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MS 880 unlimited, clearly successful.

michpatriot

michpatriot

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Joined
Sep 18, 2020
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12
Location
mi
Well I've been tweak'n my 2018 MS880, after much murky fact finding online here's what I've ended up with..I fabbed up a second exhaust outlet using 1\2" stainless pipe. I set it over a 3\8" hole drilled in from the outside of the muffler into the exhaust passage behind the screen so as to retain the screen function. Next I pulled the carb limiters and installed a MS361 coil, and finished up with advancing the timing by filing .040 off the .080 thick crank key. So its a half a key advanced (super scientific). I tuned it in the cut with a 36" bar and .404 full chisel full skip. Absolute night and day between this setup and stock. Crisp throttle response and pulls a 8 pin sprocket pretty well in 30" dry ash with full skip. For those who follow this path I will caution that you need to run good 100% gasoline. No ethanol. I use 91 octane rec fuel from the pump and add octane booster to achieve around 95-96 octane. Setup like I have described you have the ability to tune in the cut and clearly hear 4 stroking. You also will have the ability to absolutely melt down your saw if you don't adjust correctly. I won't have my saws any other way. This saw is now running like one would expect a new saw to run..it will never be as crisp as a fully port adjusted, squish band worked saw done by any of the masters...but I like it now. I have the 7pin back on and full comp RS .404 back on the 36" bar and will probably save the 8 pin for GTG with a 25" bar but it did pull it surprisingly well. Later this week I have a tachometer coming and will get back with the rpm that its running now..it won't really chance my tune, I like it where its at, but it'll be neat to see the numbers..its a real work saw now.
Joel
 

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MFV

ArboristSite Operative
Joined
Oct 27, 2020
Messages
129
Location
Texas
Well I've been tweak'n my 2018 MS880, after much murky fact finding online here's what I've ended up with..I fabbed up a second exhaust outlet using 1\2" stainless pipe. I set it over a 3\8" hole drilled in from the outside of the muffler into the exhaust passage behind the screen so as to retain the screen function. Next I pulled the carb limiters and installed a MS361 coil, and finished up with advancing the timing by filing .040 off the .080 thick crank key. So its a half a key advanced (super scientific). I tuned it in the cut with a 36" bar and .404 full chisel full skip. Absolute night and day between this setup and stock. Crisp throttle response and pulls a 8 pin sprocket pretty well in 30" dry ash with full skip. For those who follow this path I will caution that you need to run good 100% gasoline. No ethanol. I use 91 octane rec fuel from the pump and add octane booster to achieve around 95-96 octane. Setup like I have described you have the ability to tune in the cut and clearly hear 4 stroking. You also will have the ability to absolutely melt down your saw if you don't adjust correctly. I won't have my saws any other way. This saw is now running like one would expect a new saw to run..it will never be as crisp as a fully port adjusted, squish band worked saw done by any of the masters...but I like it now. I have the 7pin back on and full comp RS .404 back on the 36" bar and will probably save the 8 pin for GTG with a 25" bar but it did pull it surprisingly well. Later this week I have a tachometer coming and will get back with the rpm that its running now..it won't really chance my tune, I like it where its at, but it'll be neat to see the numbers..its a real work saw now.
Joel
I am waiting on seals to fix up my older 880 I may try to pick your brain on some things later on this week
 
michpatriot

michpatriot

ArboristSite Lurker
Joined
Sep 18, 2020
Messages
12
Location
mi
I read about your woes with multiple meltdowns..some ideas come to mind, they may or may not be contributing factors. I would definitely be running a chain designed for ripping, and if you arnt handy with a file, buy a electric bench or wall mounted grinder. Keep the chain razor sharp. As for the saw problems, when the saw is back in shape I'd err on the rich side with the H screw, and make sure the main jet isn't partially plugged ..I like oil that really clings to the mixing cup and have been very happy with BelRay H1R mixed at 50:1 but I'm not milling the big stuff, bucking is what my saw is for mostly with a little bit of ripping here and there. I try to rip with less pressure on the bar and pull out of the cut partially with the bar keeping the bar oiled and cleaned out blipping the throttle. I don't run long rips without letting my saw breath, 30 sec max, then a little idling, then back at it. I think its probably a very tricky balance with a steep learning curve to rip big wood regularly and my guess is even a new saw won't take it for long if just one factor is off and gets critical. If you look to some of the foreigners videos ripping HUGE wood they are using just the tip of the bar and walking the top of the log..I think there is something to be said for not loading all the teeth in the cut, they have some very old stihl 090 cutting day in and day out, using just the bar nose dragging deep in the cut.
 
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MFV

ArboristSite Operative
Joined
Oct 27, 2020
Messages
129
Location
Texas
I read about your woes with multiple meltdowns..some ideas come to mind, they may or may not be contributing factors. I would definitely be running a chain designed for ripping, and if you arnt handy with a file, buy a electric bench or wall mounted grinder. Keep the chain razor sharp. As for the saw problems, when the saw is back in shape I'd err on the rich side with the H screw, and make sure the main jet isn't partially plugged ..I like oil that really clings to the mixing cup and have been very happy with BelRay H1R mixed at 50:1 but I'm not milling the big stuff, bucking is what my saw is for mostly with a little bit of ripping here and there. I try to rip with less pressure on the bar and pull out of the cut partially with the bar keeping the bar oiled and cleaned out blipping the throttle. I don't run long rips without letting my saw breath, 30 sec max, then a little idling, then back at it. I think its probably a very tricky balance with a steep learning curve to rip big wood regularly and my guess is even a new saw won't take it for long if just one factor is off and gets critical. If you look to some of the foreigners videos ripping HUGE wood they are using just the tip of the bar and walking the top of the log..I think there is something to be said for not loading all the teeth in the cut, they have some very old stihl 090 cutting day in and day out, using just the bar nose dragging deep in the cut.
Yes I think I have done a number of things wrong when I get this put back together I will start testing myself on what I am doing
 
michpatriot

michpatriot

ArboristSite Lurker
Joined
Sep 18, 2020
Messages
12
Location
mi
Well today my Still tachometer came in today so I fired up the 880. It runs crisp set to 12,400rpm, so ill run it a bit on the next job set there and see what the plug looks like after a few big logs.
 
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