  While "intensity" increases with +, no doubt, again, to me, an "A" setting, regardless of + or no plus, would respond like the graph indicates, but intensity changes...... unless the letter/number graph changes with +.  That would clarify my understanding.

[ProStah_Skiah]

My speculation, but here‘s why I believe that the graph does change with +

The chart is titled “ZO PULL - A/B/C - NORMAL” (does not reference +)

Notice on the chart, that the leading edges of the curves all line up for the A’s, B’s, and C’s. This would correspond to pull (response time) values of A=0.3, B=0.6, C=0.7 (higher number = faster response).

The pull values for A+/B+ and C+ are 1.0 and 1.4, respectively. Therefore, my assumption is that the + curves are all shifted to the left with respect to the normal curves. At least that’s my logic…

[markn]

Yep, the leading edge for each letter, regardless of number do line up.  If the + moves the curve closer to the left (buoy) the graphs  would still reflect  A,B,C?  Hence with +, a firmer A, B, C pull?

[Mastercrafter]

I'm amazed we can't just get someone from ZO / E-controls to hop in here and tell us what's up. Are we really force fed a speed control system and left with only speculation / best guess as to how it all works? Will we ever know if Rec Mode gives you the same gates as tournament mode? What does + actually change? ZO just states "more responsive pull".. but what is that? Quicker increase in engine RPM? Does mapping only affect gates? 

 

@FreddyKrueger  ... do you work for/with the E-controls folks? Can anyone chime in and tell us how this system works?

 

[chrislandy]

2 hours ago, Mastercrafter said:

But from everything I read, this shouldn’t matter except for gates, as ZO is only supposed to react to skier load, not the boats position. Did speed during a few feet on the gate turn in make the whole course impossible? 
 

With no skier, ZO holds a very constant speed through the course. It doesn’t preemptively throttle up/down based on where the boat is. If it did, there’d only be one ideal line we’d all have to follow exactly in order to not get punished. 

I'm only relaying what I've noticed. If you read the ZO manual it says about the A/B/C is when the boat pulls in relation to load, but it also says eg "A" will come in later after the buoy so I guess there is some relative to course aspect within the algorithm 

[Mastercrafter]

25 minutes ago, chrislandy said:

I'm only relaying what I've noticed. If you read the ZO manual it says about the A/B/C is when the boat pulls in relation to load, but it also says eg "A" will come in later after the buoy so I guess there is some relative to course aspect within the algorithm 

Surely not trying to be argumentative, just stating how I see it:

Obviously ZO knows where the buoy is, but I always understood that it really doesn't matter to ZO, it's all load/speed based. "Later after the buoy" is just a result of where the skier is and when they begin to load the line. If position in the course and load timing remain the same, A/B/C will surely be earlier or later after the buoy, but that's just driven off the skier and what they're doing. 

Otherwise someone running a wide, early line and backsiding the buoy would get a completely different pull than someone running narrow and down course. I've never felt a different pull when I'm scrambling to make up time. 

[chrislandy]

I think it's a product of the fuzzy greyness of how ZO works. 

The thing is, if you put it in slalom mode without mapping a course, it feels different to when it's in a course yet in theory if the pull is the same irrespective of where it is in the course then surely it should feel the same? and yes, I know in a mapped course it has specific timings it is trying to keep to and on an unmapped course it's probably just trying to keep the same speed all the time but who knows what and how the little black box works it out

[Mastercrafter]

59 minutes ago, chrislandy said:

I think it's a product of the fuzzy greyness of how ZO works. 

The thing is, if you put it in slalom mode without mapping a course, it feels different to when it's in a course yet in theory if the pull is the same irrespective of where it is in the course then surely it should feel the same? and yes, I know in a mapped course it has specific timings it is trying to keep to and on an unmapped course it's probably just trying to keep the same speed all the time but who knows what and how the little black box works it out

You have a point. It knows it needs to get a certain time at the end of the course, and it's never really wrong, so I would think at some point it has to make up for any cumulative error of speed + acceleration over distance. 

[DW]

3 hours ago, Mastercrafter said:

I'm amazed we can't just get someone from ZO / E-controls to hop in here and tell us what's up. Are we really force fed a speed control system and left with only speculation / best guess as to how it all works? Will we ever know if Rec Mode gives you the same gates as tournament mode? What does + actually change? ZO just states "more responsive pull".. but what is that? Quicker increase in engine RPM? Does mapping only affect gates?

Unfortunately when a company has a monopoly there is no incentive to allocate any resources for customer support.  Even more so when you can count the inquisitive ones on one hand.  Ironically, I recall getting the actual program tables from the Accuski guys for both learning and allowing the customer to do their own programming.

[Kelvin]

Which prop is on the 200?  If its an ACME 422 or 668, that 15.5 inch pitch is too much for the 5.7L engine.  

[Drago]

3 hours ago, chrislandy said:

I'm only relaying what I've noticed. If you read the ZO manual it says about the A/B/C is when the boat pulls in relation to load, but it also says eg "A" will come in later after the buoy so I guess there is some relative to course aspect within the algorithm 

It's not , Later after the  Buoy. It's Later after the Load.
@chrislandy answered @Beezer's question the best so far,

.I've found that skiers prefer A1 behind my prostar (5.7) when they ski A2 behind a 200 / Ski and visa versa 

 ℹ️ it's been 15 years since zo has been crammed down our throats, maybe @Horton can bring up the thousands of pages in the archives for some light reading.

[Horton]

Let me add that I think a good 5.7 200 (at sea level) should not a lot feel different from a 6.0 ProStar. 

Until I get to a 6.2 Nautique or 6.2 Malibu I think the ZO settings don't really change that much. Behind a 6.0 ProStar I can go from A2 to C1 without thinking much about it. Behind a 6.2 Malibu or Nautique letter and number make a much bigger difference to me.

On another note: as a 165 pound 28-32 off skier you are likely not angering the ZO too much anyway. ZO gives you back what you take away - nothing more and nothing less. The difference between the engines and boats is how the boat gives you the juice.  

[The_MS]

I’m have a 6.2 200 and ski behind a 5.7 prostar, 6.0 prostar, 5.7 196 and 2 different 200s with 5.3s and a 200 with the 6.0 
I use B1 on all of them and all feel good   Of course I have @Mrs_MS driving most of the time but my drivers are all good. When I was skiing events it was always the big engines in the Malibu that would have me moving to C1

 

 

[markn]

So once again, does my hypothesis still apply that with the + to A, you still get an "A" reaction to load only firmer and possibly a bit sooner?  If the hypothesis is true, then if one likes an "A" pull but wants it firmer, then adding the + is better than changing letter which would "react to load" later or more differently when looking at the graphs.  

A graph comparing a regular and a plus curves would answer the question.

Probably a bit too much mental masturbation, but I would like to know the real answer.

[Jody_Seal]

every one should draw a setting out of a hat, and with out looking hand it to the driver and go ski...

[Hockdog]

One more time…….

 

[Beezer]

6 hours ago, Horton said:

Let me add that I think a good 5.7 200 (at sea level) should not a lot feel different from a 6.0 ProStar. 

Until I get to a 6.2 Nautique or 6.2 Malibu I think the ZO settings don't really change that much. Behind a 6.0 ProStar I can go from A2 to C1 without thinking much about it. Behind a 6.2 Malibu or Nautique letter and number make a much bigger difference to me.

On another note: as a 165 pound 28-32 off skier you are likely not angering the ZO too much anyway. ZO gives you back what you take away - nothing more and nothing less. The difference between the engines and boats is how the boat gives you the juice.  

The whole reason for the post and the question, is I want to train on the ‘11 200 5.7 as close to a 21+ pro star 6.2. At my weight I figured it would be pretty easy to find a setting that would feel like the 6.2. I tried deviating from A tonight and quickly  figured out, that was not an option for me. C1 I could learn to use or test myself with but I need more time on it. A3 was money until I shortened to my hard pass and it felt violent (probably because I’m loading ZO more than I can handle). It’s becoming obvious that there’s no science to matching boats and power plants with ZO  otherwise you guys would point me to it. I dont think you can produce the power/torque of a 6.2 in a 5.7 with a different ZO setting. After tonight I think our boat has plenty of power to respond to my in puts. I just need to find ZO response curve that suites me best on my hardest pass. 

[Drago]

@Beezer, it won't feel great in one set. You're using a "soft" setting on a soft boat. Try B2 or B1-2+.

[chrislandy]

14 hours ago, Drago said:

It's not , Later after the  Buoy. It's Later after the Load.
@chrislandy answered @Beezer's question the best so far,

.

I've found that skiers prefer A1 behind my prostar (5.7) when they ski A2 behind a 200 / Ski and visa versa 

 ℹ️ it's been 15 years since zo has been crammed down our throats, maybe @Horton can bring up the thousands of pages in the archives for some light reading.

@DragoThats what I assumed mainly, but then had what happened this year. 

 

Also, from the manual

That might be a product of the typical load vs position of the course and trying to explain the effect of each setting, or it might not.

[markn]

@HockdogI referenced this same graph as an attachment early in the thread.  The question is "what are the A<B<C curves on plus (+) compared to without plus"?  Similar but firmer, or entirely different?

[jpwhit]

You can calculate what the (+) curves will look like using the ratios in this table between the plus and non-plus. They are going to be wider and a little taller. The asymmetry of the A and C curves are little more pronounced.  

[Mastercrafter]

1 hour ago, jpwhit said:

You can calculate what the (+) curves will look like using the ratios in this table between the plus and non-plus. They are going to be wider and a little taller. The asymmetry of the A and C curves are little more pronounced.  

Maybe the answer is obvious, but if the curve is taller (higher RPM) and longer (duration of increase) wouldn't that give you times that are too fast? What gives in order to counteract the "more responsive feel" of + settings?

[The_MS]

Has to be the Octane 

[Deanoski]

Im just a wally but we ski  4 different SN 196 reg and 6.0 engines  and a 200 with 5.7 ski them all at  A2 

newer  MC 6.0   c-1   

new malibu with the big Moter  A-3

 

we are at 3,000 feet elevation. 

[LeonL]

1 hour ago, Mastercrafter said:

Maybe the answer is obvious, but if the curve is taller (higher RPM) and longer (duration of increase) wouldn't that give you times that are too fast? What gives in order to counteract the "more responsive feel" of + settings?

The chart posted by @Hockdog which was originally published by @scoke (I think) may not be perfectly scaled, but it accurately depicts what happens.  If it were perfect each arc would occupy the exact same area, just shaped differently.  This is required in order to achieve the set speed.  What @Mastercrafter said has to be correct.   If there is more area in the arc there is more speed.  If not, I'd be truly surprised.

[Dano]

My understanding is that it operates on a sine wave.  So if the response is stronger for longer it’s because it has allowed the boat spend more time below the set speed. Which would give it the ability to respond stronger for longer and still keep times.  

[ProStah_Skiah]

32 minutes ago, LeonL said:

What @Mastercrafter said has to be correct.   If there is more area in the arc there is more speed.  If not, I'd be truly surprised.

@LeonL, @Mastercrafter I agree. The areas under the curve need to remain constant (as a basis of comparison across letters/numbers) as ZO only gives back what you take.

Based on this, as a direct comparison to the 'normal' curves, I believe the + curves would all be shifted to the left, peakier and narrower (for a 'normal' skier).

I also believe this is why ZO states that only larger/stronger skiers will benefit from + (they can exert greater forces/load on the boat, which requires a larger area under the curve in response). The curves will only widen/increase duration if you can load the boat to the maximum peak gForce for a given setting.

[Horton]

@Beezer are you sure the tournament boat you are getting is a 6.2 ProStar? This is a somewhat rare boat unless you are at high altitude or the boat is used for Open level jumping. Almost all ProStars are 6.0L

On the other hand almost all new Nautique and Malibu are 6.2. 

Clearly there is some difference between any two different spec boats but but generally the difference between almost any older spec boat and a current spec MasterCraft 6.0L is small. ZO settings make a difference with these boats but it is not radical. Once you get to the 6.2 Nautique or Malibu the difference is much more profound and the correct ZO setting makes a more profound difference. 

The ProStar has a larger prop and has less RPM swing than the Nautique and Malibu. I tend to think as the Malibu as being between the ProStar and the Nautique in terms of feel.

[Horton]

As for Plus, I do not think a softer boat with a Plus setting mimics a stronger boat. I can see where the charts might make it look like it is a good idea but I do not think so. If you carry plenty of speed through apex Plus can feel really good but if you dig a hole at the ball it will abuse you. A super strong boat will abuse your for the same thing but in a different way. The weaker boat with Plus will give you a blip of gas sooner and a stronger boat will provide a even more but typically closer to the wake.

You also have to remember that it adds almost 1 MPH to the boat gate speed. This would be fine if you always ski with plus but if you go back and forth it has to plague your gate timing. 

[dchristman]

@Horton I seem to recall reading Rev S plus mode doesn't add any more gate speed than non-plus. Rev Q and R added extra gate speed for +.