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that sucks......

ill keep my ear to the ground.......I know where there is a few 2100's :hmm3grin2orange:

I know where there is one or two 2100's, a 394 and one or two of something else Husky about a k from here, but the old bugger won't part with them even though he will never do anything with them (in need of repair)!
:dizzy:
 
Forgive me for being an obsessive tuner, but the carb issue on work saws is still bugging me - and after reading all the tricks on EC Birts forum, I feel there has to be more in it for a work saw.

The analogy I make is that a race saw is set up for the sweet spot in porting - kind of like setting up a dragster. Whereas a work saw is more like setting up the jetting on an enduro bike.

When you are cookie cutting, you try and keep the saw in the sweet spot - it seems that almost any carb can be set up to work within that narrow range. I've seen some bored out carbs for racers that I know would never meter well on a work saw.

However, the varying conditions of a work saw demand a broader range of good metering (like the enduro bike). I noticed the last time I was cutting that if I opened up the high speed needle another 1/8 turn that it seemed like I could pull the saw down below peak torque and not have as great a problem with bogging. I also noticed that it knocked some power off my peak horsepower.

All this is largely a subjective feel. If I had a tach installed on the saw I would be able to monitor and document the rpm levels to confirm the spread of power and where it bogged.

I just may have to get a tach to mount on the saw and a pop off guage (and a bunch of springs and shims). I could start out with one high speed setting on a log and document where the power was, then tweak it a bit and see how that changed the spread of power. Then, try a different pop off pressure and re-test.

My gut feeling is that a slight drop in pop off pressure along with a slight leaning of the high speed needle would give me broader and more forgiving powerband - just what I want for a work saw.

Matt, do you have any more of those tachs?

Work saw or race saw this is what you aim for, the sweet spot of where you are getting the best performance, with both torque and horsepower, Peak revs mean nothing and honestly if you are setting your tuning to where you are getting a good fourstroke that cleans out nicely in the cut you are as close as you can physically get, unless you get really envolved and start going to computers operating every aspect of fuel metering, exhaust gas monitoring etc. with a saw there are a lot of variables including the way you have sharpened the chain which is where you will find your biggest gains. Today I was running my 660 with a new carlton skip chain on a 42 inch bar and could dig the spikes in as hard as I would like spraying chips as far as any saw is capable and could not bog it but I put my 25 inch bar on the same saw with a chain I had sharpened to my specs and it cuts FAST but I could bog it easily if I tried.I generally try to run a little on the rich side so that things run cooler, but I think that you are trying to overthink the tuning thing a bit too much.

If you feel that you need more saw power....Buy a bigger one!
 
And this is for Trav and Andrew. :D

Unfortunately it won't work on Randy, he's already seen it and guessed what I had in mind :laugh:

It's courtesy of our current Australian Open Chainsaw Champion (overall pointscore)

Cheers lumberjackau !

attachment.php

I thought that was settled when mcBob got envolved and basically admitted that it isn't the saw so much as the driver. chainsaw races mean JACK snot in the real world anyway!

Had my 660 singing today, could hear the couple of huskies in the distance struggling their butts off, bogging in logs half the size of what I was cutting!
 
Rick, I read the article. I did find some interesting information, especially on the relationship of the area of the diaphragm to the diameter of the metering needle orifice. I did agree with what he said about the high and low speed screws being the most important adjustments, but that's a, like Duh, I don't think anyone would disagree with that statement.

I kept waiting to get to the good stuff, then he wrote "I will have more to say about the hype and misunderstandings surrounding pop-off pressure and metering lever adjustments shortly." - You beauty, getting to the guts of the inquiry.

I then arrived at the end of the article without one further word about pop-off pressure or metering lever adjustments. - Bummer, I felt ripped off.

I have been through numerous threads on EC Birt's forum where certain recommendations were made about changing their pop-off pressure and changing the metering lever adjustment - and the replies were like "thanks, that fixed it!" yada, yada.

Here is a link to the forum, check out the Tillotson forum for lots of questions and replies -
http://www.eccarburetors.com/forum.html

I'm getting the impression if I want to get to the bottom of this, I'm going to have to do my own testing.
 
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I thought that was settled when mcBob got envolved and basically admitted that it isn't the saw so much as the driver. chainsaw races mean JACK snot in the real world anyway!

Had my 660 singing today, could hear the couple of huskies in the distance struggling their butts off, bogging in logs half the size of what I was cutting!


Sounds like stihls may have improved. What I remember is that they were overweight, overpriced and underpowered.
 
Rick, I read the article. I did find some interesting information, especially on the relationship of the area of the diaphragm to the diameter of the metering needle orifice. I did agree with what he said about the high and low speed screws being the most important adjustments, but that's a, like Duh, I don't think anyone would disagree with that statement.

I kept waiting to get to the good stuff, then he wrote "I will have more to say about the hype and misunderstandings surrounding pop-off pressure and metering lever adjustments shortly." - You beauty, getting to the guts of the inquiry.

I then arrived at the end of the article without one further word about pop-off pressure or metering lever adjustments. - Bummer, I felt ripped off.

I have been through numerous threads on EC Birt's forum where certain recommendations were made about changing their pop-off pressure and changing the metering lever adjustment - and the replies were like "thanks, that fixed it!" yada, yada.

I'll get a link in just a sec.

Terry looking at Karts and saws is like looking at apples and oranges, Karts need a wider torque and power band because they need to slow down and then accelerate out of corners, a chainsaw is simply running at WOT from the moment it hits the log till the time you come out the other side, and it comes down to the skill of the operator to keep the load up to the saw and sharpen the chains correctly!

As I said earlier How you sharpen will make a far bigger difference than fiddling the carby!
 
Sounds like stihls may have improved. What I remember is that they were overweight, overpriced and underpowered.

Lighter cheaper and higher powered, and more reliable don't you mean? I can buy a big stihl cheaper than a husky that even comes near the same performance levels! oh and much lighter than the no longer available macs in the size range!

sorry randy but you did leave yourself open to that one!
 
Lighter cheaper and higher powered, and more reliable don't you mean? I can buy a big stihl cheaper than a husky that even comes near the same performance levels! oh and much lighter than the no longer available macs in the size range!

sorry randy but you did leave yourself open to that one!

Nah, I meant exactly what I said. The most disappointing was the 075, a porky, bulky thing that couldn't pull a 48" in very soft wood.
They weren't all horrible, the 031 was a decent little saw.
 
Mate, I know how to make a sharp chain and to set the cutting angle to the job I want to do. Like I said, I am an obsessive tuner, that's why my bikes, cars and trucks are always top performers.

You may not be interested in carburetion issues, but I am. I have built my own jets, turned my own needles and altered slides to my own dimensions. My bikes ran clean and strong no matter what the situation.

I see the potential for better carburetion on saws, but I don't see a lot of information on the issue.

Buy a bigger saw? Why not buy a different carb? - I think you got me mixed up with someone from the 'consumer society' - I like to roll my own.
 
I think you have a point Terry, saw carbs seem crude and haven't progressed much. Sure they are more complicated, due to EPA stuff, but have they improved?
 
Randy, as already mentioned, the guys that run karts are taking the same carbs and getting them to pull off the line from dead starts, accelerate out of turns and wind out down the straights.

Crikey, if they are using the same carbs to do those different jobs, why can't a tuner tweak his chainsaw carb to give it a bit broader powerband. It might not cut cookies any faster, but it may be a more fun saw to use when doing real work.
 
Rick, I read the article. I did find some interesting information, especially on the relationship of the area of the diaphragm to the diameter of the metering needle orifice. I did agree with what he said about the high and low speed screws being the most important adjustments, but that's a, like Duh, I don't think anyone would disagree with that statement.

[snip]

I'm getting the impression if I want to get to the bottom of this, I'm going to have to do my own testing.


Terry, it's like anything, there are often nuggets but you have to discard a lot of potch to get there., it just looked there were some interesting things/hadn't read it that way before, like you said.
 
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