2000ssm6
Stihl User
im going to be running a 3/8 chain on my 026 as well with a 16 inch b&c
Go for it, that is what I run on mine, pulls great also.
im going to be running a 3/8 chain on my 026 as well with a 16 inch b&c
So then why do they put .325 chains and smaller sprockets on smaller displacement saws? I meant no offense to you or the types of wood out there. But I've ran several 029 supers with 18" bars and .325 chains. IMO, increasing the sprocket size and or widening the kerf would slow the saw too much.
Are those usually sold with 20" bars? The reason I ask is that I'm considering switching the drum & spur on my 290 to a 3/8" rim sprocket to simplify my bar and chain types among my saws. I like running a 20" bar (more reach. less bending over).
The 290 I ran had a 20 inch Farm Boss logo Stihl bar specifically made and marketed for the 290, in 3/8". Ran great. Also I could swap them out to and from my other larger saws. One reason I wanna flip to using a 260 from the 250... then I can have all the same type of B&Cs on all my saws, and have one file size for sharpening. Then I will also get a roll of 3/8 chain and be done with buying loops. I suppose I could get a rim drive for a 270 and do the same thing though? :monkey:
Thanks for the info! That's where I'm headed. I got the standard 290 for my area (spur sprocket, 20" FarmBoss logo bar in .325 .063). The problem is that the $$ I put into a 290 conversion to 3/8" could be put toward a 260. Darn CAD!
Oregon's website shows actual sizes of their rim sprockets and this would explain it better. When you see the pics, .325 x 7 looks a heckuva lot smaller than .325 x 8 and 3/8 x 7. Changing drive sprocket sizes makes a huge difference on smaller saws.That is a good question. I dunno why they only offer .325 on the 270, but they offer .325 or 3/8 on the 260 which has less power. The kerf issue is funny. Comparing .325 std. kerf to 3/8 std. kerf cuts, they are about the same width. If you cut the same width out of a log, it will require the same amount of power. So I do not see all the raving about .325. More drivers per inch would equate to more torque delivered to the cutters with the same size and pin count rim. But they have higher pin count rims with about the same size rim diameter so that the difference cancel out. Doing the math, here is the rough comparison:
Large format .325 vs 3/8 (.325) chains and rims:
Drive links per 100 feet of .325 = 1840
Drive links per 100 feet of .375 = 1640
Rim diameter of 8 tooth .325 sprocket = 1.45 inches
Rim diameter of 7 tooth .375 sprocket = 1.40 inches
Comparing the 8 tooth .325 sprocket to the 7 tooth .375 sprocket:
1840 - 1640 = 200 and 200 / 1640 = 12.2% more cutters per length for .325 chain
8 - 7 = 1 and 1 / 7 = 14.3% more spin delivered to the .325 chain per rev
Comparing these and the roughly 2% difference in radius in the rims, it seems like they pretty much all cancel out, and you have about the same torque and chain speed delivered to both types of chain. If the kerf is about the same, then I do not see the case for .325 being any better than 3/8 chain. Actually, with more cutters per inch, it seems like the .325 chains would be more prone to bog down than 3/8.
Now in the IPL for the 290, they list a 7 pin rim for the .325 size. So that may be the only real reason that I could see for using .325 chain on that saw or the 270; adding the option for more torque at the expense of chain speed.
the 026 i got is set up for 3/8 right now it has a sprocket sleeve? it has the original sprocket on it but it has a deal for a 3/8 chain over the sprocket, i know you guys are prolly gonna laugh at me for not knowing what it is but im not what you might call a whiz when it comes to saws. anyway just curious what its actually called and wondering if it would be better to just get a sprocket set up for 3/8. somone said it was about 100$?
Rim. Drive rim. The rims are usually around $5-10.00 each. Pull off the E-clip and washer and pull the old rim off and replace with a rim of the same pitch. If you change pitch it becomes more expensive.
yeah..i want to run 3/8 i just dont think its a good setup on it. and i guess anything thats 5-10 dollars to convert your saw to 3/8 prolly isnt the best bet. ill spend the extra money.
hm what would be the advantages to converting it to spur?