Throttle Curves

[plaster93]

Anyone using them?
I wanna get better mid range on my zdz 80 on a KS 89 can,do you think setting up a slight curve may help the transition? It just seems to sag mid stick,not load up but just hesitates.

[Kiwi]

Plaster,

Absolutely the only way to go to get good linear throttle response. I used it on my 9ZAP and now on my 14MZ. I think it is as critical as setting up aileron differencial.

The good thing is you can put it in a condition so the throttle curve in your 3D or high rate setting is different from your straight line and right hand turn settings.

Do it mate, you will never look back.

Kiwi

[Tailchaser]

Dang Kiwi, care to elaborate on the subject a bit? I too use it but it's kinda of a yeah, that feels kinda good sorta thing.
I think if you would get more into it a bit so we layman can get a better hold on it we would all appreciate it. I know it's a great tool if used correctly,..Thanks.

Chuck<-------------(Never too old to learn a new trick)

[plaster93]

I'm using a 8103 so the throttle curve will be on at all times,no big deal. I guess I'll just have to play with it till it feels right ? The 8103 gives you points to set depending on where your stick is,so you can do either a negitive or positive curve.As the throttle is advanced my positive curve starts to arch at the set points,depending on where I set them,which I guess ins trial and error my mid range throttle should be a little more RPM's than if it were set linear ? Am I right?

[Kiwi]

OK.

You guys owe me a beer if we ever catch up and I will hold you too it.

Heres the deep down secret.

First you set your ATV or end points so you have a good idle with the trim centered. Plus your end point set so your butterfly in the carb is at 90 degrees at full throttle. Dont worry you dont need to get your head inside the fuse to see where its at. Always mark your linkage or bellcranks on the Carby to show fully closed and fully open. Again guys fully open is with the butterfly in a position to provide the least resistance possible to the airflow. Many a time I find them set to go too far and you actually cut off airflow by doing that.

OK we have a good idle. We have absolute full throttle at the high end point.

Now heres the trick. For every click on the throttle ratchet you want a response. I have not counted how many clicks I have, in fact I have no ratchet on my throttle as I want it go where I want it and not to a preset click, so I back off the ratchet and wind in the friction (14MZ here)

Anyway to get back to it without brands. Every click on the throttle should make a smooth change. Given that you can do this on the ground its a breeze. Open up the expo setting and get into changing the curve until no one click on your throttle is the same. There must be a response,

If your radio shows you the curve it may surprise you what it looks like. Often the first 30% is fast to react, then the mid throttle needs a bees hair for each notch, then it goes in reverse and you need to up the servo movement for the last third of the throttle.

On the ZDZ 80 from memory it is a real S curve to get it right, The engine is super sensitive midrange but a turtle in the lower and upper limits.

In the end it comes down to how you like your throttle but I hate a setup that is all midrange and nothing either end. Sure its good for 3D but its a pig for pattern.

Last but not least there is no golden rule. It comes down to what you like but fair dinkum, if you want good throttle response across he range play with the click equals a response setup,

I promise you the beer will taste great and you will be happy to supply a tinnie or two to a poor old bugger like me when you work it out. And even poor old buggers get thirsty.

Kiwi

[plaster93]

Thanks for the info Kiwi, I'll buy ya a six pack of Rolling Rock when I see ya !

[VIPER69]

A good throttle curve is essential.
True story here...last week a guy was wanting me to show him how to do an inverted flat spin. He flies a Katana with a DA50, though not much in the way of 3D with it. I do the flat spin for him and I like to bump the throttle a bit to keep the nose high, and to get out I like to give opposite rudder and end up in an inverted harrier. I have flown Katanas before and they are a breeze to do this with. I am deep into it, and decide the time is right to get out, and .... nothing. I move the throttle a bit more... nothing. I am almost panic mode now. I am a bit cocky and never bothered to check his throttle transition before I took the sticks. So, I am thinking his DA is not liking things and I am thinking of places to set it down quickly when all of the sudden one more click and he is practically at full throttle. Not cool.

Just like Kiwi said, you want a response from every click. I also like the point about possibly going too far for full throttle and actually cutting off some airflow. This is so common, especially with my ZDZ. It will rotate several degrees past wide open that you will end up losing power if you rotate past 90 degrees. Again, I agree with Kiwi, my throttle curve looked like a flat S by the time I was done with it.

As for you foamy guys, you need to find a spot where you can hover and when you set up your throttle curve make that spot pretty flat on either side. I hate it when you give it one click and you climb and one click down you fall. Make that sucker flat in the hover zone so you can play around without worrying all the time and looking like a yo-yo with it.

Good question that too many people overlook.
As soon as my buddy landed we did a quick adjustment on his radio. I could not believe that he was at idle until you hit 75% of the throttle, then .... wham... full speed. No wonder his landings were looking pretty harry. The Katana floats, but not unless you control the power setting properly.

[Tailchaser]

Thanks Kiwi for your reply, and thanks viper for your relevant story regarding this thread.
It's threads like these that help out even the seasoned pilot fly a little smoother.
Is there a particular setting anyone uses just for hovering a 40%er? I know mines a little touchy.And it seems like it should do it without having to play a lot with the throttle, I don't hover much, but it would be nice to be able to do it a little easier.

Chuck

[Pale Rider]

Can any of you guys take a pic of your TX showing the curve?

[Flatlandman]

pale the basic curve i do to start with my da50 setup I use a throtle to throtle mix

and i set the midle number to something lower than 50 to start i use 40 then i fly and i look for equal power. FYI a linear rpm to stick movment isnt what you want a linear power to stick movement is what i want and you can only get that bu fly and adjust

if your using a futaba 9c you just need to plug in a value in the throtle expo for this same effect

[Pale Rider]

Yea I have a 9C also..So when I set the middle point as you described at -40 and all the other points at 0 it looks like a 'V"

[exeter_acres]

Silly question... how are you setting up a throttle curve with a 9C in airplane mode???
I only see the expo setting.. or are you setting it up in Heli mode??