Differences 45-52-58-(62)cc chinease zenoah clones

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
What really amazes me that by volume, probably half the world (especially the developing countries where cost is the foremost concern) uses ONE same model of chain saw. 7 billion people, millions of engineers and designers, and a huge chunk of the device we call 'chainsaw' was designed by some Japanese dude in the 70s and somewhere in magictown Shenzhen there are a few factories churning out a MAJOR part of the world's chainsaw supply. Just fricken amazing, why reinvent the wheel when the old design works good?
I've thought along similar lines myself. Copying of chainsaw design principles goes way back. Indeed, the Zenoah G5200 itself was unashamedly based on proven Husqvarna and Stihl principles. I understand that some of the copies now available are being made under license from Zenaoh but I suspect that many, if not most, are not.
 
More interest in this topic than I expected.

I first encountered these saws when looking for a second-hand Husqvarna 40 or 45. eBay was full of all kinds of brand names and kooky ads for Chinese-made saws for between AU$70 & $120, all with distinctive Zenoah characteristics.

Initially I considered getting a 45cc example but it was just too heavy so my focus moved to the G3800 copies.
I now have 2 of these. One I bought from the ubiquitous Australian hardware chain "Bunnings", on sale for less than AU$70. It's made under license by Techtronics in China, so it's branded "Homelite" and came with a 12 month replacement warranty. I've been using it occasionally now for a few month, the chain and bar were not great but the powerhead appears to be well made and screwed together.

The other one is branded "Millers Falls" and looks like it was put together by children using whatever leftover screws and AV springs they could find. It works but with serious issues (which I'm happy to detail for anyone who really wants to know). I ended up with this one only because it was just too cheap a source of spares for me to let my friend who bought it on eBay send it back for a refund. He paid AU$57 delivered to his door, including a "Worker" brand 16" bar and chain. I paid him the money, fixed the major problem and sold the unneeded bar and chain for AU$29.
 
There's some miss information on the specs of these saws in this thread.
The 45 and 52cc saws have a 32mm stroke, the 45 is 43mm bore, the 52 is 45mm bore.
Th 58 and 62cc saws have a 34mm stroke, the 58 is 45.2mm bore (its actually a 54.6cc saw) and the 62 is 48mm bore for 61.5cc.
All the cases are the same. I've had them apart for porting and checked the size of them as I was told these don't come in 62cc which is wrong, they do.

I had a 45 which I turned into a 52 and I now have a joncutter 5800 (54.6cc) and a timberpro6150 (61.5cc), they're pretty solid saws and with mods cut pretty fast.

There's a few 62cc ones on ebay, this one is identical to my timberpro.
https://www.ebay.ca/itm/Premium-Per...817826?hash=item5931df76a2:g:gQ4AAOSwOFtdSB0r
 
You need to know what your looking for to get replacement parts for these as the 45-52 parts will fit the 58-62 but you end up with a shorter stroke crank. It does fit so the Chinese sellers advertise it as such.
The 58cc cylinder is taller than the 52cc one, it has better ports but low compression/huge squish if you put it on the 45/52cc saws. This is the most common thing guys buy as they think it will make a 52 or 45 a 58 but it doesn't. The 48mm 62cc cylinder is pretty hard to get so stick with the 58.

In my experience with these saws, the 45 will rev the best if you port it a touch, the 58 or 62 has more torque if you want to cut large wood and the 52 is in the middle. These saws have small carbs and even smaller intakes which choke the bigger ones so they cant rev high.
If you really want the saws to cut get a 372 carb and make an intake so it fits. I added the larger carbs/intakes so my 58 and 62 they rev high and cut fast now. If your going that route bigger is better but with the stock carb/intake the 45 is pretty good and not far behind its bigger brothers.
 
Hi folks,
I'm interested in the differences between the Chinese zenoah g5200 clones in the 45-52-58-62cc range. My understanding was that to upgrade lets say a 52cc saw to a 58cc, one would just have to switch piston and cylinder. In one thread, I read that replacing the crankshaft was also required, perhaps due to port timing, but I am not convinced of that. Replacement cranks are most often marked "fits 45-52-58cc", so I don't really see a difference between a 52cc and 58cc crank, is there one? Does this also apply to 52->62cc conversions (no crank replacement necessary, just top end?). If anyone is the wiser as to explain why a different crank would be needed, I'd like to hear it, as I understand only the cylinder bore width changes, not the stroke? Would be grateful for any ideas!

I have 5 of these saws from 42-56cc, the 42cc is a craftsman made by mtd, a g450avs made by Zenoah, a zenoah g5000, 2 Chinese 52cc versions of the g5200, and a 56cc version of the g5200. They all have the same stoke crankshaft but each cylinder has a different sized bore..... I have some measurements posted here.
https://www.arboristsite.com/community/threads/dissecting-an-earthquake-chainsaw.214984/page-157
45, 52 & 58 models all have outboard clutches. (Maybe that's what 'Dph 1256' actually meant.)

Thank you for clearing that up I was under the impression that the 45 52 and 58 had inboard clutches.

Someone said that the 62cc model was based on the Zenoah g621.[/QUOTE]

G5200 based "62"cc
images

G621 based 62cc with an inboard clutch
G621-62CC-Gasoline-chainsaw.jpg_300x300.jpg


These two are completely different designs and no parts interchange. I have a real g621 too.
 
There's some miss information on the specs of these saws in this thread.
The 45 and 52cc saws have a 32mm stroke, the 45 is 43mm bore, the 52 is 45mm bore.
Th 58 and 62cc saws have a 34mm stroke, the 58 is 45.2mm bore (its actually a 54.6cc saw) and the 62 is 48mm bore for 61.5cc.
All the cases are the same. I've had them apart for porting and checked the size of them as I was told these don't come in 62cc which is wrong, they do.

I had a 45 which I turned into a 52 and I now have a joncutter 5800 (54.6cc) and a timberpro6150 (61.5cc), they're pretty solid saws and with mods cut pretty fast.

There's a few 62cc ones on ebay, this one is identical to my timberpro.
https://www.ebay.ca/itm/Premium-Per...817826?hash=item5931df76a2:g:gQ4AAOSwOFtdSB0r
That’s good info thanks for joining the party :)

So the 52 is actually 50cc if u do the calculations
 
I have 5 of these saws from 42-56cc.....

G5200 based "62"cc
images

G621 based 62cc with an inboard clutch
G621-62CC-Gasoline-chainsaw.jpg_300x300.jpg
I was wondering if/when you might turn up here. Happy to have my observation and conjecture confirmed or denied by those who've seen more than photos and IPLs.

Now, of course, I suppose I'll have to read through the Earthquake thread too!:D
 
Hi
There's some miss information on the specs of these saws in this thread.
The 45 and 52cc saws have a 32mm stroke, the 45 is 43mm bore, the 52 is 45mm bore.
Th 58 and 62cc saws have a 34mm stroke, the 58 is 45.2mm bore (its actually a 54.6cc saw) and the 62 is 48mm bore for 61.5cc.
All the cases are the same. I've had them apart for porting and checked the size of them as I was told these don't come in 62cc which is wrong, they do.
Hmm. So it's the 58cc claim that's suspect and the 62cc is justified.

My reasons for doubting the longer stroke were engineering based. Simply increasing the crankpin offset by 1mm without enlarging the crankcase internally would mean reducing the diameter of the big-end bearing and/or the outside diameter of the conrod big-end, meaning you wouldn't gain much, if any, advantage from the extra capacity....except of course, the marketing pull.:nofunny:
 
The rod maybe different but it doesn't matter, the size of the rod has no effect on power, the longer stroke makes more torque which is nice when the saw is still the same size/weight to run.

I'd like to try one of the 62cc saws with the inboard clutch, they have bigger carbs/intakes/ports so they should be stronger. I've never seen one come up on ebay tho. It's easy to spot the difference between them looking at the chain brake, single post on the outboard clutch, double on the inboard clutch.
 
The rod maybe different but it doesn't matter, the size of the rod has no effect on power, the longer stroke makes more torque which is nice when the saw is still the same size/weight to run.
It's about durability not power. We're talking about an engine with low specific output and a product clearly aimed at the bottom of the market so I understand the compromise chosen in this case.
Different though if making a 62cc version of an existing 54cc engine that priduces 4hp at 10,000rpm and max torque at 7,000. Then (I hope) they'd be less comfortable skimping on the big-end and increasing the angle of rotation of the little-end around the gudgeon pin.

So I agree with you, the 62cc copy with the inboard clutch and larger inlet should indeed be stronger, in every sense.
 
There's lots of the 62cc ones (timberpro6150, baus62, mtm62sx, yz6200, etc) around on youtube, yes it is a 50 punched out to a 60 but issues are rare.

Im more apt to have crank issues than anyone as I modded mine and run it at 14000-14400rpm max revs and it cuts at 12000rpm. Stock these max rev 12000rpm and cut at 9000rpm. I haven't blown mine up yet so I wouldn't worry about it too much.
The smaller joncutter 5800 likes to be set at 15000rpm when modded, we'll see how long that cheap china crank last lol.
 
Thanks for all the great info guys! NSEric, seeing you have had these parts in your hands and measured them, so you say not only is the cylinder/piston larger, but also that the crankshaft has other dimensions and geometry (albeit only 1mm of resulting offset all in all). Does the crankshaft have a different OD compared to the 45/52cc one, requiring different bearings, or does the OD remain the same at the bearings, and the old ones can be reused?
 
While I never got one of the G5000 - based Zenoah clones, I noticed that there are a couple of different outfits making cylinders, and different transfer configurations. I believe the original Zenoah engines were dual closed transfers. The clones will be open transfers, but some of them will be quads, which is what you’d want. Of course there’s no way to tell on a built saw.

My mildly modded G621 clone still runs strong and is dead solid reliable. As is my heavily modified Earthquake G3800 clone.

https://www.arboristsite.com/community/threads/porting-a-chinese-g621-clone.253359/
 
Does the crankshaft have a different OD compared to the 45/52cc one, requiring different bearings, or does the OD remain the same at the bearings, and the old ones can be reused?
My assumption has been that it couldn't have larger counterweights because that dimension it's confined within the same crankcase and that the bearings are the same standard size too so I'll be interested in the answer.
 
I just read your G621 copy experience. You certainly found out what you're not paying for.:D
Makes my "Millers Falls" junk pile 3800 copy seem well built in comparison! https://www.arboristsite.com/commun...ease-zenoah-clones.334500/page-2#post-6969802
Yes, but now it is a light, strong and reliable saw. What it lacked was proper assembly, attention to casting clean up, etc. In fairness the plastic parts were prepped no worse than my dad’s MS250 (which is to say not at all).

Those are the kinds of things any manufacturer can do, it just costs a bit more in labor - which you don’t get on a no-name bottom dollar clone. The saws are based on good Zenoah designs and the Chinese graduate more manufacturing engineers than anyone else. They can be assembled with whatever level of quality the importer/exporter is willing to pay for.

Or you can go cheap and do it yourself.
 
Just for completeness, I found a VIDEO of a guy doing a 5200->5800 upgrade, which includes the crank. Not sure if he was rebuilding a 'bad' saw, since it looks quite new, but bearings were also replaced, I would believe unnecessarily. Unfortunately it is in Romanian, but still gives a good overview of what parts need to be replaced. Thanks for all the great input guys!

Just as an aside, I believe same applies to the typical brush cutters in their standard chinese form, the ones with the bottom facing priming bulb, and twist barrel carb (Walbro WYK 196 clone I believe) in their 25-35-48-52cc guises, all being just cylinder/jug swaps. If anyone has a comment regarding these, would be an interesting comparison.
As many have stated, it seems that the displacement increases don't translate at least linearly to improvements in power. Would you consider them more of a marketing gimmick, or just diminishing returns? Is the consensus that carb sizing is mostly to blame, being the primary bottleneck maybe after transfer port geometry? Anyone with a bit of carb engineering experience, how does one size a carb to a small engine, surely some calculation is involved, but is there a more general rule? Is there a chart somewhere that nicely lets one compare Walbro carbs as to their venturi diameters and perhaps mounting arrangement, that would ease any consideration of replacing a more fitting carb.
 
I never seen the brush cutters but on the chainsaws the intake is just as small as the carb. To mount a bigger carb you need a bigger intake too. Im guessing whoever bored and stroked these 50cc saws into 60cc saws wasn't too concerned with power out put as long as it was a little better than the 50. I doubt it cost a cent more to make them 58 or 62cc compared to 45 or 52cc, if you were to redo the intake and carb so the 58 or 62 runs its best it would cost a bunch more. The transfers are holding them back too, the 54.6cc "58" is dam near as strong as the 62 because of the small transfers IMO.

I copied someone elses carb/intake setup, while I have 2 saws with it I cant take credit for making them fit. The 365/372 carb has the same bolt pattern and impluse line setup, everything else is close enough a few tweaks makes it fit. This carb is a touch bigger than need be but nothing a little smaller bolts on. The intake is only a 1/2 inch in the smallest part stock, the new one is 3/4 or 7/8. The new intake has to be shorter so the longer carb will fit.

I added the bigger carb/intake to my 58 with no other mods at all, it went from cutting at 9000rpm to 11500rpm, that's a huge gain. I have since ported it too but the carb/intake is responsible for 80-90% of the gains. I wish I had a do over on my 62 so I could try the carb/intake swap on it before porting it, I ported it first. It only gained a little bit ported then gained a bunch when I put the carb/intake on it.
 
Back
Top