Easy big gains for CS-590?

[Boatswain]

Hey all, I somewhat recently purchased a basically new CS-590 from a local pawn shop, (immaculate shape, guaranteed only used one time if at all, only payed 290$ for it.) And I'm trying to turn it into an east coast fallers type saw, I've got my dual spikes and full wrap aluminum handle with a 20" Tsumura solid core, but I want to go up to a 28" bar like the 620P, and I'd like to give my 590 a little more power to pull something like that, I'm not considering porting it at this time as I really don't want to ruin it because it runs great as is with a 20", I'm just wondering if a 620P Coil and carburetor really give it the gains it needs? I'm currently looking at popping the cylinder and swapping a Lil' red barn pop up 620P piston as I'm convinced that would give me that torque I need to run a bar like that comfortably.

Any input would be appreciated, Thanks.

(P.S. I did do a muffler mod, drilled a 3/8" hole to bypass the baffle and cut out some of the deflector shield.)

 

[Cynfawr]

Tinman on YouTube has a series of videos about modding this saw that you might find useful.

 

[Ronie]

I don't think you'll see any gains with the coil and carb change except it will be easyer to tune with the unlimited coil.

 

[K-techcowboy]

Hey all, I somewhat recently purchased a basically new CS-590 from a local pawn shop, (immaculate shape, guaranteed only used one time if at all, only payed 290$ for it.) And I'm trying to turn it into an east coast fallers type saw, I've got my dual spikes and full wrap aluminum handle with a 20" Tsumura solid core, but I want to go up to a 28" bar like the 620P, and I'd like to give my 590 a little more power to pull something like that, I'm not considering porting it at this time as I really don't want to ruin it because it runs great as is with a 20", I'm just wondering if a 620P Coil and carburetor really give it the gains it needs? I'm currently looking at popping the cylinder and swapping a Lil' red barn pop up 620P piston as I'm convinced that would give me that torque I need to run a bar like that comfortably.

Any input would be appreciated, Thanks.

(P.S. I did do a muffler mod, drilled a 3/8" hole to bypass the baffle and cut out some of the deflector shield.)View attachment 948534

I know just a coil and carb you gain very little to no noticeable power gains. Not sure with a pop-up but if you do that you might as well get a 620 jug to go with it as I've heard porting is different then the wolf. That would definitely get you there with those 4 things and a muffler mod. Oh and remove the black diffuser in air filter as you gain over 1cfm more air flow you'll just have to come up with a spacer to replace it so you can snug the filter down. I too just got a new timerwolf that had bein fired once but never bein in the wood and a sealed in the box cs3510 for 500. Both are amazing saws the 3510 is zippy and so light and in the wood I can't imagine a smoother ride then the 590. I want to do the same to my 590 cause it seems porting them just turns into a nightmare but I might do like a light woods port and polish with no change in timing idk for now I might delete the base gasket and run it for awhile before I start cutting up a $200 cylinder.

 

[K-techcowboy]

I don't think you'll see any gains with the coil and carb change except it will be easyer to tune with the unlimited coil.

Limited or not you have to tune in the wood so it doesn't matter besides you can't properly tune anything unless its under variable load situations hints why Inertia dynos were invented.

 

[K-techcowboy]

Tinman on YouTube has a series of videos about modding this saw that you might find useful.

Except after he ports it. Lol but yea I love that guys stuff he still hasn't finished that build though I wish he would.

 

[K-techcowboy]

Hey all, I somewhat recently purchased a basically new CS-590 from a local pawn shop, (immaculate shape, guaranteed only used one time if at all, only payed 290$ for it.) And I'm trying to turn it into an east coast fallers type saw, I've got my dual spikes and full wrap aluminum handle with a 20" Tsumura solid core, but I want to go up to a 28" bar like the 620P, and I'd like to give my 590 a little more power to pull something like that, I'm not considering porting it at this time as I really don't want to ruin it because it runs great as is with a 20", I'm just wondering if a 620P Coil and carburetor really give it the gains it needs? I'm currently looking at popping the cylinder and swapping a Lil' red barn pop up 620P piston as I'm convinced that would give me that torque I need to run a bar like that comfortably.

Any input would be appreciated, Thanks.

(P.S. I did do a muffler mod, drilled a 3/8" hole to bypass the baffle and cut out some of the deflector shield.)View attachment 948534

Haha I just put those same dogs on mine. They work decent but the powder coat is trash. Looks good bro.

 

[lostone]

I don't mean this to be negative but by the time you put the dogs, bar and full wrap (assuming you also bought all the parts to properly mount it to saw) on you could have bought a 620. I know I have gone the same route as you did and replaced the bar cover, dual dogs, rim/drum, carb bypass, front handle, Bar (Sugihara bar), muff moded, ported, and taken squish to .022. If I had it to do over again I would have bought the 620 and saved money LOL. I still believe a 28" bar on a 60cc saw is being overly optimistic, if you are needing a saw that will run a 28" regularly then you should check out the 7310.

 

[K-techcowboy]

I don't mean this to be negative but by the time you put the dogs, bar and full wrap (assuming you also bought all the parts to properly mount it to saw) on you could have bought a 620. I know I have gone the same route as you did and replaced the bar cover, dual dogs, rim/drum, carb bypass, front handle, Bar (Sugihara bar), muff moded, ported, and taken squish to .022. If I had it to do over again I would have bought the 620 and saved money LOL. I still believe a 28" bar on a 60cc saw is being overly optimistic, if you are needing a saw that will run a 28" regularly then you should check out the 7310.
View attachment 951424

This is true if I had paid retail for the saw but I only paid half for it brand new from the owner of a tree service so he didn't have a problem letting it go cheap. Also im one to look for deals and patent enough to get the best price I can. Plus I like building stuff like this to be better and more powerful then its pricier setup model. All said and done ill have alittle less then 500 in the saw and more power then a 620. Thats funny cause I was just looking at the 7310 today. Looks like a nice saw. Also looked at makitas 80cc beast. I kinda want to get it just to be different

 

[GoBigRed]

I don't mean this to be negative but by the time you put the dogs, bar and full wrap (assuming you also bought all the parts to properly mount it to saw) on you could have bought a 620. I know I have gone the same route as you did and replaced the bar cover, dual dogs, rim/drum, carb bypass, front handle, Bar (Sugihara bar), muff moded, ported, and taken squish to .022. If I had it to do over again I would have bought the 620 and saved money LOL. I still believe a 28" bar on a 60cc saw is being overly optimistic, if you are needing a saw that will run a 28" regularly then you should check out the 7310.
View attachment 951424

I agree also, but damn its fun to hotrod crap and make it your own. I know it’s work and time and effort, but modded saws are just cool AF.

 

[lostone]

This is true if I had paid retail for the saw but I only paid half for it brand new from the owner of a tree service so he didn't have a problem letting it go cheap. Also im one to look for deals and patent enough to get the best price I can. Plus I like building stuff like this to be better and more powerful then its pricier setup model. All said and done ill have alittle less then 500 in the saw and more power then a 620. Thats funny cause I was just looking at the 7310 today. Looks like a nice saw. Also looked at makitas 80cc beast. I kinda want to get it just to be different

LOL, well your definitely smarter than I am, I bought the one I have (well actually my sons now) from the big box store @ $400, the Sugi bar alone was over $125 plus shipping from over the pond then the front handle if I remember correctly set me back around $90 with all the extra plastic parts to do it properly. The Rim/Drum setup was around $60, and I cannot remember what the bar cover and spikes cost.
I did this one fairly early on so parts and prices where not in my favor. Port numbers on this one where pretty good from the factory and I only did light work on the upper transfers, I did remove the base gasket then had to turn off around .017 to end at .022 I believe it was and did the carb bypass and muffler mod.

 

[lostone]

One MAJOR thing Echo did to the 7310 that I wish the 590-620 had is the bar mount, They went to the large husky mount on the 7310 instead of the Mac mount the 590-620 have, this gives you a lot more options for bars.

 

[K-techcowboy]

I agree also, but damn its fun to hotrod crap and make it your own. I know it’s work and time and effort, but modded saws are just cool AF.

Yes they are especially cause you did the work and built it for you and your purpose. I love being able to budget build something that's equal or better to its over-priced predecessor. I built a nasty little 55cc chinese saw that easily out runs my 590 with a muffler mod and probably any thing else around the 60cc range. That saw has done nothing but impress me since day one and the engine components look better than anything I've seen sthil make so far. I almost think the piston was a forged piston by the machining marks and the work to the cylinder was beautiful. Everything was smooth, straight and open. I barley did any port work and its a straight screamer

 

[Bronco]

Hey K tech, could pls share name of the saw-(clone or chinese) make with the big gains? Thks man...

 

[GoBigRed]

Yes they are especially cause you did the work and built it for you and your purpose. I love being able to budget build something that's equal or better to its over-priced predecessor. I built a nasty little 55cc chinese saw that easily out runs my 590 with a muffler mod and probably any thing else around the 60cc range. That saw has done nothing but impress me since day one and the engine components look better than anything I've seen sthil make so far. I almost think the piston was a forged piston by the machining marks and the work to the cylinder was beautiful. Everything was smooth, straight and open. I barley did any port work and its a straight screamer

Amen brother. Same here. I’ve mentioned it before but my Mac 10-10 with her mods out cuts my buddies 361c. Yes, the Stihl is choked down with its sensitive ear muffler and fuel efficient timing and duration, but it’s still makes me laugh when that 54cc relic puts that high dollar 59cc saw to shame

the Mac cost me $40 but I will admit if I paid myself for the time I put in to it, then it might be be a little more. Good thing I’m cheap

 

[K-techcowboy]

Amen brother. Same here. I’ve mentioned it before but my Mac 10-10 with her mods out cuts my buddies 361c. Yes, the Stihl is choked down with its sensitive ear muffler and fuel efficient timing and duration, but it’s still makes me laugh when that 54cc relic puts that high dollar 59cc saw to shame

the Mac cost me $40 but I will admit if I paid myself for the time I put in to it, then it might be be a little more. Good thing I’m cheap

Oh me and you are on the same page then cause my second saw to buy was a 62cc(actual 54.6cc)chinese saw and I **** u not it cuts as fast if not fast then my cs590 and the build quality and machining in the engine is some of the best I've ever seen and as a motorcycle technician I've seen alot. The inside of my 028 wb looked like someone took a dump in it compared to that slightly moded $100 saw here's one pic. Keep in mind I cut firewood every day on my property and have bein beating this thing up for almost 3 months. Everything is straight flat and smooth all I did was widen everything. There piston material is the closest to being a billet one as I've yet to find in a saw. I'm a believer these cheap saws aren't cheap at all. Its a dereal pro 6220 btw

 

[K-techcowboy]

I have a question. How do we know the 620 coil isn't limited as well. Like has anyone ever had a 590 hit 18k rpm. I think there both limited just one gives you 1k or so more. I'm on the hunt for one I know doesn't have the microprocessor to limit rpm.

 

[K-techcowboy]

Hey K tech, could pls share name of the saw-(clone or chinese) make with the big gains? Thks man...

Mines a dereal pro 6220. I've done the basics to improve it and its pulling a 24in sthil chain on a echo bar. Through blackjack like a light saber.

 

[Red97]

I have a question. How do we know the 620 coil isn't limited as well. Like has anyone ever had a 590 hit 18k rpm. I think there both limited just one gives you 1k or so more. I'm on the hunt for one I know doesn't have the microprocessor to limit rpm.

I have had 15k+ out of the 620 coil bit no real power is made up that high.

 

[Brushwacker]

Yes they are especially cause you did the work and built it for you and your purpose. I love being able to budget build something that's equal or better to its over-priced predecessor. I built a nasty little 55cc chinese saw that easily out runs my 590 with a muffler mod and probably any thing else around the 60cc range. That saw has done nothing but impress me since day one and the engine components look better than anything I've seen sthil make so far. I almost think the piston was a forged piston by the machining marks and the work to the cylinder was beautiful. Everything was smooth, straight and open. I barley did any port work and its a straight screamer

What brand Chinese saw?
I have a Blue Max new in the box.