which tach should I buy?

[Tyler Davis]

need to buy a digital tachometer to tune my OPE. I opened up the muffler on my 029 Farm Boss and it's running good, but want to make sure it's not too lean/hot. Not sure I'm hearing the four-stoke signature with my ear.
I see $100 tachs and $20 tachs - what's the difference?

 

[sean donato]

Get a tiny tach I've had mine for years, not that I use it much anymore but it's always worked l, can be had off amazon for around $50.00. Cheers mate

 

[Vintage Engine Repairs]

I use the one below made in Japan. The refresh rate is fantastic -
3rd product down. It’s expensive but worth it.

Click on the text, it’s a link to an Aussi site, but you can get them world wide I’m sure.

http://www.hobbysupplies.com.au/Zenoah Acc..htm

 

[Canyon Angler]

I bought a cheapo Chicom jobbie on ebay. Seems to work fine.

 

[drf255]

need to buy a digital tachometer to tune my ***. I opened up the muffler on my 029 Farm Boss and it's running good, but want to make sure it's not too lean/hot. Not sure I'm hearing the four-stoke signature with my ear.
I see $100 tachs and $20 tachs - what's the difference?

Once you modify a saw in anyway, the factory recommended RPM setting goes out the door. Have to tune by ear now. Fatten it up then lay it in and out of wood as you lean it. You’ll get the hang of it.

As for tachs, I personally like a Fasttach. Quick referencing for saws.

 

[lone wolf]

Once you modify a saw in anyway, the factory recommended RPM setting goes out the door. Have to tune by ear now. Fatten it up then lay it in and out of wood as you lean it. You’ll get the hang of it.

As for tachs, I personally like a Fasttach. Quick referencing for saws.

How far from the coil wire will that tach work? My old tach here now has to be right next to it to work.

 

[Tyler Davis]

so are there wired and wireless tachometers? I see some with leads to clip to the spark plug, but I don't want to do that since I want to adjust it with the air filter and cover in place.

Can the wired tachs get an inductive reading without connecting the plug wire?

 

[SteveSr]

I see $100 tachs and $20 tachs - what's the difference?

About $80 LOL! The biggest difference is update rate and replaceable battery (or not). Some of the wired ones will work o.k. wireless as long as you can get it close enough to the spark plug / ignition lead. For the wired ones all you have to do is wrap the wire around the spark plug lead a few times.

 

[sean donato]

I have a photo tach and a tinytach. I like the tiny tach for saws. It's easy to wrap the lead around a plug wire. Clip the top cover back on and have at it. Little harder to do that with the inductive type.

 

[Totembear]

How far from the coil wire will that tach work? My old tach here now has to be right next to it to work.

I put my Fasttach on my handle with a molded holder and it works just fine. Every once in a while it acts up, but its a quick correction. I'd say about 6-7 inch?

 

[lone wolf]

I put my Fasttach on my handle with a molded holder and it works just fine. Every once in a while it acts up, but its a quick correction. I'd say about 6-7 inch?

Thats great. Im gettin one.

 

[drf255]

I bought the Fasttach after a guy walked up to me at a GTG and read my saw rpm from nearly a foot away from the plug.

As Tom said above, there is a seller on the verboten site that sells a 3D printed holder for the fast tach that allows it to clip to the top handle of the saw. I think it’s around $20 and is invaluable. I use it on every new build as a reference. Can also get RPM in the cut for tuning. Then I just pop it off and put it back on my bench for the next build.

 

[dsell]

I have the Electronic Specialties 328 EZ Tach Plus but it has a slow update rate. It's always worked well otherwise.

 

[Okie]

need to buy a digital tachometer to tune my ***. I opened up the muffler on my 029 Farm Boss and it's running good, but want to make sure it's not too lean/hot. Not sure I'm hearing the four-stoke signature with my ear.
I see $100 tachs and $20 tachs - what's the difference?

$100 minus $20 = a difference of $80

I have a Pet 304, think it was also called a Echo. It has a replaceable internal battery. I've never had to open it up to replace the bat.
I very seldom even use a tach now days. I tune by ear for the 4 stroke and use a IR temp gauge to make sure (confirms) the saws block is not overheating when in the cut.

 

[Tyler Davis]

$100 minus $20 = a difference of $80

I have a Pet 304, think it was also called a Echo. It has a replaceable internal battery. I've never had to open it up to replace the bat.
I very seldom even use a tach now days. I tune by ear for the 4 stroke and use a IR temp gauge to make sure (confirms) the saws block is not overheating when in the cut.

I have one of the IR temp guns - where do you measure, and what's the upper limit of "too hot"?

 

[Okie]

I have one of the IR temp guns - where do you measure, and what's the upper limit of "too hot"?

You also say: Not sure I'm hearing the four-stoke signature with my ear.

When I'm using using the IR I have a big log down and aim the IR at the chainsaw's jug while the saw is loaded in a full bar cut with a sharp chain and I want the saw's engine to stay loaded up good in the cut for several seconds, enough for the jug to reach a max stable temp and not exceed 350. If it heads for 350 fast it's going to Over heat. You can do this by yourself with a log down and letting the chainsaw do the cutting W/O forcing the saw if the chain is sharp. I have several post's (not threads that I've started) on this site about such. My searches did not find them. A tach in a full bar cut would have the engine rpm's lower than max spec's with the engine loaded and seem ok, but the engine's block can be overheating when loaded due to number of reasons, but mainly not enough gas hitting the piston (leaning out) and the piston's skirt starts swelling into the cylinder FAST and and producing more heat and eating itself. The OP if not familiar with such will think the saw's chain is bogging down, not realizing it's the piston's friction, lift the saw out of the cut, piss rev's few times and when it picks up throttle rpm's, he jams it back into the cut and starts repeating the act of destroying the saw's piston/cylinder.

Here is some info and a link to tuning by ear by bsnelling that is good.

AND IR temp of chainsaws using a IR theromometer



Nominal OK temp 350F if reached slow in in a full bar cut.

If the temp is rising fast and gets to 375 headed for 400 take it out of the cut and let the engine cool down to 350 or less before killing the saw. Do not kill it when hot or it may continue overheating or won’t cool off fast.



Tuning a chainsaw video by bsnelling.

Very good.

https://www.arboristsite.com/community/threads/chainsaw-tuning-101.250802/