MS251 Wood Boss bar/chain query?

[bertsmobile1]

Funny.
My suppliers measure the bar as the length from the tip of the bar to the front edge of the mounting slot.
This of course will always be 1" to 2" longer than the actual cutting length but the again computers & TV's measure the screen size as the diagonal distance.
The killer for me is the height of the bar as I get so many bars in with nothing left on them to identify which particular bar profile it is.
And when they do most of them are not listed as they are old bars of a discontinued profile.
I don't keep loops so it is not a problem for me
They either bring me the entire saw or go buy a loop from some one else.
What I do find regularly which is a right royal PIA is a different tooth count on the sprockets so again I have to get the saw in before I can order the sprockets.
Now I have always put this down to USA nanny state regulations as most US saws I fix have a higher tooth could so thus run the chain faster just like a lot of the decks I see have smaller pulleys than the US parts book specify

 

[Fish]

On the longer bigger bars, the drive link count can also be affected by the use of a 6 or 7 or 8 tooth sprocket.

 

[Keith N]

Ahh ... thanks for the replies and this all makes more sense now. I think I may have replaced the bar because there is nothing on it that says Stihl anywhere that I can see ... it must be a generic of some type and I possibly got a couple of Stihl chains as well at the time ... who knows, I loose track of these things these days! lol I'll need a new chain fairly soon and may replace the bar as well and at least thanks to the info received here I know that what I order will work if I order a correct bar and chain set. Interestingly the plastic bar cover that came with the saw says 45cm/18" so that must be what it came with when I bought it ... that MS251 came with either bar apparently, 16" or 18"

I love Stihl gear ... I have an FS250R Brushcutter that is by far the best brush cutter I have ever owned and is my third Stihl ... I wore two others out so you can imagine how much work the poor things do. The shortest lived of them was a four stroke FS130R which was great to use but seemed to have a shorter life than the two stroke that preceded it ... an FS120.

 

[Hammermechanicman]

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.

I normally have a 25" bar on it i use for most large felling and bucking. Only time the 36" goes on is to buck some big stuff. Oiler won't keep up with the 36 so i have to and pour oil on the bar about every minute or so. For most stuff i have a 361 clone with a 25" bar that fells and bucks most stuff and i have a 251 and 170 for light work and limbing. If something needs a bar bigger than 36" i am not man enough for the job.