browsing eBay I spotted the dirt cheap chainsaws. $118 for a black and yellow 52cc with 18" bar, shipped from NJ. Figured they couldn't be any good but had to see one for $100 and figured if it didn't cut, it wasn't a big deal.. I have used real saws but never owned anything except a poulan predator... Anyway it actually runs ok, looks ok and is built ok. Worth what I paid. 3 tanks of fuel so far and i put Oregon 34LG chain on it. Thinking it has to be slagged up inside since I have experience with the 66cc china bike engines ( nothing comparable US made ) and they need porting to get any HP, but they are very different than a chainsaw engine.... Anyone know what I should do for it? It runs along side an MS291 that is stock but can tell its not the high dollar saw. I bought it as a 52cc but it has 5900 labels so it might really be 59cc
port a china saw?
- Thread starter matt167
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DO the standard things... check the squish, see if you can remove a base gasket or trim the lower cylinder to get to .020 or there abouts. Do a muffler mod and see what you have. Find the port timing with a degree wheel and then post those numbers... might have ground to till just working the intake along with the compression increases.
at what point does the compression start to hurt a saw? I mean for reliability. I kno a 2 stroke gets great gains from compression increase. But that's increased stress on the crank and starting mechanisms, so where's the happy medium? Currently the saw is a 2 pull starter. The throttle lock does not need to be used. It's just dead reliable. I don't want to make a 10 second cutter that lasts 10 cuts.. My experience with 2 stroke porting goes as far as those 66cc china bike engines. They took a slant head to bump the comp just a little, and smooth casting slag on the exhaust and intake ports.. Just smooth made a huge difference in the way they ran... The china saw 4 strokes a little when cutting vertical, bar in the air but otherwise, it runs good
For my saws, I try to keep the compression in the 180-185 psi range. They run crisp and I haven't seen any bottom end issues. Some of the "cookie cutter" saws push 200lbs and beyond which in my mind seems a bit much even though I don't have data to support that with my own saws.....as I get what I'm looking for with the numbers I use. Also I'm not a fan of pushing RPM limits for power for my work saws. Typically I try to get more torque out of them vs. more RPM.s hence the focus on modest compression gains. Same with muffler mods, modest changes there combined with reasonable compression goals can make tangible gains and I haven't seen any change in reliability over the life of the saws I've experienced. Having said that.... its possible your saw already is at those levels stock..... not likely but possible. AND before doing any type of mods, measure things. Have to check squish before doing anything that might effect deck heights. Its worth checking port timing as well before randomly changing things. If you are going to spend the time tearing into the saw to smooth rough casting in the ports, take the extra step. You might find its great where it is. There is a lot of numbers out there relative to 55-60cc saws so it shouldn't be hard to find good starting numbers. Also with some of the saws I've dealt with, the restrictions are things like manifold and carb size. All of the grinding in the world to make the intake and things down stream smoother doesn't deal with the core issue of restrictions upstream. Only port timing does, or going to larger components. Things like advancing the intake timing can help a tiny intake manifold/carb setup more than "polishing" that port. Just stuff to consider...
Also....if your happy with the saw, leave it alone! Sometimes taking a saw apart can actually allow you to identify and solve developing issues... and sometimes you add variables that can reduce its reliability. Every time you tear it down there is that blend of risk and opportunity. If someone is of the mind set its some ones else's issue because you took general suggestions of places to look literally with out the skill to quantify and evaluate when you get in there and create problems... leave it alone as well. Every one will be happier. WHICH is why for the far majority of people, the best place to keep a saw is.....stock, and within the boundaries of a warrantee program as defined by the manufacturer and supported by a good dealer.
Also....if your happy with the saw, leave it alone! Sometimes taking a saw apart can actually allow you to identify and solve developing issues... and sometimes you add variables that can reduce its reliability. Every time you tear it down there is that blend of risk and opportunity. If someone is of the mind set its some ones else's issue because you took general suggestions of places to look literally with out the skill to quantify and evaluate when you get in there and create problems... leave it alone as well. Every one will be happier. WHICH is why for the far majority of people, the best place to keep a saw is.....stock, and within the boundaries of a warrantee program as defined by the manufacturer and supported by a good dealer.
I can do 2 strokes, since I work on them from time to time, but I've never used a degree wheel to check port timing. I've read that the carbs on these things are garbage and copies of walbro WT carbs. If I could do a muffler mod and put on a good carb, would that make a difference? I'm going out to block the last 2 cord of firewood out of the stack today, so it'll get another couple of tanks thru it
My humble opinion is do the following. Check the squish. If its more than .040 take the base gasket out and build it with a grey gasket maker like Three Bond 1184, Yamabond, Hondabond. All of which are available from the typical motorsports dealer. Of course measure the thickness of your gasket! Don't want that squish to be too much less than .020; 020 is a good number. A muffler mod if you have the skills. Certainly a "real" carburetor would help. I suspect you would have a noticeable change. Unless the muffler is really plugged up, the gasket delete will make the most difference. A good carb will possibly make things like starting and idling a bit better. Might offer more power too. I'm not as enthusiastic about making loud saws anymore. Thoughtful muffler mods can help power and even reduce operating temperatures theoretically. Some I see from the "elite" are just loud. I also will point out spark arrestor screens need to be retained too...one of the reasons the "dual" port concept is nice where effectively you just add another hole, screen. and shroud.
Weimedog, your two posts are top notch advice lMO for someome tackling the challenge of 2cycle saw tuning! lts an unbelievable thing to be able to sign up to AS, post what would not be a 'popular pro saw' and get help of such credibility without having to pull out the check book. AS is lucky to have members like yourself amoung many others. I say why not get the most out of a china saw! The op could spend many hundred dollars on a popular make and either be to scared to touch it or make a mistake and be up for several more hundred. FWIW my best running ported 50cc class saw blows 185psi and l have others over the 200 mark.
yea I probably coulda bought my friends non running MS280 for a couple hundred, but then been afraid to touch it. It was between the china saw and a Poulan PP20av but didn't want a 20" bar. If I bought the poulan tho I would not have thought about touching it since it would have a warranty... And yea, I really didn't expect to get the great advice I have gotten with this china saw.
You are very welcome, many here posted tips and info I have learned from so certainly encourage you pass along the things you learn as well. I know "Chinese" saws are "taboo" for many here, to me saws are saws. Folks can get all twisted up on who copied what and who sells where. I kind of get a kick out of making sleeper saws from underdogs and have dabbled a bit with Chinese derivatives of Husqvarna 372's and had fun with them... so I'm interested in how your saw turns out and also how long it lasts. SO please keep this thread updated! Preferably with pictures and even better, video...
Having said all that, My advise would have been along the lines of, that Stihl would have put you ahead as it would have resale value and probably could be made to run stronger. Right now the state of the art with the established saw builders is way ahead of the copies and derivatives that are coming out of the Pacific rim. Over time that may change.... I can remember when Maico, CZ, Husqvarna and Bultaco were the Race Bikes to have as well! (Bet most here can't) Don't be taken by surprise when those same suppliers from the Pacific rim up their game.
Having said all that, My advise would have been along the lines of, that Stihl would have put you ahead as it would have resale value and probably could be made to run stronger. Right now the state of the art with the established saw builders is way ahead of the copies and derivatives that are coming out of the Pacific rim. Over time that may change.... I can remember when Maico, CZ, Husqvarna and Bultaco were the Race Bikes to have as well! (Bet most here can't) Don't be taken by surprise when those same suppliers from the Pacific rim up their game.
I'm really only after a firewood saw\ storm cleanup saw. I think if i was dropping down the big bucks on a new saw, it would be a J Red or a husky.
if I can make this thing run half way decent and last a couple years, it will have more than paid for itself. Blocking 3 cord of wood over buying blocked wood for a $20 discount per face its close to paid as is. Minus a cpl gals for the splitter. As to the ms 281. He really didn't want to sell and $200 was his price. It's kinda beat and does not run right.. I am deffinetly keeping this thread active. The fact I got a $120 52cc or 59cc saw and it runs decent out of the box is impressive. My new 34LG chain got dull soon as I hit an old barrel in the ground so no real testing today. It pulled good but dull chain.
if I can make this thing run half way decent and last a couple years, it will have more than paid for itself. Blocking 3 cord of wood over buying blocked wood for a $20 discount per face its close to paid as is. Minus a cpl gals for the splitter. As to the ms 281. He really didn't want to sell and $200 was his price. It's kinda beat and does not run right.. I am deffinetly keeping this thread active. The fact I got a $120 52cc or 59cc saw and it runs decent out of the box is impressive. My new 34LG chain got dull soon as I hit an old barrel in the ground so no real testing today. It pulled good but dull chain.
AS member ChrisPA loves to modd china clones and price range saws even clambshells! Always good threads with surprising results. Don't forget all of these china saws are copies and probably have good room for improvement just getting them closer to what they were copied from. Blueprinting...removing casting floors, adding decent rings, possilbly a real carb ect could really help them. As mentioned pics, vids ect will attract more members input and good luck with your project.
Jimbo209
ArboristSite Guru
I Have 2 like that on my bench in pieces one I got my moneys worth out of and one never run just pulled apart to hack portThis is the only pic i got right now. Hopefully i will tear it apart on day off thursday. Can't do anything since my truck will be borrowed that day.
Jimbo209
ArboristSite Guru
Untill I ran it in palm with loose muffler nuts
It was cheaper than hiring a ms381 for the day by $30/40
I'll post pics of it tomorrow here and start my own aswell
It was cheaper than hiring a ms381 for the day by $30/40
I'll post pics of it tomorrow here and start my own aswell
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