MS290 Questions about Sprocket, Bar & Chain Set Ups

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

JP56

ArboristSite Operative
Joined
Nov 14, 2018
Messages
139
Reaction score
84
Location
CT
My MS290 (Series 1127) as purchased, is set up with a 7T Spur Sprocket running 18" & 20" bars with the .325 chain. My 18" & 20" bars are currently "Green" dot OEM bars marked Farm Boss, & I still have a 2md 18" bar that marked as "STIHL Rolomatic", which I noticed is a slightly different shape that the dealer sold me when I purchased everything. As for the chains they have been selling me, some have the "Green" & some have the "Yellow" Designation, & some are "26 RM3 Rapid Micro" & some are "26 RS Rapid Super".

I have several saws, & most of them are set up for 3/8 x .50. Only this one uses the .325 & I have 1 or 2 others that use the 3/8 x .43 & .63.

I would like to set them all up to use the 3/8 x .50 chain If Possible, so all I would have to do is order the different lengths or buy bulk & make my own as needed, especially with all this covid crap & supply "shortages" being driven by it.

My Questions:

1) What EXACTLY is the difference between using the Green Dot & Yellow Dot, and is using the one color chain on the other color bar ok?

2) What Exactly is the difference between Rapid "Super & Micro", is there an advantage of one over the other ?

2) Can I change my 290 Sprocket to a 7T Rim Sprocket & 18" & 20" bars that will run 3/8 chain?
 
I put rim sprocket setups on my 290's, makes switching from .325 to 3/8 chain as simple as a sprocket swap if you wanted to do so. If you put 3/8 chain on a 290 expect to run a 16" bar in order to pull and oil it decently. Using 20" .325 on a 290 it can barely oil it enough and chain speed is pretty slow in a big cut, keep your chain razer sharp and it does well enough, I would be afraid of ruining a 20" 3/8 setup from lack of oil and it would bog and cut too slow. I did turn a 290 into a pretty sweet modified 390 that would easily pull a 20" 3/8 but it cuts really great running the .325 20".
 
My MS290 (Series 1127) as purchased, is set up with a 7T Spur Sprocket running 18" & 20" bars with the .325 chain. My 18" & 20" bars are currently "Green" dot OEM bars marked Farm Boss, & I still have a 2md 18" bar that marked as "STIHL Rolomatic", which I noticed is a slightly different shape that the dealer sold me when I purchased everything. As for the chains they have been selling me, some have the "Green" & some have the "Yellow" Designation, & some are "26 RM3 Rapid Micro" & some are "26 RS Rapid Super".

I have several saws, & most of them are set up for 3/8 x .50. Only this one uses the .325 & I have 1 or 2 others that use the 3/8 x .43 & .63.

I would like to set them all up to use the 3/8 x .50 chain If Possible, so all I would have to do is order the different lengths or buy bulk & make my own as needed, especially with all this covid crap & supply "shortages" being driven by it.

My Questions:

1) What EXACTLY is the difference between using the Green Dot & Yellow Dot, and is using the one color chain on the other color bar ok?

2) What Exactly is the difference between Rapid "Super & Micro", is there an advantage of one over the other ?

2) Can I change my 290 Sprocket to a 7T Rim Sprocket & 18" & 20" bars that will run 3/8 chain?
I'm running a rim sprocket 20" yellow chain on my ms290 with know problems.
 
I put rim sprocket setups on my 290's, makes switching from .325 to 3/8 chain as simple as a sprocket swap if you wanted to do so. If you put 3/8 chain on a 290 expect to run a 16" bar in order to pull and oil it decently. Using 20" .325 on a 290 it can barely oil it enough and chain speed is pretty slow in a big cut, keep your chain razer sharp and it does well enough, I would be afraid of ruining a 20" 3/8 setup from lack of oil and it would bog and cut too slow. I did turn a 290 into a pretty sweet modified 390 that would easily pull a 20" 3/8 but it cuts really great running the .325 20".
to increase oil flow. I ENLARGE the bar oil holes on all of my saws. THEN use the screw to adjust flow.. In fact I'm running a 28 inch 3/8 Oregon bar with a Semi-chisel on my Echo cs 590..I used a dremel tool and small pointed grinding cone to open the oil hole.. It's an animal..IMG_20181223_194214_009.jpg
 
to increase oil flow. I ENLARGE the bar oil holes on all of my saws. THEN use the screw to adjust flow.. In fact I'm running a 28 inch 3/8 Oregon bar with a Semi-chisel on my Echo cs 590..I used a dremel tool and small pointed grinding cone to open the oil hole.. It's an animal..View attachment 969811
The CS-590 must have a real oil pump
The stock one used on ms290, 311 and 390 are adjustable but really really stingy. At the max setting it BARELY pumps enough to mist a sheet of paper off the tip with the saw screaming at max rpm for 4-5 seconds. I imagine with a aftermarket cylinder that turns lower max rpms it will suffer from even less oil delivery. I ended up modifying the oil pump twice to get what I would consider adequate output. Before It would use 1/3-1/4 of the bar oil per tank of gas and the thing would run almost a hour per tank, now it uses about half a tank and I think I can turn it up even more!
 
The CS-590 must have a real oil pump
The stock one used on ms290, 311 and 390 are adjustable but really really stingy. At the max setting it BARELY pumps enough to mist a sheet of paper off the tip with the saw screaming at max rpm for 4-5 seconds. I imagine with a aftermarket cylinder that turns lower max rpms it will suffer from even less oil delivery. I ended up modifying the oil pump twice to get what I would consider adequate output. Before It would use 1/3-1/4 of the bar oil per tank of gas and the thing would run almost a hour per tank, now it uses about half a tank and I think I can turn it up even more!
Bigger bar holes and angled too. Even the oil holes at the tension oil systems get it on my bars.IMG_20181204_204716_056.jpg
 
I have known several 029 and ms290,s to use the 20in 3/8 set up without oiling issues. If it currently is using over 75% of the oil in the oil tank to a tank of fuel , likely i think it will be enough with good oil. Difference in .325 is you will have more power in the cut primarily because. 325 rims are smaller then 3/8 gearing it for slower speed but more power and fuel consumption is usually more with the smaller sprocket . The .325 s advantage is in big cuts of wood. If you are cutting less then 15ish inch wood you should have decent power with the 3/8, doing a lot of bigger the benifit of .325 will be significant help for the saw and operater.
RM chain is better for average use and conditions. If you are good at sharpening and keeping it near 100% sharp RS is faster cutting.
No problem mixing yellow and green lable bars and chain. Read up on kickback and understand what you are dealing with and then decide what chain works best for you. I cut 40+ years, some professionally and use both. The newer green lable chain works very well in comparison to original versions.
 

Latest posts

Back
Top