The deception of the pinch test! There is no winning numbers on the pinch test!

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newnitro2020

Gone - bye bye.
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I had been learning within the last 24 hours. this deception of the pinch test method of the nitro engine is overly looked.



For starters there is no such thing as a 3 second count, 4 second count, 5 Second count there is no number in a good pinch test. Originally the pinch test and Counting was to determine how long the engine raises RPMs before it dies.






It works like this if the engine by pinching the line rises up and then drops down right away at the same time as rising up, if it takes 2 seconds at least then you have a good setting.

The key is it's not by counting because if you have a 3 second count let's say and then the RPM might not rise up at all. You're going to be lean even if it lasts 3 seconds. because there was no RPM building up.




Whenever you use the pinch method you must have the RPM rise up and then drop down at the same time as it rises up.

If the RPM rises up but takes a while in a way that doesn't put the engine to sleep or die. Then you're rich.

All it is is in the performance. Some people may experience when the tank is full that the RPM be rise up and then dying within three seconds.

Then if they were to do the same thing if the tank is half empty if the engine take less Than 3 seconds or 4 seconds or whatever, but still has that RPM rising up and drop at the same time as it rises up you have a good low speed needle setting regardless.

Please note!!! even though there is no winning numbers at all. The engine Rises up and die should be at least at 2 second thing. Because one second well by common sense one second isn't enough time for even to rise up, it'll just be enough time for it to die.

 
Nice tip! I had never heard of using the fuel line pinch shut down as a way to gauge your tune. This will keep me busy for a bit, and my neighbors wondering what that noise is!
 
Nice tip! I had never heard of using the fuel line pinch shut down as a way to gauge your tune. This will keep me busy for a bit, and my neighbors wondering what that noise is!
pls let me know how it went???
 
When I pinch mine she just drops the revs slightly then dies, be lucky if it takes 2 secs max!
I suppose some people won’t nip the pipe quite hard enough sometimes and this will give a false reading too?
 

the pinch test deception part 2!!!!​

team losi page on low end!!!!!!!!!
 

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I had been learning within the last 24 hours. this deception of the pinch test method of the nitro engine is overly looked.



For starters there is no such thing as a 3 second count, 4 second count, 5 Second count there is no number in a good pinch test. Originally the pinch test and Counting was to determine how long the engine raises RPMs before it dies.






It works like this if the engine by pinching the line rises up and then drops down right away at the same time as rising up, if it takes 2 seconds at least then you have a good setting.

The key is it's not by counting because if you have a 3 second count let's say and then the RPM might not rise up at all. You're going to be lean even if it lasts 3 seconds. because there was no RPM building up.




Whenever you use the pinch method you must have the RPM rise up and then drop down at the same time as it rises up.

If the RPM rises up but takes a while in a way that doesn't put the engine to sleep or die. Then you're rich.

All it is is in the performance. Some people may experience when the tank is full that the RPM be rise up and then dying within three seconds.

Then if they were to do the same thing if the tank is half empty if the engine take less Than 3 seconds or 4 seconds or whatever, but still has that RPM rising up and drop at the same time as it rises up you have a good low speed needle setting regardless.

Please note!!! even though there is no winning numbers at all. The engine Rises up and die should be at least at 2 second thing. Because one second well by common sense one second isn't enough time for even to rise up, it'll just be enough time for it to die.

What the pinch test tells someone is the longer the engine runs after the pinch tells you in a ball park area just how rich the engine is running.

Ideally you want the engine to rev up slightly then die. Not fall off or rev down.

Revving down would indicate a too rich setting. Bogging down is the term.

Revving up slightly as the fuel is burned out then dieing is optimum.

Revving up more than a few hundred RPM would indicate a lean setting. The few hundred RPM is for ringed sport, side exhaust engines with bushings.

With today's high performance high rpm engines, I like around 500 extra RPM for about 2 seconds then die. This tells me I have the correct fuel to air to the last combustion. Not bogging down slowly rich or screaming lean to the end, just rev up and die.

But what do I know I never blew out a plug in 40 years.
 
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