I have a saw with an 18 inch bar taking chain .063 / .325 and 74 drive links. I am looking at buying a 100 ft roll of Oregon chain, but would like some help to ensure I buy the right chain. When looking up chains for 18 inch bars -063 .325 , there are some being advertised as 74 dl , 68 dl and others . How can an 18 inch bar with the same specifications of .063 and .325 take varying numbers of drive links and how do I tell if the 100 ft roll will deliver 74 drive links for my saw ? Any assistance would be greatly appreciated. Thanking you in anticipation and many thanks to those who have helped with my previous questions.
Help needed to understand chains
- Thread starter StihlSaw
- Start date
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18" is a nominal measurement from the saw body to the bar tip, this will be slightly different for different saws & also the bar itself could be 17.5" - 18.5". A wider bar or lager nose sprocket will also make a difference.
A 100' roll of .325" will give you almost 1850 drive links... that's enough to make about 25 chains.
Do you have the ability to break & join the chain? I would have thought if you were in a position to be using that much chain you wouldn't need to be asking the above questions
A 100' roll of .325" will give you almost 1850 drive links... that's enough to make about 25 chains.
Do you have the ability to break & join the chain? I would have thought if you were in a position to be using that much chain you wouldn't need to be asking the above questions
Bars/saws with different type mounts will vary in the distance to the drive sprocket, hence 68 vs 74 drivers.
Do you really need 100' of chain?
Do you really need 100' of chain?
Hundred Acre Wood
Full-time Slacker
The bar dictates the number of drive links (DL) it needs. Period.
edit: Here's an example of the markings on a Stihl bar (not my photo) that shows 74 DL for this particular 18" bar.
Look at the bar, or if the markings aren't there look up the spec for it. Or take the working chain off and count the DL. Different manufacturers (unfortunately) use different DL count for similar length bars, caused largely by differences in bar shape.
As an alternate solution, if you really going through a 100' of chain and you're running .325 on a Stihl, I'd recommend moving to a narrow kerf bar (Light 04 guide bar) and some Stihl 3690 chain (23RS Pro .325/.050"). It's full chisel narrow kerf and will cut faster and put less stress on your powerhead because it's cutting less wood.
edit: Here's an example of the markings on a Stihl bar (not my photo) that shows 74 DL for this particular 18" bar.
Look at the bar, or if the markings aren't there look up the spec for it. Or take the working chain off and count the DL. Different manufacturers (unfortunately) use different DL count for similar length bars, caused largely by differences in bar shape.
As an alternate solution, if you really going through a 100' of chain and you're running .325 on a Stihl, I'd recommend moving to a narrow kerf bar (Light 04 guide bar) and some Stihl 3690 chain (23RS Pro .325/.050"). It's full chisel narrow kerf and will cut faster and put less stress on your powerhead because it's cutting less wood.
M
Many thanks for your time and assistance.The bar dictates the number of drive links (DL) it needs. Period.
edit: Here's an example of the markings on a Stihl bar (not my photo) that shows 74 DL for this particular 18" bar.
Look at the bar, or if the markings aren't there look up the spec for it. Or take the working chain off and count the DL. Different manufacturers (unfortunately) use different DL count for similar length bars, caused largely by differences in bar shape.
As an alternate solution, if you really going through a 100' of chain and you're running .325 on a Stihl, I'd recommend moving to a narrow kerf bar (Light 04 guide bar) and some Stihl 3690 chain (23RS Pro .325/.050"). It's full chisel narrow kerf and will cut faster and put less stress on your powerhead because it's cutting less wood.
Many thanks for your time and assistance.
I agree with the above response. Having said that, the reason there are 18" 0.325 chains in both 74DL and 68DL has to do with the bar mount configuration. Stihl Pro saws (024, 026, MS260, , MS261, 034, 036, MS360, MS361, MS362 ect) run a DO25 mount and they take a 74DL chain. The homeowner grade 025/MS250 has a bar that's not as tall, and I think they normally run a 7 pin rim on the sprocket which is smaller diameter than an 8 pin or 9 pin that runs on the bigger saws. Therefore, the 025/MS250 only requires 68DL for the a 18" bar, where as the bigger saws require a 74DL chain. You might be able to fit a 68 DL on a saw running a D025 mount if you're running a 7 pin rim on the sprocket but it may still be too tight. I run an 18" bar on all of my saws that are 40cc to 70cc (Depending on the saw, I'm running 7 pin, 8 pin, and 9 pin rims), and I use 74DL chains on all of them. I do not own any homeowner saws (no offence intended or implied).
Many thanks. Didn't know you could have different pin counts. You learn something new every day . Thank you once again.
That’s a lot of chain for 1 saw. A roll will cost you $400+. And you need the tools to make loops…another $100.
It lets you tweak where you're at on chain speed vs torque. For example, since I only run an 18" bar with 0.325 chain on my 036 saws, they basically have more torque than really needed. I set them up to run 9 pin rims which increases my chain speed by over 10%. This lets me make better use of the torque that's available on these saws.
Hundred Acre Wood
Full-time Slacker
Now switch to .325 .050 NK (Stihl 3690 23RS Pro) and you'll really rip.
Howard Justice
ArboristSite Operative
100acrewood, is this Stihl chain available in loops? I presume it is a “yellow” chain. Thank you.The bar dictates the number of drive links (DL) it needs. Period.
edit: Here's an example of the markings on a Stihl bar (not my photo) that shows 74 DL for this particular 18" bar.
Look at the bar, or if the markings aren't there look up the spec for it. Or take the working chain off and count the DL. Different manufacturers (unfortunately) use different DL count for similar length bars, caused largely by differences in bar shape.
As an alternate solution, if you really going through a 100' of chain and you're running .325 on a Stihl, I'd recommend moving to a narrow kerf bar (Light 04 guide bar) and some Stihl 3690 chain (23RS Pro .325/.050"). It's full chisel narrow kerf and will cut faster and put less stress on your powerhead because it's cutting less wood.
Howard Justice
ArboristSite Operative
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Hundred Acre Wood
Full-time Slacker
Just to make sure you're aware, that's narrow kerf chain. You need a narrow kerf bar to run it.
Stihl says the B&C combo increases cutting performance up to 20%, and my experience believes it.
