New MS 390

[boisblancboy]

Hey guys, im new to the board but not new to cutting wood.  I have been using my dads MS290 for a few years now to cut firewood and finally just got my own.  Because of my lack of research I bought a MS390 or I would have probably gotten a MS361.  Is there any aftermarket parts I install later down the road?  I have heard you can do something with the exhaust but havent found any info on it yet.

Though I am very happy with the price of my new 390 and considering I have used a 290 which is the same weight as the 390.

Anyway, I am just proud of my new purchase and happy with the price, but like I said would have probably went with the 361 if I knew better, just hope I dont regret it.

If anyone has any advice or reviews I would love to hear them.

[sawguy21]

Welcome aboard. You are right, the overwhelming favorite here is the MS361. However, your 390 is a good farm/ranch/weekend warrior saw although kinda heavy. Don't worry about hopping it up, as long as it is adjusted for best performance and the chain is sharp you will do just fine. If you really want speed, step up to the 361.

[boisblancboy]

I cut firewood for myself but on the side of my full time job, me and my buddy cut around 100 face cord a year to sell.

I know from personal experience that a well sharpened chain can really make your saw look like it is high preformance.

Just hope im not sorry down the road, although it is still quite an upgrade from running a 290 for years wouldnt you agree?

[Cut4fun]

Open the muffler from the factory 2 small slits and adjust carb for the flow and the 290 picks up at least 20% and last one I done picked up 23%. I would say the 390 could and  would see the same benefits. 20 mins time is all it takes if you know your way around the saw, if not and close by come over. It's worth it IMHO.

Where the 2 slits are I put another hole in the middle of them plus open the 2 slits up wider. Then I made 3 holes above top of cage and 2 bigger holes inside of cage. Really picked up the cut times 23%. Then if cutting clean wood, not dirt or sand impregnated wood. Take the green stihl RM chain off and get you some yellow stihl RSC and you gain another 50% quicker cut time from my experience. Equals cut faster get more done, quicker to the next step.

[ErikC]

 I bought a used 039 years ago for firewood, and still use it quite a bit. There's nothing wrong with your 390, it's going to serve you well if you take care of it. I have a 290 also, and you're right about it being a step up, but they all have their use if they run right and cut good.

[Ianab]

The 290-390 range of saws are designed for part time users, firewood cutters, farmers etc. People that need a decent reliable saw. The 390 should give you the same good service the 290 has, just cut a bit quicker.

Now if you are using a saw every day then the slightly lower weight, slightly more power and longer life of the 361 makes the extra cost worth it. Otherwise, you have the right saw for the job.

Yes you can modify the muffler. The muffler design is a trade-off between power, noise and clean burning of fuel. You cant have all three perfect. So if you open up the exhaust hole on the muffler you can get more power, but more noise and not quite as clean fuel burn. I would run it for a while like it is, just in case you need a warranty claim. If the saw dies the mods may be grounds to refuse a warranty, even if the mod didn't cause the problem.

Ian

[ErikC]

  I think modifying a 390 is kind of a waste of time. It will cut fine for what you want and need as it is. If you need a hot rod get a saw that's already at the top of power to weight, like the 460 or 660, and go from there. If you needed a more powerful saw than the 390, there's several off the shelf, and I'm sure you would have gotten one right?  JMO

By modify I mean more than just a basic performance tune-up like cut 4 fun or Ian is talking about.

[nmurph]

a simple muffler mod will add close to .75hp. why not have the most power to weight possible from a given saw?

[ErikC]

 Both posts I referred to mentioned a simple muffler mod. I was talking about replacement mufflers, and some of the other expensive aftermarket tricks guys will do. Just seems if your going to go to that trouble you should have something that's already at the top of the heap from the manufacturer. The 390 is a good saw but it's not the top of the heap. That's all.

[nmurph]

the OP mentioned AM parts to make the 390 run better. you can buy modded mufflers for this saw but it is a waste of money. a drill and a grinder and about 10 minutes of time will produce the same result.
as for the comment about MM saws wasting fuel, this would only be a result of an improperly tuned saw. all 2 strokes expell some amount of unburnt fuel. this is what gives you the 4-stroke that is necessary in proper tuning. a MM saw that is properly tuned will not expell any more unburnt fuel than a saw which has not had the muffler opened.

[ladylake]

Open the muffler from the factory 2 small slits and adjust carb for the flow and the 290 picks up at least 20% and last one I done picked up 23%. I would say the 390 could and  would see the same benefits. 20 mins time is all it takes if you know your way around the saw, if not and close by come over. It's worth it IMHO.

Where the 2 slits are I put another hole in the middle of them plus open the 2 slits up wider. Then I made 3 holes above top of cage and 2 bigger holes inside of cage. Really picked up the cut times 23%. Then if cutting clean wood, not dirt or sand impregnated wood. Take the green stihl RM chain off and get you some yellow stihl RSC and you gain another 50% quicker cut time from my experience. Equals cut faster get more done, quicker to the next step.

  Yes open the muffler, I think the homeowner and mid range saws come with a more clogged up muffler than the pro saws and gain quite a bit with a muffler mod.  Most likely the 290 and 390 use the same muffler, makes me think the 390 will gain even more than the 290.   Steve