JonCutter thread...

[afleetcommand]

So this can be the JonCutter discussion, taking it off the 372 thread... LOOKS like there can be a lot of fun with these goofy things.

 

[Leafy]

Same as the earthquake saws guys were getting "refurbished" for $50 a few years ago, and same as the recent craftsman, blue max, and remington saws except those must have catalyst mufflers. Also the same as some timberpros. They're g450 clones punched out. There's similar looking ones with internal clutches at 62cc that's a copy of a different zenoah but they're harder to find.

52cc is the most common configuration, easy to find for under $100, start every time great for limbing because they're so light. They do come with like a 19.5" bar that uses a weird length chain that's total trash from the factory but one guy on at sells lgx loops made to that off a roll. They take small husky mount bars and then will use a normal length chain.

If you're going to modify them, get comfortable with aliexpress. Top end kits are only $20, you want the quad port that matches your displacement you can tell a quad port from the small fins on the top. Dual port mufflers have the most flow without being modded, single port is the best to mod because the port is larger and better matches 3/4" od tubing. 372 carbs fit good, you just need to drill a hole in the throttle lever for the throttle bar to connect, doesn't result in much gain though without going to a larger diameter intake tube, I'm on revision 3 of my 3d printed one and not happy enough to sell it.

 

[P.M.P.]

That 5800 Looks like a copy of the redmax g5000 I got. Wonder if the clutch cover would work. Not that I need one right now but maybe down the road.

 

[Spike60]

This could be a hoot. Cheap prices, all kinds of crazy colors and apparently some decent running saws.

Could that 62cc saw be a copy of the Red Max 621? That was a pretty good saw, that hardly anyone knows about.

 

[Leafy]

Yeah 62cc is a 621 copy some guy on arboristsite has a thread on it. They're hard to find. You'll see a few on ebay listed as 62cc but they're 52cc, that's how I got mine for free, it came external clutch I measured the bore and stroke, complained and got refunded.

 

[Czed]

That 5800 Looks like a copy of the redmax g5000 I got. Wonder if the clutch cover would work. Not that I need one right now but maybe down the road.

Here ya go
https://m.aliexpress.com/wholesale/...ulocawst16c586305b528b1505e5fd494e&gclid=null

 

[Leafy]

Oh and if you get a new clutch cover, you can order the side screw tension adjuster so you need to get the screw driver right against the bar. I think the adjuster kit is like $8.

 

[NSEric]

I like my joncutter. Since I have a bunch of .325 chains/bars I swapped to a 8 pin .325 rim.
I added the 372 carb, a home made intake similar to the one leafy sold me(its on my timberpro 6150) and did a little porting.
Im a hack when it comes to porting so I don't go too far, its easy to make them slower without a degree wheel.
Here's a vid, I have it turned up to 15000rpm, I tried it a little lower too but that's where its fastest.

 

[P.M.P.]

I like my joncutter. Since I have a bunch of .325 chains/bars I swapped to a 8 pin .325 rim.
I added the 372 carb, a home made intake similar to the one leafy sold me(its on my timberpro 6150) and did a little porting.
Im a hack when it comes to porting so I don't go too far, its easy to make them slower without a degree wheel.
Here's a vid, I have it turned up to 15000rpm, I tried it a little lower too but that's where its fastest.

Nice job Eric get yourself a degree wheel you will be glad you did.
That 5800 impressive

 

[NSEric]

I'v had the 62cc version. Is 48bore x34 stroke. The cylinder extension is a lil bigger than all the others cylinders. So the case is wider. The crank fits all the other cases( 45cc .52cc.58cc= the same). My favorite combo: 34 stroke crank and dual open transfer cylinder.

I copied this from the other chinese chainsaw thread as to not clutter it up with joncutter stuff.

My plan for the 58 joncutter before I even bought it was to put the shorter dual open transfer 52cc jug on the longer stroke 58 saw to gain compression, the ports are pretty much the same so it should run good.
It sounds like this guy did the same thing, has anyone else tried this swap?
Once I ran the saw and checked the compression I changed my mind, it ran good stock and had 175psi stock so it didn't need more compression and I never did the swap.

The 45cc one I had was 200psi with no base gasket, it ran as good as the 52 I turned it into when it had a stock carb. If sticking with stock carbs/intakes I recommend the 4500 joncutter, it will run good ported.
I have every cylinder they make for these saws, 43mm and 45mm dual transfer, 45.2mm quad transfer, (2 counting the one on the joncutter) the other was ported and run on my 52, I copied what I did to the timberpro grinding out the divider in the transfers tho, this didn't work good on the 32mm stroke 52cc saw, the squish was .075 and the compression was too low (120psi). I didn't run it before porting it tho so I don't know if it was a slug because I ported it wrong or from the huge squish.
The timberpro is 48mm quad transfer, when I ported it I totally ground out the dividers making it dual transfer, it gained a bit doing it too but at 61.5cc it needs bigger transfers. It looks like this cylinder would bolt right on the smaller saws but I'd have to measure it to be sure and honestly the 5800 is dam near as strong so its not really worth the cost/effort.

 

[afleetcommand]

I'v had the 62cc version. Is 48bore x34 stroke. The cylinder extension is a lil bigger than all the others cylinders. So the case is wider. The crank fits all the other cases( 45cc .52cc.58cc= the same). My favorite combo: 34 stroke crank and dual open transfer cylinder.

I copied this from the other chinese chainsaw thread as to not clutter it up with joncutter stuff.

My plan for the 58 joncutter before I even bought it was to put the shorter dual open transfer 52cc jug on the longer stroke 58 saw to gain compression, the ports are pretty much the same so it should run good.
It sounds like this guy did the same thing, has anyone else tried this swap?
Once I ran the saw and checked the compression I changed my mind, it ran good stock and had 175psi stock so it didn't need more compression and I never did the swap.

The 45cc one I had was 200psi with no base gasket, it ran as good as the 52 I turned it into when it had a stock carb. If sticking with stock carbs/intakes I recommend the 4500 joncutter, it will run good ported.
I have every cylinder they make for these saws, 43mm and 45mm dual transfer, 45.2mm quad transfer, (2 counting the one on the joncutter) the other was ported and run on my 52, I copied what I did to the timberpro grinding out the divider in the transfers tho, this didn't work good on the 32mm stroke 52cc saw, the squish was .075 and the compression was too low (120psi). I didn't run it before porting it tho so I don't know if it was a slug because I ported it wrong or from the huge squish.
The timberpro is 48mm quad transfer, when I ported it I totally ground out the dividers making it dual transfer, it gained a bit doing it too but at 61.5cc it needs bigger transfers. It looks like this cylinder would bolt right on the smaller saws but I'd have to measure it to be sure and honestly the 5800 is dam near as strong so its not really worth the cost/effort.

Good to see folks using basics to improve these little saws....fun without turning it into a religious experience. I for one have gotten to a point I rather spend more time making wood chips than metal ones with a saw. And being able to get significant changes with simple changes gets both itches scratched...and with a saw "plateform" such as this one the price point makes the risk low as well. Bang per buck....

 

[Leafy]

And here we can see how much the tolerances vary between these saws. I think the quad ports are way better. My first build was 52cc with the stock jug, I destroyed the base gasket taking it apart and didn't measure squish before, I threw it back together with no base gasket and it was a head slapper. That one caught a ring on the exhaust port and I threw a 58cc quad port jug on it unported, I couldn't fold the solder over enough to get a squish measurement it was so open, ran 2k less rpm than the original build but cut just at well. Now I have a ported 52cc quad port that has 24 thou of squish with a base gasket and I radiused the exhaust port and matched the radius on the piston, I also trimmed the piston skirt to match the profile of the bottom of the intake, I had to move the transfers 6 freaking mm, on the dual transfer saw I got away with just filling a couple mm off the piston to get the blow down decent. Anyway I haven't run this new top end in wood yet because I can seem to fuel it, just super lean in the mid range, one it gets to high rpm it's running 14kish. I'm going to leak test it before I go try and mod the clone zama.

 

[David Young]

I bought a 45cc one. It looks a lot like a g5000 but is open port. Mine has 190 psi only thing I have done is tuned the carb. It sounds decent and runs not to bad for 100 shipped. I am frankly impressed with it overall. I bought a larger cylinder but haven’t messed with it yet. Thanks for sharing all the info guys.

 

[NSEric]

Anyway I haven't run this new top end in wood yet because I can seem to fuel it, just super lean in the mid range, one it gets to high rpm it's running 14kish. I'm going to leak test it before I go try and mod the clone zama.

My 45cc saw was like that with 3 different carbs, 2 different intakes and 3 different cylinders, so I gave up on it and bought the joncutter.
It had other issues so I didn't want to put new crank seals in it, the tank vent port into the tank was messed up and the gas cap sucked you had to remove it with a wrench. This saw was given to me as it didn't run right, it's at least 10 years old, it looks just like the joncutter so its a good parts saw.

I was just out cutting with both my saws, the bigger timberpro has a bit more power than the joncutter, the timberpro wasn't sharp in my last videos, it has enough balls I don't notice right away when its dull. IDK if its the extra cc's or the bigger transfers you get with the dividers ground out of em but its more powerful and the exact same size/weight. I don't need to do anything to my saws now, I just need to get better sharpening chains, my poor sharpening is holding my saws back more than anything.

If you can find one that's 61.5cc 48mm bore by 34mm stroke I'd get it, bigger is better lol.

 

[NSEric]

I had the top off the timberpro to fix the kill switch so I checked the bolt pattern of the cylinder, its the same as the smaller saws so you can put the 48mm top end on if you want to. The fins are bigger but everything else is the same size.

I took a few pics of my ported 45cc cylinder and piston. This set up was as strong as the stock bigger saws. If someone wanted to port a joncutter4500 this works.
I took a little under 1/16 off the top of the exhaust port, top of piston by the transfers, intake skirt of the piston, I also took some off the bottom of the piston beside the transfers and the corner of the transfers on the bottom of the cylinder. I widened the exhaust by about 1/4 of an inch on both sides and took 1/16 off every side of the exhaust flange, gasket and inlet on the muffler. I never touched the intake port. I ran mine with no base gasket but some are head slappers so check your squish.

 

[NSEric]

I took a pic of what I did to the transfers on the 61.5cc saw, im tempted to do this to the joncutter but its running really good.
I completely removed the dividers in the transfers on that saw and it rips. This pic is my spare 45.2mm cylinder, I didn't take the saw apart to take a pic lol.

When I ported the joncutter I only removed about a 1/2 inch of the divider and knife edged it to help flow into the transfers. This is a small improvement that doesn't hurt the saw for sure. Im not sure if completely removing the dividers will help the smaller joncutter.

 

[NSEric]

This is what I did to the transfers in the joncutter5800.
The pic is from the first round of porting the 61.5 but I did the exact same thing.

 

[Spike60]

Geez, you guys are teaching a graduate course on these saws. Great info!

Some of us got some catching up to do.

 

[p61 western]

Geez, you guys are teaching a graduate course on these saws. Great info!

Some of us got some catching up to do.

And need to get one lol. It's pretty tempting for me to buy one.

 

[Spike60]

I hardly need one of these things either, but they are too cheap to ignore and this looks like it will be fun.

The saws in Eric's video are running pretty sweet.