Rate Stihl's Advice on Chain Tension

[Paul Bunions]

I think I may be tightening my chains too much.

A lady mechanic with a Youtube channel says to tighten your chain until you can only pull three links away from the bar. The big problem here is that a long chain has to be a lot tighter than a short chain to get to that point. On a 24" bar, I have to crank it pretty good.

A Stihl video says to tighten until the chain snaps back against the bottom of the bar when you pull it away. Sound right? I guess they ought to know.

 

[ZeroJunk]

Back in the day when about all were hard nose bars you ran them as loose as they would stay on because they made more power that way.

FWIW

 

[huskihl]

No idea why anyone would give instruction like the first video. I’d have to believe that a12 year old girl doesn’t pull up on the chain quite as hard as a ham fisted 300 pound guy like myself. I bet if she can get 3 drive links out of the rail I can grab it and get 8 to show with the same tension. Just seems stupid.

Adjust the slack out of the chain until it comes up and hits the bar on the bottom. Tighten the nuts up, start it, run it around a few times to get some oil on it, and then recheck. If needed tighten it up again if it’s not touching the bottom rail

 

[drumbum]

I like to tighten until the chain comes up to the bottom of the bar,...and then just a touch more.
I don't like bar wear at the tip.

 

[Old2stroke]

Remember to adjust the chain with the bar tip held up, this is the loosest chain position for the bar and it is the position where it will end up when you apply a lot of pressure on the bar to make a dull chain cut. Spool the chain around until you find the place where it is the loosest (if there is one), then adjust tension until the chain just touches the bottom of the bar (no gap or sag off the bar), tighten the nuts and spool the chain around the bar manually, it should travel smoothly and easily. Too tight is NOT good.
Checking tension by seeing how hard it is to pull the chain off the bar is the least accurate method and should only be used on electric saws where you can't manually pull the chain around the bar.

 

[pdqdl]

Back in the day when about all were hard nose bars you ran them as loose as they would stay on because they made more power that way.

FWIW

And a whole lot less heat and worn out chains. As far as that goes, that is still true today, even with roller noses.

I had a training session with the owners of a cemetery where I do tree work. They wanted me to evaluate why one of their saws wouldn't cut, despite having a freshly sharpened chain. Along the way, we discussed how to tension a chain, how much to tension, and why you might like it looser or tighter. They were appalled to learn how loose I leave my chains, but I advised them for their little 16" & 18" bars, they should tighten them up about the same as your posted video.

Nobody ever seems to mention temperature when discussing how tight the chain should be. If it's smoking hot, don't tighten it that much!

 

[pdqdl]

No idea why anyone would give instruction like the first video. I’d have to believe that a12 year old girl doesn’t pull up on the chain quite as hard as a ham fisted 300 pound guy like myself. I bet if she can get 3 drive links out of the rail I can grab it and get 8 to show with the same tension. Just seems stupid.

Adjust the slack out of the chain until it comes up and hits the bar on the bottom. Tighten the nuts up, start it, run it around a few times to get some oil on it, and then recheck. If needed tighten it up again if it’s not touching the bottom rail

I don't run my chains quite that tight. They last longer and run cooler when loose.

I let my chains get very loose, so loose that newbies would have trouble throwing chains when they are handling the saw.

 

[MacAttack]

I think getting the chain tension just right is more of an art than a science, from years of running saws and working on them. Loose enough to spin free without drag, and without letting em hang off the bar. I see no benefit to running a chain real loose, that just ends up with that funky wear on the top sprocket end of the bar where the loose chain is slapping against the bar.

 

[pdqdl]

I've seen that too, but never figured out why it happens. It is much worse on longer bars, too.

 

[PJwoodcutter]

Not to mention too tight of a chain is hard on bearings, seals and rim sprockets.

 

[lone wolf]

Not to mention too tight of a chain is hard on bearings, seals and rim sprockets.

And can break cranks.

 

[MacAttack]

Indeed....running a chain too tight is much worse. It will wipe out your clutch side crank bearing.

 

[stihltech]

If it is on the internet it must be true.
They should just discontinue operator manuals.

 

[lone wolf]

If it is on the internet it must be true.
They should just discontinue operator manuals.

Wait, let me check YouTube and what ever it says is what I will do

 

[Paul Bunions]

Guess I'll go with Stihl. Thanks for the help.

Before I saw her video, I was just adjusting the saws so the chain ran freely without falling off. I guess I was doing it right.

 

[Marley5]

I'm constantly looking at my chains, want them right.

 

[PV Hiker]

Agree that do it enough you get a feel for it. My 20 in bar has a different feel and tension than my 36 inch bar.