Thinking of trying clean up/porting on cheap chainsaw

[drfeelgood]

So I have getting into chainsaws over the past few years. I have property with a lot of hardwood, and have frequent treefalls from rain, wind, ice and crappy root systems in this Georgia clay. I have muffler modded and tuned all my saws and generally like piddling to try to tweak performance.
Anyhow, thinking of trying some cylinder porting(maybe polish/cleanup to start) on a cheap Chinese saw. Anyone tried this? Watch youtube videos? Will I need any special tools to remove cylinder and replace, like something to compress ring(s), on a 2-stroke. I guess I'm just bored and want to try something new

 

[Zaedock]

So I have getting into chainsaws over the past few years. I have property with a lot of hardwood, and have frequent treefalls from rain, wind, ice and crappy root systems in this Georgia clay. I have muffler modded and tuned all my saws and generally like piddling to try to tweak performance.
Anyhow, thinking of trying some cylinder porting(maybe polish/cleanup to start) on a cheap Chinese saw. Anyone tried this? Watch youtube videos? Will I need any special tools to remove cylinder and replace, like something to compress ring(s), on a 2-stroke. I guess I'm just bored and want to try something new

I compress the ring(s) with my hand and the top end typically slides right on.

I have a few powersaws I've done. Ended up porting my Farmertec 660 clone. It wasn't bad and has actually been reliable. I run an aftermarket muffler as well. Check out Tinman, IronHorse, Westcoast Saw, etc. on Youtube. They have some good videos.

Have fun and wear your chaps.

 

[ripcord]

Paging Dr. @Cujet

 

[oil pan 4]

So I have getting into chainsaws over the past few years. I have property with a lot of hardwood, and have frequent treefalls from rain, wind, ice and crappy root systems in this Georgia clay. I have muffler modded and tuned all my saws and generally like piddling to try to tweak performance.
Anyhow, thinking of trying some cylinder porting(maybe polish/cleanup to start) on a cheap Chinese saw. Anyone tried this? Watch youtube videos? Will I need any special tools to remove cylinder and replace, like something to compress ring(s), on a 2-stroke. I guess I'm just bored and want to try something new

I cut a lot of dead dried hard wood. If my saws had any more power they'd just burn up the bar.
I already keep a trough of used motor oil near by when doing heavy cutting to dip the bar and chain in to cool and clean the bar.

 

[IndyIan]

A chinese copy of a 372xp was pretty cheap, and you might find some information online how to port a 372, or even just match the chinese ports to the swedish saw ones? Also you can buy another chinese jug for a pro saw so you can compare.
There are lots of videos on how to take apart the "good" saws which probably is useful for all saws.

 

[97prizm]

So I have getting into chainsaws over the past few years. I have property with a lot of hardwood, and have frequent treefalls from rain, wind, ice and crappy root systems in this Georgia clay. I have muffler modded and tuned all my saws and generally like piddling to try to tweak performance.
Anyhow, thinking of trying some cylinder porting(maybe polish/cleanup to start) on a cheap Chinese saw. Anyone tried this? Watch youtube videos? Will I need any special tools to remove cylinder and replace, like something to compress ring(s), on a 2-stroke. I guess I'm just bored and want to try something new

Check out the Arborist site forum. One member has a write up on porting and performance.
Chain saw porting

 

[Cujet]

Paging Dr. @Cujet

Haha,

All other things being correct, the biggest porting power gain on a two stroke is getting the exhaust port timing correct. Although with chainsaw engines, there could be other intentional limitations to manage power and emissions, such as small transfer ports.

Since most saws do not run a full tuned expansion chamber exhaust, there are limitations to port size and width for a good outcome.

Yes, absolutely review YouTube porting videos. Depending on what videos you watch, you may actually get good advice. Find someone successful with your model.

There are also some saws with rev limiters built into the coil or ignition system. Preventing you from making a 10,000 RPM saw into a 15,000 RPM ripper. Either stay away from those saws, or buy the parts to make it work correctly.

In the old days on low tune dirt bikes, we'd simply widen the exhaust port to 70% of the bore width and raise it 2mm. On the more modern stuff we'd aim for about 200 degrees of exhaust port timing. But chainsaws generally don't like anywhere near this much exhaust port.

I always preferred a rounded exhaust port roof, to be gentle on the rings. A rectangular exhaust port may give crisp performance but rings can expand into the port and cause problems.

One really neat design I had success with was to widen the exhaust port only at the top, while raising it a bit. Leading to a bread loaf shaped port. This worked really well on 500cc singles. All the timing and flow needed, but easier on the rings.

https://www.arboristsite.com/threads/porting-the-361-big-bore.85488/

Don't neglect to chamfer the port edges to protect the rings.

 

[Zaedock]

I cut a lot of dead dried hard wood. If my saws had any more power they'd just burn up the bar.
I already keep a trough of used motor oil near by when doing heavy cutting to dip the bar and chain in to cool and clean the bar.

You need to adjust your oiler. All I burn/sell is mixed hardwood (Northeast) and my bars never get that hot.

 

[Zaedock]

A chinese copy of a 372xp was pretty cheap, and you might find some information online how to port a 372, or even just match the chinese ports to the swedish saw ones? Also you can buy another chinese jug for a pro saw so you can compare.
There are lots of videos on how to take apart the "good" saws which probably is useful for all saws.

Unfortunately, this is the one Chi-na saw I don't recommend. Nothing but issues with my Holz. In the end, it's better to buy a used real deal in the 372 flavor. I've had better luck with the Stihl copies.

 

[Zaedock]

I just remembered that Tinman did a nice video comparing several aftermarket cylinders. Should be easy enough to find on YouTube.

 

[Zaedock]

@drfeelgood

Looks like a decent price on one of these clones for playing with.

Amazon 372 Clone

 

[bobdoo]

If the cylinder is chrome-plated... Don't.

I had best success on the many cycles I ported, by *slightly* widening the exhaust port, and raising it a bit. (Only raise it if you want more RPM!) Remember to leave a couple millimeters of angle at the top of the port, to guide the bulging rings back into the piston grooves.

I used the kitchen sink to run a large stream of water thru the transfer ports, so I could see what needed to be done.

Do NOT make everything mirror-smooth. Leave a bit of roughness for best flow, and fuel atomization.

If there's a reed valve, you can very carefully port that, too.

You can somewhat widen, and raise the height of the carb, if it doesn't use the throttle *plate*, but uses a plunger.

Match every join between pieces.

 

[Lubener]

So I have getting into chainsaws over the past few years. I have property with a lot of hardwood, and have frequent treefalls from rain, wind, ice and crappy root systems in this Georgia clay. I have muffler modded and tuned all my saws and generally like piddling to try to tweak performance.
Anyhow, thinking of trying some cylinder porting(maybe polish/cleanup to start) on a cheap Chinese saw. Anyone tried this? Watch youtube videos? Will I need any special tools to remove cylinder and replace, like something to compress ring(s), on a 2-stroke. I guess I'm just bored and want to try something new

If the saw works good, leave it alone and find something else to do.

 

[jeepman3071]

The Chinese saws are good to practice porting cylinders on, and once you get a bit better at it I'd find a broken Husqvarna 266 or 272 and port some aftermarket cylinders.

 

[drfeelgood]

If the saw works good, leave it alone and find something else to do.

Well, I guess that is an option!

 

[thetricky]

If the saw works good, leave it alone and find something else to do.

That’s no fun!

I’m jumping on this thread for the simple fact I can’t leave things well enough alone! Watched Tinman’s CS590 porting videos and want to give that a whack. Great info in this thread too!