MS251 Wood Boss bar/chain query?

[Keith N]

Hi all from sunny Brisbane Australia.

I have a Stihl MS250 Wood Boss that I've had for a few years and I'm puzzled about the bar/chain combinations recommended for this saw by any provider I have checked with on line. It has a 16" bar on it and a .325" pitch Stihl chain with 68 links and .063" gauge but wherever I go to look at bar and chain listings it tells me it should be 62 links and that the 68 is for the 18" bar ... I've measured the bar from the chainsaw body to the tip and it's definitely 16". Stihl's own official PDF data page says this as well so what gives ... I'm mystified?

 

[StarTech]

Ahhh, You found what I found last year about Stihl bars.and other bars. What they claim them to measure and what they do is two different things. They say you measure from the body to tip for bar length but they actually meas measure the tip to the tail of the bar. On the saw I was replacing the bar the co-called 18" bar was under 17". Don't remember which Stilh it was or the actual new length, just remember it to be way shorter what it claimed to be if measure from the body to the tip.

To me it is a con job done on the owner of the saw. Now some this may be the height of the bar being a lot more but I didn't have the time to research it or had an Oregon bar to compare to.

IF you have a .325 bar with 68 DL chain then it is classed as a 18" even if it measures less. Not a problem until you go to cut a 36" log where you actually need the full bar length. What you go by is the info printed on the bar itself and the actual DL count of the chain on the saw.

 

[ILENGINE]

Bar length are like lawnmower engine horsepower. What they claim is bar length and useable bar length are two different things. Some measure from the front of the saw to the end of the bar with the chain on the bar because you need to the chain to get the correct width, but then they throw a set of 1 inch log spikes out there which reduces your cutting length in some cases over an inch. What I have found is when they call for a 16 inch bar in reality it is a 15. the same with the 18-17 and 20-19 reference. Then there a few rare cases where they will actually call it a 15 17, 19, 21 but will have the link count of their longer even count brother.

 

[StarTech]

Bar length are like lawnmower engine horsepower. What they claim is bar length and useable bar length are two different things. Some measure from the front of the saw to the end of the bar with the chain on the bar because you need to the chain to get the correct width, but then they throw a set of 1 inch log spikes out there which reduces your cutting length in some cases over an inch. What I have found is when they call for a 16 inch bar in reality it is a 15. the same with the 18-17 and 20-19 reference. Then there a few rare cases where they will actually call it a 15 17, 19, 21 but will have the link count of their longer even count brother.

I would have thought it was the spikes too but that was not the case here on the bar I had to replace last year. Even the Stihl service showed how to measure the bar which I used and the figures just didn't match up.

I just wish that when they say you got a cutting length that they actually have that length.

 

[Fish]

Aftermarket suppliers some times get the drive link count different, I assume from different dimensions of their bar.

 

[StarTech]

Aftermarket suppliers some times get the drive link count different, I assume from different dimensions of their bar.

Yes they do as I got one customer that has an Oregon bar on Craftsman (MTD saw) that is one DL shorter but it is clearly label on the bar to this DL count. Customer just coming getting chains shorten for it until finally brought the saw in and I showed him that was simply buying the wrong chains. He griped a lot for me charging him the break, shorten, and mend his chains. Now he is happy just to buy the correct chains.

Now I did tell that when he wear the current bar out I be glad to put the correct bar to match his saw specs so it will not a be fight everytime he goes somewhere else for chains. 71 DL chains are not as common as the 72 DL chain his saw calls for.

 

[ILENGINE]

Aftermarket suppliers some times get the drive link count different, I assume from different dimensions of their bar.

I have a saw that the manufacturer calls for 106 links but the bar calls for 104. 104 or 106 both work but the 106 doesn't leave as much room for adjustment as the 104. Sold a saw a few years ago that originally had 78 links but sometime along the way they found a batch of older bars and started shipping them with the new saws. They were 79 links. So I sold the same model of saw with two different bar link counts. Try to keep that straight when the customer calls and says I need a new chain for the saw you sold me 3 years ago.

 

[Hammermechanicman]

Aftermarket suppliers some times get the drive link count different, I assume from different dimensions of their bar.

Correct. Nice thing about Stihl bars is they all have the pitch, guage and drive link numbers on the side of the bar so you can get an OEM or AM chain that fits. If i am looking at other brands you usually need to look at specs on a catalog page or count drive links and measure pitch and guage to get a replacement chain. And yes, i also hate the inch game with chainsaws. I bought a 36" bar for my MS660 clone. Found out real quick i ain't man enough to run it. Weighs a freakin ton! When you see guys on TV with big saws with 36" bars those guys are real men. Not a sissy like me.

 

[Fish]

Here is the 18" 68 drive link, in case folks want to see firsthand.

 

[ILENGINE]

Correct. Nice thing about Stihl bars is they all have the pitch, guage and drive link numbers on the side of the bar so you can get an OEM or AM chain that fits. If i am looking at other brands you usually need to look at specs on a catalog page or count drive links and measure pitch and guage to get a replacement chain. And yes, i also hate the inch game with chainsaws. I bought a 36" bar for my MS660 clone. Found out real quick i ain't man enough to run it. Weighs a freakin ton! When you see guys on TV with big saws with 36" bars those guys are real men. Not a sissy like me.

36" bars are fun. First rule is don't try to use it to cut stuff that is way smaller than the bar. You need the big wood to prevent having to hold the weight of the saw. 9-10 cuts per tank is about the average when cutting 36" and larger wood. Wait until you get into the even larger bars, like a stihl 59" that has enough bar flex when the saw is turned on its side to do a felling cut that it will throw the chain off of the bar if the end of the bar isn't supported when starting the cut.