What exactly is 4 stroking??

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What is going on inside the saw to make it produce this unique sound???

Also, I have not attempted to try tuning my own yet, because I have difficulty distinguishing this sound. I've listened to the Madsen's link and it's still not very clear to me are there any vids available to compare the 4 stroking sound to one that is running lean???
 
I am on the forum chitlist now, so many will hop in and disagree, and I have
gone over this thing many times before, so if this thread turns ugly, don't
take it personal.

When adjusting a good running saw, I repeat, a good running saw.....

In the past, both needles would be started at 1 turn out each.

Which means, turning the high and low in until they seat lightly, and backing
them out 1 full turn to the left..
I suggest 1 and a half turns each to start.
See if the unit will run, if it will, see if it will still run without "goosing" it.
If it won't, turn the low speed screw counter=clockwise and see if it will
idle.
On all of these units, the low speed screw is closest to the engine.

At roughly these settings, the saw should run. Yhe low speed screw should be turned clockwise, and the idle speed control down so that the chain will not turn at idle.

Then when "revved" the response should be "crisp", and immediate,
not bog.
If it bogs, and turning left of both screws does not help, then you have
more work to do.

That is as in depth as I can get here, I am sure my enemies can explain it better.
 
if a 2 stroke has a power stroke very time the piston reaches top dead or there abouts then logic wood have it 4-stroking wood be a misfire every other turn such as a 4 stroke with valves does.(the ex stroke not missing)
some exhaust gasses are pulled back into the intake mixture which displaces some available oxygen causing a mis fire when not under load.The slightly rich mixture causes this and will be correct when under load.
someone will correct me if this is wrong
 
I am on the forum chitlist now, so many will hop in and disagree, and I have
gone over this thing many times before, so if this thread turns ugly, don't
take it personal.

When adjusting a good running saw, I repeat, a good running saw.....

In the past, both needles would be started at 1 turn out each.

Which means, turning the high and low in until they seat lightly, and backing
them out 1 full turn to the left..
I suggest 1 and a half turns each to start.
See if the unit will run, if it will, see if it will still run without "goosing" it.
If it won't, turn the low speed screw counter=clockwise and see if it will
idle.
On all of these units, the low speed screw is closest to the engine.

At roughly these settings, the saw should run. Yhe low speed screw should be turned clockwise, and the idle speed control down so that the chain will not turn at idle.

Then when "revved" the response should be "crisp", and immediate,
not bog.
If it bogs, and turning left of both screws does not help, then you have
more work to do.

That is as in depth as I can get here, I am sure my enemies can explain it better.

Chitlist my ass. Good post.
 
Wow, stepped right up, eh?

Have you ever helped anyone here? I haven't.........

Sorry, my lash out program is hitting hard, I am on full defense mode.

My grandmother has me on her "hate" list right now, she thought I had somethging to do with Oswald, ...........

I love you man......
 
I am still trying to digest my last batch of hate posts, which I get a lot of.

So I am on the defensive a bit, so I apologize for my "snippy" behavior.....
 
What is going on inside the saw to make it produce this unique sound???

Also, I have not attempted to try tuning my own yet, because I have difficulty distinguishing this sound. I've listened to the Madsen's link and it's still not very clear to me are there any vids available to compare the 4 stroking sound to one that is running lean???

I'll try my best with words (iffy at best!). A saw that sounds lean will have a very even sound at wide open throttle- no breaking. A properly tuned saw will have a little bit of a burble, i.e. the pitch of the sound will periodically break.
I hope that helps. When I show new guys, I have them hold the saw at WOT, while I adjust the hi-jet, this seems to work - give it a shot. I bet someone else can put it into better words than I have if none of this makes any sense! - good luck - Sam
 
Once you get done messing with the low speed and idle settings, you can then adjust the high speed. Make some radical adjustments just to hear the different sounds.At full throttle turn the high speed jet counterclockwise enough to hear the saw bog down and sound like it's power is going away and running rough, then go clockwise slowly and hear the saw start to clear up and then it will come to a high rev stage with no roughness....you have leaned it out too much at that point......go back counter clockwise until you here the rough running start to come back.....at that point it is "4 stroking".

Keep in mind you don't want to stand there for 5 minutes playing with the high speed jet at full throttle, at that point not knowing what 4 stroking is will be the least of your worries. Just a few seconds to actually screw the jet in and out won't destroy a saw so play around with it, it's how I finally learned.

The next phaes will be you wanting a tach to see where you are at with max rpm's!

If your carb screws have limiter caps, I don't know what to tell you as they really hinder ear tuning.
 
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I am still trying to digest my last batch of hate posts, which I get a lot of.

So I am on the defensive a bit, so I apologize for my "snippy" behavior.....

Hahahaha!:cheers:
It's pretty intimidating to do carb adj. for the first time. It's really quite easy if you follow the given instructions.
Don't worry about blowing it up as you'd have to super lean it out to do that.
I've seen saws that were never adj their whole life and were quite carboned up and when adjusted to specs they blew up because the carbon got so hot.
Gypo
 
I am still trying to digest my last batch of hate posts, which I get a lot of.

So I am on the defensive a bit, so I apologize for my "snippy" behavior.....

I guess I was wrong...sounds like an enema might do you good!
 
Thanks for the help folks. This is a new 357xp that I've had prolly 15 tanks through. I think it's running a bit on the rich side,since I think it's 4 stroking good. I'm just a bit paranoid about playing with the carb settings on my beloved Husky till I get a bit more experience. I may play it safe and get someone with a bit more experiance to show me the ropes first hand.
 
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What is the advantage of 4 stroking? ? Or is this just tuning up the saw? Sorry trying to comprehend all this in my head
you have to forgive me as I am learning also..

Fish good to see you back in form!!!:laugh:
 
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