one small reconfirmation on engine cut outs a little when its lean Partially HSN

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newnitro2020

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one small reconfirmation on engine cut outs I had played this video to it's Pacific time stamp I think I almost got what people mean. Affect every time I get excited to think I'm going to know something or something that's going to be fun I got to go to bathroom almost every time. I'm a hyperactive person out and what is it with hyperactivity and going to the bathroom every time. You get butterflies in your stomach and then the next thing you know you got to sit on the toilet I guess it's the thrill and the excitement. Learned so far that what people mean by the high-speed screaming to high RPMs when it's lean is basically when the engine refuses to settle down after applying throttle. I learned that last night now it's just this one piece. And I think I'm good I think I'm not sure. I'm nervous now. For a little over 10 years I'm trying to learn about Nitro and nothing is perfect but I want to know the basics and I think I got it. Just know for those that are looking I'm not trying to be annoying i'm relating to myself and my fellow man obviously. Some things that we may consider annoying could also be things that can surprise us on the other side of things. I learned that but then again I need to practice what I preach. As hyper as I am sometimes. Sometimes I don't have good patience and I could be sort of dXXK. But that's only if I'm inpatient. I Just feel this exciting feeling and now I go to the toilet lol!!!!!!!!!!!!!!!!!!!!!!!!!!

 
Your still too lean if the engine doesn't idle down. Open 1/4 HSN turn until it's gone. It should not sound like it's screaming. Again this comes back knowing factory settings and how far you can go on the HSN to max speed. Usually 1/2 turn tuning is all you have . Such factors :temperature and oil lube will make your tuning window smaller. Never go past maximum speed setting.
 
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a hanging idle is typically caused by too wide idle gap, and too rich on the LSN. think i commented the cause/reasoning behind this on one of your older posts. it can also happen though typically there are other more obvious factors when the HSN is far too lean to where it burned out all of the fuel in the crankcase (typically you will see really bad cutting out or feeling like the engine is falling flat early) so the LSN has to compensate for this. so in that interim after full throttle, there isnt enough fuel in the crankcase so the engine is running lean until the LSN can "catch up" and put enough fuel into the crankcase to stabilize the idle.
the "scream" is usually referred to on the top end at WOT, you can hear the engine above kind of falling flat not really wanting to and having a hard time to "wind up" or "rev up" anymore when he was getting higher in the throttle range, well before the engines capabilities.
its really hard to tell from the video given you dont know what his throttle finger is doing, the LSN could be lean and cutting out, or he could have only pulled the throttle to that point and the engine caught up and stayed there.

honestly what will give you the best understanding is experiencing it yourself. play with tuning a bit then watch most of these videos again, you will be able to get a better understanding of what they mean when they say certain things, or refer to characteristics a certain way.

also it should be noted, it is better to run rich than lean. mostly generally accepted at least. it is much safer and easier to start from a too rich setting and lean out from there. if i know ambient temperatures, humidity, etc are different from the previous time i ran to the current time i am running, i will typically richen at least the HSN by 1/8-1/4 turn just to be sure that i am not going to be running lean. if it changed drastically i will sometimes do the LSN by a few hours as well. it is more dangerous to the engine to start lean and richen it up than it is to start at a known rich setting even if slightly excessively rich.
 
If your talking about when the engine cuts out when he first takes off ,an that big huge puff
of smoke comes out ,then that is where the engine loaded up on idle!

That is where the LSN maybe too rich ,if your engine is too rich on idle ,then the engine will
studder until it clears out!
The engine needs to be leaned a little on the LSN ,the guy is almost there on the tune!
 
a hanging idle is typically caused by too wide idle gap, and too rich on the LSN. think i commented the cause/reasoning behind this on one of your older posts. it can also happen though typically there are other more obvious factors when the HSN is far too lean to where it burned out all of the fuel in the crankcase (typically you will see really bad cutting out or feeling like the engine is falling flat early) so the LSN has to compensate for this. so in that interim after full throttle, there isnt enough fuel in the crankcase so the engine is running lean until the LSN can "catch up" and put enough fuel into the crankcase to stabilize the idle.
the "scream" is usually referred to on the top end at WOT, you can hear the engine above kind of falling flat not really wanting to and having a hard time to "wind up" or "rev up" anymore when he was getting higher in the throttle range, well before the engines capabilities.
its really hard to tell from the video given you dont know what his throttle finger is doing, the LSN could be lean and cutting out, or he could have only pulled the throttle to that point and the engine caught up and stayed there.

honestly what will give you the best understanding is experiencing it yourself. play with tuning a bit then watch most of these videos again, you will be able to get a better understanding of what they mean when they say certain things, or refer to characteristics a certain way.

also it should be noted, it is better to run rich than lean. mostly generally accepted at least. it is much safer and easier to start from a too rich setting and lean out from there. if i know ambient temperatures, humidity, etc are different from the previous time i ran to the current time i am running, i will typically richen at least the HSN by 1/8-1/4 turn just to be sure that i am not going to be running lean. if it changed drastically i will sometimes do the LSN by a few hours as well. it is more dangerous to the engine to start lean and richen it up than it is to start at a known rich setting even if slightly excessively rich.
I understand some of the things you're saying but I'm trying to figure out and turn the sound recognition regarding the high speed in the context of recognize sounds of lean exclusively at the high speed needle. I explain more in the video I just made. The Peace of Mind to know the idea of good sound recognition and see if I was right about one of the scenarios based on this video starting from timestamp 13:54-14:08?
 
Not even close. Still too lean by sound. Get your hearing checked.
 
13:23 "faLLing", not "failing" flat early (capitals make it easier to see the "L", not trying to seem like I'm yelling), almost like it can't rev up anymore even though its not at its peak RPM.

at around 16 minute mark, you kind of got what i was saying i think,
2 strokes, suck air from the carb and bring it into the crankcase, in the crankcase the air and fuel mixes and then gets pulled into the combustion chamber through the vacuum of the exhaust escaping. (this is why it is so important to have a correct pipe with proper back pressure characteristics and that the exhaust gasket is sealing correctly)
so when running lean on the top end (where the HSN is the one in charge of supplying fuel) the fuel and air mixture within the crankcase gets consumed without getting replaced fast enough. and in severe cases, doesn't replenish until you let off the throttle at which point the low speed needle takes over and puts enough fuel into the crankcase and brings the idle speed back down.

***kind of a second part to the above but in reference to the LSN, if the LSN is rich, it will keep loading up the crankcase with fuel as its idling and low throttle 0-25%, so it can also affect the first part of a WOT pass. which is why having a WOT pass is crucial to tuning, as it clears out the excess fuel in the crankcase that might have built up from the LSN, so you are ensuring that you are only tuning to symptoms that are occurring from the high speed needle settings.

16:40 when i was talking about "top end" was referring the peak RPM at the "top end" of the throttle range (80-100% throttle) . pretty much pinned WOT (wide open throttle).

19:20, i am referring to the scream as the sound itself at wide open throttle. sorry i should have put a space right there for clarity, but was kind of in the same thought process, so kept it together.
the sound around 30:42/30:47 or so is a good example of the sound i am meaning. nice and crisp, not really raspy sounding, or "dropping off"

19:58 in the current video, what i was meaning is in the first video around 4:00 minutes in you can hear it start winding up but then it kind of stops "winding up" and building power in the transition between when the engine is at partial throttle and taking off to WOT, then when he takes off wot, it takes off pretty well,
this is the part that i was saying is really hard to judge from the video, as you don't know if that entire time it was pinned/WOT, or if he held the throttle at about 25-50% and then went full throttle when it took off as it should.
and also right at the top end when he is going away and on the way back, it starts to top out on the RPM it stumbles trying to keep building RPM, but stops gaining and not a very crisp sound to it, almost sounds like bouncing off a RPM limiter because its trying to keep building RPMs but can't.

i know i am not the best at explaining things, and hope the above helps and isnt still as clear as mud. i do also want to say many people have different ways of doing things to achieve the same goal as far as tuning goes. "more ways than one to skin a cat" so to speak.
 
I understand some of the things you're saying but I'm trying to figure out and turn the sound recognition regarding the high speed in the context of recognize sounds of lean exclusively at the high speed needle. I explain more in the video I just made. The Peace of Mind to know the idea of good sound recognition and see if I was right about one of the scenarios based on this video starting from timestamp 13:54-14:08?

That video that you showed was a good vid ,the guy has got that tune down pretty good ,I do agree with
what you said on tuning it on a more flat surface though ,but also he probably wanted a little rough to see
how the engine will react on a rougher surface on tuning!
Now ,he did notice he leaned it out a little too much an corrected it ,that sound that you heard was indeed
a sign of a little too lean ,it is when you go full throttle ,there is not enough fuel to the amount of air ratio
when he opens the barrel of the carb wide open ,an also ,the engine will have a chatter sound when
decelerating!
Now ,on the low end ,the idle was 2 staging ,that tells you that it is almost spot on ,2 stage idle is where
the idle drops down twice ,the idle can be tuned for a single stage with a slight adjustment of the LSN
an the idle gap I believe!
But all in all ,the guy did a great job on the tune an your are correct on that it takes everything to watch out for ,
as far as sound an how the engine reacts!
 
That video that you showed was a good vid ,the guy has got that tune down pretty good ,I do agree with
what you said on tuning it on a more flat surface though ,but also he probably wanted a little rough to see
how the engine will react on a rougher surface on tuning!
Now ,he did notice he leaned it out a little too much an corrected it ,that sound that you heard was indeed
a sign of a little too lean ,it is when you go full throttle ,there is not enough fuel to the amount of air ratio
when he opens the barrel of the carb wide open ,an also ,the engine will have a chatter sound when
decelerating!
Now ,on the low end ,the idle was 2 staging ,that tells you that it is almost spot on ,2 stage idle is where
the idle drops down twice ,the idle can be tuned for a single stage with a slight adjustment of the LSN
an the idle gap I believe!
But all in all ,the guy did a great job on the tune an your are correct on that it takes everything to watch out for ,
as far as sound an how the engine reacts!
How you doing? Thank you for confirming that I was right I wanted to make sure and I had that feeling in my mind but I just wasn't sure. Cuz it's just a lot of confusion. You are one of the only people that's all my point. Now disclaimer I'm not trying to discredit nobody else but it's just this guy saw what I was really getting too. it gave me a peace of mind to the point that I know and have an idea of how to speak the language of the high speed. From my experience and struggle and I'm going to do a video talking about how I got into this in the first place as far as my years i've learned that a nitro engine is like people and social interactions and sometimes the weather in life, as well as learning languages from another culture or country. I feel if I could learn this mess that I would have learned so sure action I would have learned a lot of things that I was robbed from. Get personal but it kind of connects with me with my destiny. Thank you very much sir and to everybody who comment and participated in helping me. Force be with you!
 
a hanging idle is typically caused by too wide idle gap, and too rich on the LSN. think i commented the cause/reasoning behind this on one of your older posts. it can also happen though typically there are other more obvious factors when the HSN is far too lean to where it burned out all of the fuel in the crankcase (typically you will see really bad cutting out or feeling like the engine is falling flat early) so the LSN has to compensate for this. so in that interim after full throttle, there isnt enough fuel in the crankcase so the engine is running lean until the LSN can "catch up" and put enough fuel into the crankcase to stabilize the idle.
the "scream" is usually referred to on the top end at WOT, you can hear the engine above kind of falling flat not really wanting to and having a hard time to "wind up" or "rev up" anymore when he was getting higher in the throttle range, well before the engines capabilities.
its really hard to tell from the video given you dont know what his throttle finger is doing, the LSN could be lean and cutting out, or he could have only pulled the throttle to that point and the engine caught up and stayed there.

honestly what will give you the best understanding is experiencing it yourself. play with tuning a bit then watch most of these videos again, you will be able to get a better understanding of what they mean when they say certain things, or refer to characteristics a certain way.

also it should be noted, it is better to run rich than lean. mostly generally accepted at least. it is much safer and easier to start from a too rich setting and lean out from there. if i know ambient temperatures, humidity, etc are different from the previous time i ran to the current time i am running, i will typically richen at least the HSN by 1/8-1/4 turn just to be sure that i am not going to be running lean. if it changed drastically i will sometimes do the LSN by a few hours as well. it is more dangerous to the engine to start lean and richen it up than it is to start at a known rich setting even if slightly excessively rich.
the "scream" is usually referred to on the top end at WOT, you can hear the engine above kind of falling flat" fallen flat when you say basically the engine is struggling to return itself to normal after you let go of the trigger. It goes back to normal? When this happens the engine makes a scream sound a little after you do throttling or let go the trigger. The engine has more air than fuel naked the RPM sound higher than when it's supposed to then can cause the engine to not fall flat in a way that it doesn't either run right on idle or sometimes acceleration depending on weather conditions.


What I'm trying to understand is when the engines screen says just makes a loud sound after as if the idle is Way open or air leak well it's not. That it goes back to regular RPMs at idle. So it produces an unnecessary harmonica scream which is just nothing but air and then the idle runs on in a way that it'll idle regularly but then it will take a while for it to settle. I think I got that right and I'm not sure?
 
the "scream" is usually referred to on the top end at WOT, you can hear the engine above kind of falling flat" fallen flat when you say basically the engine is struggling to return itself to normal after you let go of the trigger. It goes back to normal? When this happens the engine makes a scream sound a little after you do throttling or let go the trigger. The engine has more air than fuel naked the RPM sound higher than when it's supposed to then can cause the engine to not fall flat in a way that it doesn't either run right on idle or sometimes acceleration depending on weather conditions.


What I'm trying to understand is when the engines screen says just makes a loud sound after as if the idle is Way open or air leak well it's not. That it goes back to regular RPMs at idle. So it produces an unnecessary harmonica scream which is just nothing but air and then the idle runs on in a way that it'll idle regularly but then it will take a while for it to settle. I think I got that right and I'm not sure?
while yes the engine is screaming at that point, but typically the term is used under the condition that the engine is being given throttle inputs and at WOT situations.
the symptom of the harmonic scream after throttle that you are talking about is referred to as a "hanging idle", "trailing idle", these indicate an incorrect tune depending on severity and personal preference.
 
while yes the engine is screaming at that point, but typically the term is used under the condition that the engine is being given throttle inputs and at WOT situations.
the symptom of the harmonic scream after throttle that you are talking about is referred to as a "hanging idle", "trailing idle", these indicate an incorrect tune depending on severity and personal preference.
while yes the engine is screaming at that point, but typically the term is used under the condition that the engine is being given throttle inputs and at WOT situations.
the symptom of the harmonic scream after throttle that you are talking about is referred to as a "hanging idle", "trailing idle", these indicate an incorrect tune depending on severity and personal preference.
so it's basically after applying throttle that it makes sort of like a scream sound and then it dies down it can be compared to a hang idle and a sense correct?
 
still too lean. When you do get it; It will be time to buy a new motor and start all over again.
 
so it's basically after applying throttle that it makes sort of like a scream sound and then it dies down it can be compared to a hang idle and a sense correct?
trying to understand and make sure i am understanding your question correctly.
when you say "after applying throttle" are you referring to applying and holding throttle?
or are you referring to the time after applying the throttle and then letting off throttle?
hanging or trailing idle refers to the time after you release the throttle and the RPMs stay elevated *above what idle speed should be and then drops down to an acceptable idle*
*edited for clarity
 
trying to understand and make sure i am understanding your question correctly.
when you say "after applying throttle" are you referring to applying and holding throttle?
or are you referring to the time after applying the throttle and then letting off throttle?
hanging or trailing idle refers to the time after you release the throttle and the RPMs stay elevated *above what idle speed should be and then drops down to an acceptable idle*
*edited for clarity
I'm referring to when you say the engine screams after you let go of the trigger of your controller for instance, not while you're applying throttle. I'm just now confused and I just want someone to explain clearly on everything that happens in terms of this particular condition the other conditions I understand now because I clarified with other threads in with other people before. As well as studying them and other places. I hope you understand what I'm coming from. can you show me some kind of video of what the nitro engine does when it screams????I want the mindset and the piece of mind please please please please please!
 
too lean on high. Starving engine of fuel. Back off HSN 1/4 turn.
 
I'm referring to when you say the engine screams after you let go of the trigger of your controller for instance, not while you're applying throttle. I'm just now confused and I just want someone to explain clearly on everything that happens in terms of this particular condition the other conditions I understand now because I clarified with other threads in with other people before. As well as studying them and other places. I hope you understand what I'm coming from. can you show me some kind of video of what the nitro engine does when it screams????I want the mindset and the piece of mind please please please please please!
32:31-32:32 and again 33:18-33:19 in post #5 (your post) in this string. that is the scream i am talking about, wide open throttle, it is a nice clean crisp sound, it doesn't sound like its stuttering or bouncing off a rev limiter, it doesn't sound raspy.
that is the scream i am talking about.
once he returns you can hear the hanging idle (2 stage idle) then it drops down to its normal idle RPM. this is typical of a rich LSN and idle gap a bit wide.
 
32:31-32:32 and again 33:18-33:19 in post #5 (your post) in this string. that is the scream i am talking about, wide open throttle, it is a nice clean crisp sound, it doesn't sound like its stuttering or bouncing off a rev limiter, it doesn't sound raspy.
that is the scream i am talking about.
once he returns you can hear the hanging idle (2 stage idle) then it drops down to its normal idle RPM. this is typical of a rich LSN and idle gap a bit wide.

I can't even keep track of my own post I can't find post 5, so basically is considered screaming when the engine makes a obnoxious sound that's not normal like stuttering, raspy sound, etc. those are the ways that people say that is screaming in most cases? You can give me a link to post 5 because I cannot find it I'm done so many postings I don't know where to find that?



So the issue and I know doesn't die down is another issue from the screaming part?
 
I can't even keep track of my own post I can't find post 5, so basically is considered screaming when the engine makes a obnoxious sound that's not normal like stuttering, raspy sound, etc. those are the ways that people say that is screaming in most cases? You can give me a link to post 5 because I cannot find it I'm done so many postings I don't know where to find that?



So the issue and I know doesn't die down is another issue from the screaming part?
post identification is on the top right corner of the post:
1615694057176.png


The scream from the engine that i am talking about is the sound when the engine is fully winding up, is NOT stuttering, is NOT raspy sounding, it IS sounding crisp, IS having quick response to throttle inputs.
i am referring to the scream sound DURING and near WOT.
NOT referring to it after letting off throttle during a hanging idle situation.
 
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