Cutting with saw using less than full throttle

[SawTroll]

You are right here, but I dont need the sawing at max torque all the time.
I should say that reading last days these threads about throtling I´m now in the forest wery nervous and stressed. All the time something is bubling under the hat, is the mix normal or lean

Don't worry, just cut!

At full trottle, that is ! :blob5:

 

[jokers]

:Eye:
Give the values

I did give the value, or do you want a specific value for your saw?

.......bore is not max too at half throtle......

huh?????

so air speed and vacuum can be the same

Related, yes. Sufficient to fully enable the hi speed fuel circuit? Prove it.

Russ

 

[pinus]

I did give the value, or do you want a specific value for your saw?



huh?????


Related, yes. Sufficient to fully enable to hi speed fuel circuit? Prove it.

Russ

Give for the saw for what you surely know it
Actually the difference should not be large, IMO some 15-20%. This is not spiker for you

 

[jokers]

Give for the saw for what you surely know it
Actually the difference should not be large, IMO some 15-20%. This is not spiker for you

I`m sorry pinus, you`ve got me laughing, but I have no idea what you are saying to me.

I`m assuming that you are saying that the delta in the stoich ratio is no more than 15-20% between running at full throttle and mid throttle? No, I don`t know this, do you? Have you got a verifiable referrence? Can you guarantee this to be true under all(or even most) circumstances and atmospheric conditions?

My concern with partial throttle operation is based on empirical evidence of significantly higher than normal lean seizures of saws operated at partial throttle.

Russ

 

[pinus]

I`m sorry pinus, you`ve got me laughing, but I have no idea what you are saying to me.

I`m assuming that you are saying that the delta in the stoich ratio is no more than 15-20% between running at full throttle and mid throttle? No, I don`t know this, do you? Have you got a verifiable referrence? Can you guarantee this to be true under all(or even most) circumstances and atmospheric conditions?

My concern with partial throttle operation is based on empirical evidence of significantly higher than normal lean seizures of saws operated at partial throttle.

Russ

Laughing...thats is good news
Russ, as I see you is tryng to say more than you actually know

 

[SawTroll]

....... My concern with partial throttle operation is based on empirical evidence of significantly higher than normal lean seizures of saws operated at partial throttle. ...

That is good enough reason for me, considering that my cutting needs doesn't call for the use of partial trottle anyway..... :angel:

 

[jokers]

Laughing...thats is good news
Russ, as I see you is tryng to say more than you actually know

That`s OK pinus, state what you know. Even though "I`m a know it all", I don`t know everything yet.

I`m serious though, if you have knowledge or legitimate evidence to refute my belief that partial throttle operation is not a legitimate mode of operation for a saw, bring it forth. I share plenty of what I "know", how about some from you rather than a statement along the lines of "I think......."?

Russ

 

[spacemule]

I know the derivative for the stoich function is atmospheric plus 6 lbs. mixed with two cans of beer and a pint of horse piss quantity squared.

 

[jokers]

I know the derivative for the stoich function is atmospheric plus 6 lbs. mixed with two cans of beer and a pint of horse piss quantity squared.

You have finally revealed your hand, you must be a Stihl engineer!

Russ

 

[spacemule]

Ha ha. Yeah, don't tell anyone, but Stihl only uses Clydesdale piss. You know what they say, "Only the best for the loggers!"

 

[rbtree]

Good on ya 'mule, for scientifically settling the debate.

Question for ya, Russ. Let's say you have a rookie operating a saw, limbing perhaps, but regardless of the wood size, he is running the saw very near its top rpm, meaning improperly. If the saw had a carb (like most saw carbs, you guys say), that shouldn't be run at partial throttle, which would be worse for the saw, running at WOT, rather than within the optimum power band, or running at partial throttle. Could the saw be in a lean condition? Or should I simply run a test and check plug color afterwards?

My guess is, the best way to make a saw last, especially if multiple operators are involved, would be to adjust them a bit rich.

 

[bnew]

I agree with neverenough and jokers. Im no chain saw guru but have moded a few of my 2 stroke atv's to the hilt.WOT under a load will give a richer condition and when letting off, let off. Dont slowly ease off the throttle, it will lean up.MY theory is that the metering rod will cut the fuel flow faster the the venturi vacuum causing a lean condition.The last part might be BS,Hell it might all be BS but thats my story and Im stikin to it.

 

[rbtree]

Good thread, guys. Thanks for the help, and technical info on the inner workings of carbs. Guess I've never fully comprehended them till now.

 

[bnew]

The plug idea is good if its a brand new plug. Warm the saw up with the old plug. Change the plug.Run the saw hard in wood for a less than a mimute and check the color to above mentioned.

 

[weimedog]

Plug check if your nervous. NO carb is perfect at all RPM's. They just have to be good enough not to either toast the barrel because of lean condistions or run to rich. I run part throttle where it makes sense. Often. I also have plug checked my saws often to get them running nice and brown-tan on the plugs. I think this is a non-issue for most.

 

[pinus]

The plug check seems being a good trick
For my saw it is interesting that half of the plug isolator is rather light brown another half blacky, so