Stihl Saws/Chain Compatibility

oldballs · Nov 21, 2021

Here is my question:

I have a 11 YO MS 290 "Farm Boss" and a brand new MS 261. Can I interchange the chains between the two saws? The MS 290 has 8 teeth in the drive sprocket; whereas the MS 261 has a smaller sprocket with 7 teeth. I use 16" and 20" bars. Both "bars" have 11 spikes on the nose of the bars. The Farm Boss chains are low kickback 26 RMC 3 chains. And the MS 261 chains are 26RS "Supercut".

Thanks,
Mike

RandyT · Nov 21, 2021

At long as the drive link count is the same it should be fine.

dodge man · Nov 21, 2021

I’m going to say no but I’m not sure.

hslogger · Nov 21, 2021

The bars should have gauge engraved on them. as in o63 or 058, etc. That determines the garoove and accompanying drive sprocket. They need to be the same. If the saws have different gauge requirements, the chains shouldn't be switched out to one another.

RandyT · Nov 21, 2021

hslogger said:
The bars should have gauge engraved on them. as in o63 or 058, etc. That determines the garoove and accompanying drive sprocket. They need to be the same. If the saws have different gauge requirements, the chains shouldn't be switched out to one another.

The 26 described in the OP is .063 gauge .325 pitch. Both saws use the same bar mount so the bar and chains will interchange between the saws. Actually even if the gauge didn't match, as long as the bar and chain was switched as an unit they would still interchange.

hosspuller · Nov 21, 2021

Saw chain is grouped by Gauge of the chain and pitch. The bar should match the chain gauge. The pitch has to match the drive sprocket and the bar nose sprocket if so equiped. Any chain that the matches the gauge and pitch can be used. The number of drive links determines the bar length...
The number of teeth of the drive sprocket is like the axle ratio of a vehicle. The lower the number the less torque the saw engine has to have to pull the chain... Conversely, the larger the sprocket, the faster the chain will be pulled at the same engine RPM

For the OP question... check the gauge and pitch of each chain. You can check for pitch by comparing a length of chain side by side. If the links match, the pitch is the same. If the chain guide thickness is the same, then the gauge is the same. Obviously, the chain length has to match the bar length. 16" bar to 16 loop / 20" bar to 20 inch loop

s219 · Nov 21, 2021

Depends. Normally the 290 runs 3/8"-0.050" chain and the 261 runs 0.325"-0.063" chain, but you can configure either saw to run either chain by changing the bar and drive sprocket. You would have to know what is on each saw to say for sure. They can be sold in either configuration depending on how the dealer wants to do it.

RandyT · Nov 21, 2021

s219 said:
Depends. Normally the 290 runs 3/8"-0.050" chain and the 261 runs 0.325"-0.063" chain, but you can configure either saw to run either chain by changing the bar and drive sprocket. You would have to know what is on each saw to say for sure. They can be sold in either configuration depending on how the dealer wants to do it.

In the original post the OP listed the 290 with 26rm chain and the 261 with 26rs chain. Both are .325 pitch .063 gauge chains. The 290 is semi-chisel and the 261 is full chisel