ear adjustments

[Greg]

Do any of you make carb adjmnts strictly by the sound, or do you always use a tach? Check out Madsens1.com, they have great info about sharpening a chain and tuning a saw with audio files to let you hear how it should sound, they also have some great logging pic's. Doesn't help me much, I have the saw shop guys adj my saws with a tach, but still a great web site.
Greg

 

[John in MA]

Heck, I don't even own a tach. I'm going to buy one soon, but I've just used my ear for a long time. Seems to work well enough for me.

 

[eyolf]

I used my ear for forever...I looked for peak rpm on the high speed, then richened up just a mite until I could hear the rpm's drop a bit. All based upon the idea that an engine under load wants a slightly richer mix for best power and the principle that a 2 stroke depends on fuel mix for some of the cooling.

After being here for a while, I decided to try using a tach...that, and running onto an old electronic tach at an auction sale...I learned that I was consistently running just a bit too rich.

And burned up one of my saws.

I should mention that the saw was an older one with many hrs on it, and that I had been using hard on a hot day...


Final word is that the tach I got for $8 at an auction has failed. Anybody got a favorite model to choose as a replacement if I decide to get a new one?

 

[crowe]

I use to always tune by ear but the more serious I got about saws the more I wanted a tach just to see how close I was. I was pretty close but seemed to be abit on the rich side myself. The bottom line is that a person should know what sounds right and what doesnt but it is nice to have one just for reassurance sake. I bought one about 2 yrs ago off Madsens it is a stihl and I paid about 130.00 dollars for it. It is pretty neat how it works the battery life on it is incredible and it only activates when you hold it over the saw to tune it. It comes with a wire and snap clamp that you can hook up to the saw for fine tuning, however I just hold mine over the saw and it works great. Buy it fo peace of mind if nothing else. Take care Wade Huggins

 

[tony marks]

what eyewolf said about cutting back just a little at pk ,has worked for me. i have a 20 command kohler,that dont sound good at all no ld . but i double blade and when i engage blades she will turn 3860 . an loves it. incidentally with single blades she only gets 3750.
this indicates to me that she is really only working optimum under load.i break a few belts but when i need it i can ask for about as much as ive seen any 20 hp of anykind ,put out
know its not 2 cycle but seems the principle idea still applys.

 

[Methoss084]

I'd say that a tach works great on 4 strokes for getting optimum blade speed or implement speed on a peice of power equipment. But eyolf has it pinned, on most saws its best to adjust to peak then richen it up just a bit. This is how we tune all our customers saws. I guess that some of the racers would disagree, and prefer to use a tach for max. RPM's.

Tony, what machine is your CH or CV 20 on? You should only be turning 3600 at WOT without the PTO engaged.