Tuning question

[JasonRKBA]

Question for the pros. I've always tuned by ear and my saws have ran well. I have placed a tach on a couple and see that they are running around 1500rpm less than the stihl manual suggests as max rpm not under load. While trying to increase the rpm using the tach it feels as I may be pushing a little to hard. And both that I've done this with sorta pulsed it the top end. Is this just par for the coarse? Or should I back them off as they where.

Thanks. Jason.

 

[Clemsonfor]

Question for the pros. I've always tuned by ear and my saws have ran well. I have placed a tach on a couple and see that they are running around 1500rpm less than the stihl manual suggests as max rpm not under load. While trying to increase the rpm using the tach it feels as I may be pushing a little to hard. And both that I've done this with sorta pulsed it the top end. Is this just par for the coarse? Or should I back them off as they where.

Thanks. Jason.

I know I'm no help, but some swear by the tach and set it at the published limit.

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[Deets066]

By pulsing do you mean 4 stroking or stuttering?
If stuttering then they are too lean

 

[WKEND LUMBERJAK]

How fast does your tach refresh.

 

[Stump Shot]

I've gone too lean trying to do the Stihl saw tune before. You can check the color of your spark plug to verify. Should be a tannish brown in color if white, or light grey it's too lean.
If while cutting you can hear it four stroke after lifting out of the cut and disappear after going back into the cut, that's usually about right for your saw's maximum, take note with your tach then.

 

[JasonRKBA]

Not sure what four stroking means. It doesn't feel like it wants to die just kinda "wawawa".

 

[Clemsonfor]

You want to hear 4 stroking wide open not under a load. It will sound just like you describe and as soon as you put it into the cut should clean up and sound smooth like waaaaaaaa, and as soon as you lift up pressure should go back to 4 stroking like waaawawaawawa.

The less restrictive your mufflers are the easier this is to hear.

Limited coils can also screw you up, sound like 4 stroking bit it's the coil cutting out.

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[JasonRKBA]

Not sure about the refresh. Its the cheap kind you wrap the wire around the plug wire. On the 028 super I got it up to 12,600. The manual says 13k. I actually backed it off to just over 11k because I was a little concerned I may burn it up.

 

[JasonRKBA]

Cheap Chinese 290 coil I dropped in to eliminate the points. Gonna buy oem and see how it does. Great response. Thank you!

 

[Gary Courtney]

Cheap Chinese 290 coil I dropped in to eliminate the points. Gonna buy oem and see how it does. Great response. Thank you!

you running an older saw?

 

[JasonRKBA]

Yes sir.

 

[JasonRKBA]

Rebuilt two years ago. Seals, top end, fuel line, filter, carb rebuilt, impulse line, manifold.

 

[Simondo]

Question for the pros. I've always tuned by ear and my saws have ran well. I have placed a tach on a couple and see that they are running around 1500rpm less than the stihl manual suggests as max rpm not under load. While trying to increase the rpm using the tach it feels as I may be pushing a little to hard. And both that I've done this with sorta pulsed it the top end. Is this just par for the coarse? Or should I back them off as they where.

Thanks. Jason.

Jason.
A few things to take into account along with the quality of the Tac you use to take any readings (0.5 second re fresh rate is good).
Is the saw coil RPM limited ....
The heat of the saw when you make the adjustment...
The fuel to oil ratio that the saw will run on.. IF.. its different to the mix your using to tune the saw on...(this is important if your working on saws that are not yours)
Air filter state....
Is the saw in a good overall state and well maintained.....
Is the saw going to be used for milling....
I always ......Tune with the bar and chain on plus cut for a test, then check

These are some things to take on board and can help form the result in how close the saws RPM can/should be set to the makers guide.
Myself...I do use a Tac (PET 302) for the final tune ...even with a saw that is RPM limited as it can still be to lean or to rich.
On a customers stock saw I stay just under the makers MAX by 200-300 rpm to allow for a bit of latitude .
The... "free load RPM " with a well warmed up saw is the best way to get the right state of tune through the rev range as per the manufacturers specs.

 

[JasonRKBA]

Im running 45:1. I try to be conservative with the mix. No milling just using it for firewood and the occasional tree that falls. We have other saws on the farm we use for the heavy work, we call those the farm saws then there are my saws. Four houses on the farm all family. I definitely had the bar and chain on it but the tach is a cheap ebay special. The saw is in great shape. I always run it dry and hang it in the basement by a dehumidifier after blowing it clean.

I don't work the farm but a do most of the maintenance on the equipment.

 

[JasonRKBA]

Pictures help tell a story. I actually have a laser tach also but its a little more difficult to use.

 

[Clemsonfor]

45:1 is not too conservative. Many here myself included run 32:1

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[fearofpavement]

That saw never had points. I'm confused by that statement of "eliminating the points"

 

[JasonRKBA]

Ok. I have two the other is a WB. I may have changed it on the other one. I know for a fact one of them did.

 

[Wonkydonkey]

Umm interesting my you tube link, just seems to be a pic now ? And now it’s back, how strange

 

[Simondo]

Im running 45:1. I try to be conservative with the mix. No milling just using it for firewood and the occasional tree that falls. We have other saws on the farm we use for the heavy work, we call those the farm saws then there are my saws. Four houses on the farm all family. I definitely had the bar and chain on it but the tach is a cheap ebay special. The saw is in great shape. I always run it dry and hang it in the basement by a dehumidifier after blowing it clean.

I don't work the farm but a do most of the maintenance on the equipment.

I see no reason not to set the free RPM to 12500-12800 with your Stihl 028.