To those who like the Intellicarb...

[Dennis]

I just caught back up on this thread again...once again...I find it hard to believe that this is caused by an airleak...I pressure tested it myself, as I do all my saws...(I guess I cannot account for an oil seal failure after running or anything to that aspect)...This particular saw also ran perfectly for numerous cuts by myself, Gypo, and Rotax....while it didnt keep up to the 046 of Roberts...it cut very well...possibly a bit on the rich side, which is what I had told Russ about. I am very curious to find out what is happening as well...I have to build another 260 pro shortly...and I think I will recommend buying the adjustable carb.

 

[WRW]

Ben,
http://www.maximausa.com/technical/oilratio.html
"Jetting: Increasing oil (per gallon of gas) may require increasing jet sizes. Decreasing oil (per gallon of gas) may require reducing jet sizes"

 

[bwalker]

WRW, Yes a richer oil mixture MAY require rejetting, but as I have mentioned before the differance between 50:1 and 32:1 is 1%. could it have a effect? Yes. Is it making a big enough differance in this case? No, I do not think so. FWIW My saw went from a 52(i think) jet to a 58 before it ran OK. There is no way in he ll thata 1% differance in oil concentration would account for this.

BTW this is a quote from the maxima link you posted: "Small displacement, high-RPM racing engines should use rations no higher than 32:1."
They are referring to 60-125cc liquid cooled bike mototrs. Saws rev higher, run hotter, and are subjected to more load. Can you see why its a good idea to run a quality oil 32:1 ratio now?

 

[WRW]

Ben,
I thought we had already established that chainsaws were not considered to be high performance engines, hence the room for improvement. The wording is, "Small displacement, high-RPM racing engines should use rations no higher than 32:1." I place My emphasis on the word "racing".
My point was, origionally, that 32:1 is not recommended by the manufacturer and as such is not stock. Your oil manufacturer states that richer oil concentrations may require larger jets, so it is not to be unexpected if you do have to re-jet when using a higher concentration mix.

 

[bwalker]

Bill, My point was that the big differance in jet size mine required would not be justfied by a slight change in oil mixture.

You think these little saws are not as stressed as a bike? They are stressed WAY more. Run way hotter, at way more RPM. While saws are not high performance as far as HP per cc goes they neverthe less strain a lubricant much more than liguid cooled bike.

 

[WRW]

Ben,
What is that...a 36% increase of oil? I honestly don't know how that should affect jet size. I am willing to believe, based on your experience, that there should be some increase in jet size.
Saws run on load and then get a break. Except for short periods of braking, racing bikes run at full load throughout the race.
Back to the initial post, I'm none too happy with the thought of a non-adjustable carb. A friend has one, and his mech had a time with it, all the while he couldn't use it. If I'm reading these posts right, Stihl may be backing off from using them.

 

[Tzed250]

stress

Actually, a 125 motocross or roadrace engine is stressed much more than a saw, if you cosider stress to be HP output vs. power unit weight. A 125 bike engine puts out double the HP of a similiar sized saw and is used "under load" at much higher RPM. 50:1 vs. 32:1 has very little effect on jetting. Gordon Jennings did experiments with oil mix ratio back in the '70s and found that and found that the power level produced at 16:1 was nearly the same as 50:1. This of course with the jetting set ot provide the correct mixture for each ratio. The EPA is worthless. I saw them run two-stroke roadbikes out of the country in the 1980's and now they have screwed up saws, both of which don't amount to a hill of beans as far as emissions are concerned.

 

[Fish]

Well now I am getting real pissed, and about ready to leave,
unless you all talk me out of it!!!

I have'nt read all of the useless crap posted since my last post,
as it is hard to read, but I can tell, I am mad!!!

I have been polishing my jets for a few months, and I can see
that any real discussion of the intellicarb, or the stupicarb,
will be buried in a tidal wave of bullsh&t. But I digress.

The reality likely is that Stihl is following EPA guidelines, as is
Echo, but since E-lux has a huge bank of already made
carbs, and they can use them until they run out, that may take
a decade or two. The legal finer points may not be covered
here, but why would Stihl do unpopular things unless they had
to?

That is why the old Briggs pushmowers are still being sold, as they hqve been already made for a while.

Not trying to start trouble, but just trying to inject a little reality.

 

[bwalker]

What is that...a 36% increase of oil? I honestly don't know how that should affect jet size. I am willing to believe, based on your experience, that there should be some increase in jet size.

It might be a 36% increase in oil, but jets meter by viscosity so the change is very slight. I have noticed a slight change when going from 40:1 to 20:1 in my street bike, but it wasnt a whole mainjet size.

Saws run on load and then get a break. Except for short periods of braking, racing bikes run at full load throughout the race.

Roadrace machines yes, MX bikes no. they are constantly on and off the throttle.

Actually, a 125 motocross or roadrace engine is stressed much more than a saw, if you cosider stress to be HP output vs. power unit weight. A 125 bike engine puts out double the HP of a similiar sized saw and is used "under load" at much higher

Tz, I was talking mostly about thermal loads dues to air cooling. However I wouldnt say the load a saw sees is much less than a mx bike.Mx bikes are never loaded that heavily because of traction issues. Roadracers are another story all together. They are very highly loaded because of perfect traction and sustained high rpm's.

Gordon Jennings did experiments with oil mix ratio back in the '70s and found that and found that the power level produced at 16:1 was nearly the same as 50:1.

Didnt the test he did and a later one by AG Bell indicate a increase in hp with more oil? Mac authored a sae paper that came to the same conclusion.

The EPA is worthless. I saw them run two-stroke roadbikes out of the country in the 1980

Isnt thast the truth. I love my rz 350. I cant imagine what a rz500 in a modern chassis would be like.

 

[WRW]

Fish,
Are you saying that E-lux bought bought out Mac's for their carburetor supply? Is there nothing Stihl can do?
Don't go away........... mad.


Bill/Shut

 

[Fish]

So you want me to go away!?!!!


Who said anything about McColluchs? I didn't read any of the
jiberish between my post and yours.

When a new law or ruling comes down, it does not apply to the
product that has already been manufactured, so the parties
concerned can sell off the existing inventory.

Stihl has been getting a bum rap here lately, and Echo and
Shindaiwa have gotten little or no credit for being ahead of
the curve. Just because Elux has a huge warehouse of old,
adjustable carbs, does not mean that they are the best.
But I digress.......

 

[glens]

<b>Ben</b>:&nbsp; I remember when the RZ350's came out after the two-stroke dry spell.&nbsp; Most of the first year run wound up getting wadded up because all the little kiddies weren't used to a bike not decelerating when they chopped the throttle.

<b>Fish</b>:&nbsp; The same thing happened with high-capacity magazines being purposely manufactured in massive quantities before the deadline.&nbsp; Even though they've been banned for what, 6 years or so now, they're still readily available since they were grandfathered.

Yes, there's a lot of BS in this thread.

Glen

 

[Dennis]

Fully adjustable Intellicarb?

Stihlman036...after rereading this whole thread again....I see you made mention of the intellicarb having the capabilities of being fully adjustable...How do you go about doing that.....I realise you would change the top plate with that breather hose...but would you just drill and tap the high adjustment hole...then put a solid jet in the carb...??? this was the first intellicarb I have dealt with...

 

[ccicora]

Dennis, First off thanks for a pratical question

Ok what I have been doing with the intelecarbs is this. Keep the top plate. Find an old fully ajustible carb and put the new top plate on the old carb. But I also usally do a full carb job using the newer gaskets from the new carb or get a carb kit.

I have noticed with very little twiking to the carb it handles a modded 026 very well. My 026ProCC easily is out cutting my 036pro. I do have a stock 026 Pro also that has the fixed jet and runs fine. You just need to realize the limitation of the equipment...... Then Mod them

Dennis, Thanks again for asking

Chris

 

[alamo-kid]

intellicarb

I have a ms 260 that came with a fully adjustable carb that has the intellicarb feature ( walbro wt-581 222 ). It seems that some are still confused on this topic. Intellicarb has nothing to do with the high or low speed adjustments.

I have an 026 that came with no high speed adjustment screw "fixed jet" and no intellicarb feature (walbro wt-403b) and as I said the ms 260 that has intellicarb and a high speed adjustment screw "non fixed jet". Therefore they are not one in the same.

The "fixed jet" carbs I have observed have the high speed adjustment needle location bored over size and then plugged therefore it cannot be "tapped out" and made adjustable.
I think the fixed jet carb is a "POS" and I am in the process of replacing it with a fully adjustable one but It's really pretty simple, if you have a fixed jet carb and can't "live with it" then "replace it". Sure it sucks to spend money to correct something that shouln't have been but it could be worse... what if there was no fully adjustable replacment for all those "POS"
fixed jet carbs.

jeff

 

[Kneejerk Bombas]

Kinda like the restricted muffler, hey?
Why is Stihl forcing this things down our throats? No other saw maker is dealing with emissions. Husky will never do this.
I will only buy Poulan, from now on.

 

[glens]

Jeff,

I'd given a link earlier in the thread to http://wem.walbro.com/walbro/category.asp?GroupName=Chain+Saw&FamilyName=STIHL where they show a needle behind that cap (which is shown to be the idle circuit), or so it would seem.&nbsp; What do you make of that?&nbsp; I don't have any fixed-jet saw carbs to inspect, so I'd appreciate the feedback.

Glen

 

[Dennis]

Chris...lol...ok...I get it...but once again, we are still stuck with using(and finding or buying) the adjustable body...so we need a second carb. That annoys me to be honest....this saw is the first one I have seen with this feature...Are Intellicarbs available fully adjustable on any stock (Stihl) saw??..Limiter caps are easier to deal with....lol...And yep...Modify everything!

 

[bwalker]

Are Intellicarbs available fully adjustable on any stock (Stihl) saw??..Limiter caps are easier to deal with....lol...And yep...Modify everything!

All the stihls with the IC I have seen except the 260 are adjustable.

 

[Dennis]

Ben...Ok, that makes more sense now...because I don't remember seeing the non adjustable on any of the other Stihls...not that I see too many "new" Stihls..most of the ones I get for mods are a bit older....

I have an 020 Super that I am finishing up today...I have to say that I like the way its built. A bit tricky to tear down if you have never done one before...but I like the saw itself...should have some before/after times today sometime...oh yeah...no intellicarb...lol